Knowledge of the oceans is more than a matter of curiosity

Our very survival may hinge upon itldquo

- John F Kennedy -

Quick Plankton Guide

ChaetocerosConscinodiscus Chaetoceros Ditylum

Cylindrotheca Stephanopyxis ThalassionemaNavicula

dinoflagellate Protoperidinium

dinoflagellate Ceratium

dinoflagellate CeratiumLicmorpha

ciliates radiolarian foramniferan jelly medusa

jelly medusa ctenophore ctenophore Oweniidae larva

Quick Plankton Guide

polychaete larvae arrow worm snail veliger pteropod

bivalve veliger cladoceran copepod nauplius copepod

cumacean krill barnacle nauplius barnacle cyprid

shrimp crab zoea crab megalop urchin larva

sea star larva tunicate larva fish egg fish larva

Diatoms Kingdom Protista

Phylum Bacillariophyta

5-60 microm

chains can be longer

Taxonomy Size

Diatoms are single-celled algae usuallygolden-brown or yellow-green Diatoms typicallydominate the phytoplankton community intemperate regions They are importantproducers forming the base of ocean foodchains Diatoms are probably the single mostimportant food source in the ocean

Energy sourceSun - Diatoms are photosynthesizers

Predators Zooplankton

Life spanA few days to a few weeks

Viewing tipsTo see phytoplankton well you typically need100X magnification or greater It is easy to floodplankton with too much light so reduce lightand illuminate the slide from below

Interesting factsDiatoms produce oxygen through the process of

photosynthesis and along with the other phytoplankton are responsible for 50-85 of theEarthrsquos oxygen

Diatoms use oil and many spines to help stay afloat in the ocean Some also form chains toincrease their ability to float Floating near the surface is important because diatoms needthe sun to produce energy and the sunlight only penetrates to approx 600 ft

The shape of a diatom is often what is used to identify it There are three major shapes

Disc-likecentric diatoms (shell radiates from a central point) Rod-like

Boat-shapedpennate diatoms

There are thousands of different phytoplankton Using the pictures on the next few pagesyou can identify some of these diatoms by their shape We have featured the most common diatoms seen in Kachemak Bay Remember that some diatom species can ldquochainuprdquo and create different shapes

Diatom - disc-like or centric SizeConscinodiscus spp top view

200-300 microm

side view

Diatom - disc-like - Chaetoceros spp Size

100-500 microm

This genus is one of the largest of marine plankton with 400 species described

Diatom - triangular Size Ditylum 250 microm

SizeDiatom - cylindrical chain 100 micromStephanopyxis

Diatom - rod-like chain Size Thalassionema 300-400 microm

Diatom - rod-like Size

Cylindrotheca 100-1000 microm

Diatom - rod-like Size Size

100 microm Psedo-nitzschiaBacillaria 100 microm

Diatom - boat-like or pennate

Protoperidinium sp

Dinoflagellates Kingdom Protista

Phylum Dinoflagellata 100-2000 microm

Taxonomy Size

Dinoflagellates are complex one-celled algaein the Protista kingdom

Energy sourceDinoflagellates are odd members of thephytoplankton community While typicallyconsidered plant-like due to their capacity tophotosynthesize they can swim using twotiny whip-like flagella like simple animalsSome even eat other organisms which mostplants are not capable of

Predators Small crustaceans fish larvae and other protists

Interesting factsSome dinoflagellates are bioluminescentcreating light when disturbed by waves boatwakes or predators

Toxic red tides are sometimes caused bymembers of this group The genus that isharmful here in Kachemak Bay isAlexandrium When large blooms of thesedinoflagellates occur fish and filter-feedinginvertebrates like clams become contaminated

The cell wall of some dinoflagellates arearmored with plates composed of cellulose

Dinoflagellate Size Ceratium spp 100 microm

Dinoflagellate SizeCeratium spp 100 microm

Phylum Arthropoda Subphylum Class Crustacea Subclass Copepoda ndash Subclass Ostracoda ndash

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Porifera ndash sponges

Phylum Cnidaria Class Hydrozoa ndash hydroids hydromedusae Class Scyphozoa ndash true jellyfish Class Anthozoa ndash sea anemones corals sea pens

Phylum Ctenophora ndash comb jellies

Phylum Platyhelminthes ndash flatworms

Phylum Nemertea ndash ribbon worms

Phylum Annelida Class Polychaete ndash polychaete worms

Phylum Sipuncula ndash peanut worms

Phylum Echiura ndash fat innkeeper

Phylum Mollusca Class Polyplacophora ndash chitons

Class Gastropoda Subclass Prosobranchia - snails

Subclass Heterobranchia Superorder Opisthobranchia ndash nudibranchs

Class Bivalvia ndash clams mussels scallops Class Cephalopoda ndash octopuses squids

copepods ostracods

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Arthropoda (continued) Subclass Malacostraca

Order Mysidacea ndash mysid shrimp Order Hemicaridea ndash cumaceans

Order Edriophthalma Suborder Isopoda ndash isopods

Suborder Amphipoda ndash amphipods Order Euphausiacea ndash krill

Order Decapoda Suborder Dendrobranchiata ndash large shrimps prawns Suborder Eukyphida ndash small shrimps Suborder Reptantia ndash crabs (+ lobsters crayfish) Class Maxillopoda Subclass Thecostraca

Order Cirripedia ndash barnacles

Phylum Brachiopoda ndash brachiopods lamp shells

Phylum Ectoprocta (Bryozoa) ndash bryozoans

Phylum Echinodermata Class Asteroidea ndash sea stars

Class Ophiuroidea ndash brittle stars Class Echinoidea ndash sea urchins Class Holothuroidea ndash sea cucumbers

Phylum Chordata Subphylum Urochordata ndash tunicates

Class Ascidiacea ndash sea squirts Class Thaliacea ndash salps

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Quick Plankton Guide

ChaetocerosConscinodiscus Chaetoceros Ditylum

Cylindrotheca Stephanopyxis ThalassionemaNavicula

dinoflagellate Protoperidinium

dinoflagellate Ceratium

dinoflagellate CeratiumLicmorpha

ciliates radiolarian foramniferan jelly medusa

jelly medusa ctenophore ctenophore Oweniidae larva

Quick Plankton Guide

polychaete larvae arrow worm snail veliger pteropod

bivalve veliger cladoceran copepod nauplius copepod

cumacean krill barnacle nauplius barnacle cyprid

shrimp crab zoea crab megalop urchin larva

sea star larva tunicate larva fish egg fish larva

Diatoms Kingdom Protista

Phylum Bacillariophyta

5-60 microm

chains can be longer

Taxonomy Size

Diatoms are single-celled algae usuallygolden-brown or yellow-green Diatoms typicallydominate the phytoplankton community intemperate regions They are importantproducers forming the base of ocean foodchains Diatoms are probably the single mostimportant food source in the ocean

Energy sourceSun - Diatoms are photosynthesizers

Predators Zooplankton

Life spanA few days to a few weeks

Viewing tipsTo see phytoplankton well you typically need100X magnification or greater It is easy to floodplankton with too much light so reduce lightand illuminate the slide from below

Interesting factsDiatoms produce oxygen through the process of

photosynthesis and along with the other phytoplankton are responsible for 50-85 of theEarthrsquos oxygen

Diatoms use oil and many spines to help stay afloat in the ocean Some also form chains toincrease their ability to float Floating near the surface is important because diatoms needthe sun to produce energy and the sunlight only penetrates to approx 600 ft

The shape of a diatom is often what is used to identify it There are three major shapes

Disc-likecentric diatoms (shell radiates from a central point) Rod-like

Boat-shapedpennate diatoms

There are thousands of different phytoplankton Using the pictures on the next few pagesyou can identify some of these diatoms by their shape We have featured the most common diatoms seen in Kachemak Bay Remember that some diatom species can ldquochainuprdquo and create different shapes

Diatom - disc-like or centric SizeConscinodiscus spp top view

200-300 microm

side view

Diatom - disc-like - Chaetoceros spp Size

100-500 microm

This genus is one of the largest of marine plankton with 400 species described

Diatom - triangular Size Ditylum 250 microm

SizeDiatom - cylindrical chain 100 micromStephanopyxis

Diatom - rod-like chain Size Thalassionema 300-400 microm

Diatom - rod-like Size

Cylindrotheca 100-1000 microm

Diatom - rod-like Size Size

100 microm Psedo-nitzschiaBacillaria 100 microm

Diatom - boat-like or pennate

Protoperidinium sp

Dinoflagellates Kingdom Protista

Phylum Dinoflagellata 100-2000 microm

Taxonomy Size

Dinoflagellates are complex one-celled algaein the Protista kingdom

Energy sourceDinoflagellates are odd members of thephytoplankton community While typicallyconsidered plant-like due to their capacity tophotosynthesize they can swim using twotiny whip-like flagella like simple animalsSome even eat other organisms which mostplants are not capable of

Predators Small crustaceans fish larvae and other protists

Interesting factsSome dinoflagellates are bioluminescentcreating light when disturbed by waves boatwakes or predators

Toxic red tides are sometimes caused bymembers of this group The genus that isharmful here in Kachemak Bay isAlexandrium When large blooms of thesedinoflagellates occur fish and filter-feedinginvertebrates like clams become contaminated

The cell wall of some dinoflagellates arearmored with plates composed of cellulose

Dinoflagellate Size Ceratium spp 100 microm

Dinoflagellate SizeCeratium spp 100 microm

Phylum Arthropoda Subphylum Class Crustacea Subclass Copepoda ndash Subclass Ostracoda ndash

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Porifera ndash sponges

Phylum Cnidaria Class Hydrozoa ndash hydroids hydromedusae Class Scyphozoa ndash true jellyfish Class Anthozoa ndash sea anemones corals sea pens

Phylum Ctenophora ndash comb jellies

Phylum Platyhelminthes ndash flatworms

Phylum Nemertea ndash ribbon worms

Phylum Annelida Class Polychaete ndash polychaete worms

Phylum Sipuncula ndash peanut worms

Phylum Echiura ndash fat innkeeper

Phylum Mollusca Class Polyplacophora ndash chitons

Class Gastropoda Subclass Prosobranchia - snails

Subclass Heterobranchia Superorder Opisthobranchia ndash nudibranchs

Class Bivalvia ndash clams mussels scallops Class Cephalopoda ndash octopuses squids

copepods ostracods

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Arthropoda (continued) Subclass Malacostraca

Order Mysidacea ndash mysid shrimp Order Hemicaridea ndash cumaceans

Order Edriophthalma Suborder Isopoda ndash isopods

Suborder Amphipoda ndash amphipods Order Euphausiacea ndash krill

Order Decapoda Suborder Dendrobranchiata ndash large shrimps prawns Suborder Eukyphida ndash small shrimps Suborder Reptantia ndash crabs (+ lobsters crayfish) Class Maxillopoda Subclass Thecostraca

Order Cirripedia ndash barnacles

Phylum Brachiopoda ndash brachiopods lamp shells

Phylum Ectoprocta (Bryozoa) ndash bryozoans

Phylum Echinodermata Class Asteroidea ndash sea stars

Class Ophiuroidea ndash brittle stars Class Echinoidea ndash sea urchins Class Holothuroidea ndash sea cucumbers

Phylum Chordata Subphylum Urochordata ndash tunicates

Class Ascidiacea ndash sea squirts Class Thaliacea ndash salps

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Quick Plankton Guide

polychaete larvae arrow worm snail veliger pteropod

bivalve veliger cladoceran copepod nauplius copepod

cumacean krill barnacle nauplius barnacle cyprid

shrimp crab zoea crab megalop urchin larva

sea star larva tunicate larva fish egg fish larva

Diatoms Kingdom Protista

Phylum Bacillariophyta

5-60 microm

chains can be longer

Taxonomy Size

Diatoms are single-celled algae usuallygolden-brown or yellow-green Diatoms typicallydominate the phytoplankton community intemperate regions They are importantproducers forming the base of ocean foodchains Diatoms are probably the single mostimportant food source in the ocean

Energy sourceSun - Diatoms are photosynthesizers

Predators Zooplankton

Life spanA few days to a few weeks

Viewing tipsTo see phytoplankton well you typically need100X magnification or greater It is easy to floodplankton with too much light so reduce lightand illuminate the slide from below

Interesting factsDiatoms produce oxygen through the process of

photosynthesis and along with the other phytoplankton are responsible for 50-85 of theEarthrsquos oxygen

Diatoms use oil and many spines to help stay afloat in the ocean Some also form chains toincrease their ability to float Floating near the surface is important because diatoms needthe sun to produce energy and the sunlight only penetrates to approx 600 ft

The shape of a diatom is often what is used to identify it There are three major shapes

Disc-likecentric diatoms (shell radiates from a central point) Rod-like

Boat-shapedpennate diatoms

There are thousands of different phytoplankton Using the pictures on the next few pagesyou can identify some of these diatoms by their shape We have featured the most common diatoms seen in Kachemak Bay Remember that some diatom species can ldquochainuprdquo and create different shapes

Diatom - disc-like or centric SizeConscinodiscus spp top view

200-300 microm

side view

Diatom - disc-like - Chaetoceros spp Size

100-500 microm

This genus is one of the largest of marine plankton with 400 species described

Diatom - triangular Size Ditylum 250 microm

SizeDiatom - cylindrical chain 100 micromStephanopyxis

Diatom - rod-like chain Size Thalassionema 300-400 microm

Diatom - rod-like Size

Cylindrotheca 100-1000 microm

Diatom - rod-like Size Size

100 microm Psedo-nitzschiaBacillaria 100 microm

Diatom - boat-like or pennate

Protoperidinium sp

Dinoflagellates Kingdom Protista

Phylum Dinoflagellata 100-2000 microm

Taxonomy Size

Dinoflagellates are complex one-celled algaein the Protista kingdom

Energy sourceDinoflagellates are odd members of thephytoplankton community While typicallyconsidered plant-like due to their capacity tophotosynthesize they can swim using twotiny whip-like flagella like simple animalsSome even eat other organisms which mostplants are not capable of

Predators Small crustaceans fish larvae and other protists

Interesting factsSome dinoflagellates are bioluminescentcreating light when disturbed by waves boatwakes or predators

Toxic red tides are sometimes caused bymembers of this group The genus that isharmful here in Kachemak Bay isAlexandrium When large blooms of thesedinoflagellates occur fish and filter-feedinginvertebrates like clams become contaminated

The cell wall of some dinoflagellates arearmored with plates composed of cellulose

Dinoflagellate Size Ceratium spp 100 microm

Dinoflagellate SizeCeratium spp 100 microm

Phylum Arthropoda Subphylum Class Crustacea Subclass Copepoda ndash Subclass Ostracoda ndash

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Porifera ndash sponges

Phylum Cnidaria Class Hydrozoa ndash hydroids hydromedusae Class Scyphozoa ndash true jellyfish Class Anthozoa ndash sea anemones corals sea pens

Phylum Ctenophora ndash comb jellies

Phylum Platyhelminthes ndash flatworms

Phylum Nemertea ndash ribbon worms

Phylum Annelida Class Polychaete ndash polychaete worms

Phylum Sipuncula ndash peanut worms

Phylum Echiura ndash fat innkeeper

Phylum Mollusca Class Polyplacophora ndash chitons

Class Gastropoda Subclass Prosobranchia - snails

Subclass Heterobranchia Superorder Opisthobranchia ndash nudibranchs

Class Bivalvia ndash clams mussels scallops Class Cephalopoda ndash octopuses squids

copepods ostracods

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Arthropoda (continued) Subclass Malacostraca

Order Mysidacea ndash mysid shrimp Order Hemicaridea ndash cumaceans

Order Edriophthalma Suborder Isopoda ndash isopods

Suborder Amphipoda ndash amphipods Order Euphausiacea ndash krill

Order Decapoda Suborder Dendrobranchiata ndash large shrimps prawns Suborder Eukyphida ndash small shrimps Suborder Reptantia ndash crabs (+ lobsters crayfish) Class Maxillopoda Subclass Thecostraca

Order Cirripedia ndash barnacles

Phylum Brachiopoda ndash brachiopods lamp shells

Phylum Ectoprocta (Bryozoa) ndash bryozoans

Phylum Echinodermata Class Asteroidea ndash sea stars

Class Ophiuroidea ndash brittle stars Class Echinoidea ndash sea urchins Class Holothuroidea ndash sea cucumbers

Phylum Chordata Subphylum Urochordata ndash tunicates

Class Ascidiacea ndash sea squirts Class Thaliacea ndash salps

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Diatoms Kingdom Protista

Phylum Bacillariophyta

5-60 microm

chains can be longer

Taxonomy Size

Diatoms are single-celled algae usuallygolden-brown or yellow-green Diatoms typicallydominate the phytoplankton community intemperate regions They are importantproducers forming the base of ocean foodchains Diatoms are probably the single mostimportant food source in the ocean

Energy sourceSun - Diatoms are photosynthesizers

Predators Zooplankton

Life spanA few days to a few weeks

Viewing tipsTo see phytoplankton well you typically need100X magnification or greater It is easy to floodplankton with too much light so reduce lightand illuminate the slide from below

Interesting factsDiatoms produce oxygen through the process of

photosynthesis and along with the other phytoplankton are responsible for 50-85 of theEarthrsquos oxygen

Diatoms use oil and many spines to help stay afloat in the ocean Some also form chains toincrease their ability to float Floating near the surface is important because diatoms needthe sun to produce energy and the sunlight only penetrates to approx 600 ft

The shape of a diatom is often what is used to identify it There are three major shapes

Disc-likecentric diatoms (shell radiates from a central point) Rod-like

Boat-shapedpennate diatoms

There are thousands of different phytoplankton Using the pictures on the next few pagesyou can identify some of these diatoms by their shape We have featured the most common diatoms seen in Kachemak Bay Remember that some diatom species can ldquochainuprdquo and create different shapes

Diatom - disc-like or centric SizeConscinodiscus spp top view

200-300 microm

side view

Diatom - disc-like - Chaetoceros spp Size

100-500 microm

This genus is one of the largest of marine plankton with 400 species described

Diatom - triangular Size Ditylum 250 microm

SizeDiatom - cylindrical chain 100 micromStephanopyxis

Diatom - rod-like chain Size Thalassionema 300-400 microm

Diatom - rod-like Size

Cylindrotheca 100-1000 microm

Diatom - rod-like Size Size

100 microm Psedo-nitzschiaBacillaria 100 microm

Diatom - boat-like or pennate

Protoperidinium sp

Dinoflagellates Kingdom Protista

Phylum Dinoflagellata 100-2000 microm

Taxonomy Size

Dinoflagellates are complex one-celled algaein the Protista kingdom

Energy sourceDinoflagellates are odd members of thephytoplankton community While typicallyconsidered plant-like due to their capacity tophotosynthesize they can swim using twotiny whip-like flagella like simple animalsSome even eat other organisms which mostplants are not capable of

Predators Small crustaceans fish larvae and other protists

Interesting factsSome dinoflagellates are bioluminescentcreating light when disturbed by waves boatwakes or predators

Toxic red tides are sometimes caused bymembers of this group The genus that isharmful here in Kachemak Bay isAlexandrium When large blooms of thesedinoflagellates occur fish and filter-feedinginvertebrates like clams become contaminated

The cell wall of some dinoflagellates arearmored with plates composed of cellulose

Dinoflagellate Size Ceratium spp 100 microm

Dinoflagellate SizeCeratium spp 100 microm

Phylum Arthropoda Subphylum Class Crustacea Subclass Copepoda ndash Subclass Ostracoda ndash

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Porifera ndash sponges

Phylum Cnidaria Class Hydrozoa ndash hydroids hydromedusae Class Scyphozoa ndash true jellyfish Class Anthozoa ndash sea anemones corals sea pens

Phylum Ctenophora ndash comb jellies

Phylum Platyhelminthes ndash flatworms

Phylum Nemertea ndash ribbon worms

Phylum Annelida Class Polychaete ndash polychaete worms

Phylum Sipuncula ndash peanut worms

Phylum Echiura ndash fat innkeeper

Phylum Mollusca Class Polyplacophora ndash chitons

Class Gastropoda Subclass Prosobranchia - snails

Subclass Heterobranchia Superorder Opisthobranchia ndash nudibranchs

Class Bivalvia ndash clams mussels scallops Class Cephalopoda ndash octopuses squids

copepods ostracods

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Arthropoda (continued) Subclass Malacostraca

Order Mysidacea ndash mysid shrimp Order Hemicaridea ndash cumaceans

Order Edriophthalma Suborder Isopoda ndash isopods

Suborder Amphipoda ndash amphipods Order Euphausiacea ndash krill

Order Decapoda Suborder Dendrobranchiata ndash large shrimps prawns Suborder Eukyphida ndash small shrimps Suborder Reptantia ndash crabs (+ lobsters crayfish) Class Maxillopoda Subclass Thecostraca

Order Cirripedia ndash barnacles

Phylum Brachiopoda ndash brachiopods lamp shells

Phylum Ectoprocta (Bryozoa) ndash bryozoans

Phylum Echinodermata Class Asteroidea ndash sea stars

Class Ophiuroidea ndash brittle stars Class Echinoidea ndash sea urchins Class Holothuroidea ndash sea cucumbers

Phylum Chordata Subphylum Urochordata ndash tunicates

Class Ascidiacea ndash sea squirts Class Thaliacea ndash salps

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Diatom - disc-like or centric SizeConscinodiscus spp top view

200-300 microm

side view

Diatom - disc-like - Chaetoceros spp Size

100-500 microm

This genus is one of the largest of marine plankton with 400 species described

Diatom - triangular Size Ditylum 250 microm

SizeDiatom - cylindrical chain 100 micromStephanopyxis

Diatom - rod-like chain Size Thalassionema 300-400 microm

Diatom - rod-like Size

Cylindrotheca 100-1000 microm

Diatom - rod-like Size Size

100 microm Psedo-nitzschiaBacillaria 100 microm

Diatom - boat-like or pennate

Protoperidinium sp

Dinoflagellates Kingdom Protista

Phylum Dinoflagellata 100-2000 microm

Taxonomy Size

Dinoflagellates are complex one-celled algaein the Protista kingdom

Energy sourceDinoflagellates are odd members of thephytoplankton community While typicallyconsidered plant-like due to their capacity tophotosynthesize they can swim using twotiny whip-like flagella like simple animalsSome even eat other organisms which mostplants are not capable of

Predators Small crustaceans fish larvae and other protists

Interesting factsSome dinoflagellates are bioluminescentcreating light when disturbed by waves boatwakes or predators

Toxic red tides are sometimes caused bymembers of this group The genus that isharmful here in Kachemak Bay isAlexandrium When large blooms of thesedinoflagellates occur fish and filter-feedinginvertebrates like clams become contaminated

The cell wall of some dinoflagellates arearmored with plates composed of cellulose

Dinoflagellate Size Ceratium spp 100 microm

Dinoflagellate SizeCeratium spp 100 microm

Phylum Arthropoda Subphylum Class Crustacea Subclass Copepoda ndash Subclass Ostracoda ndash

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Porifera ndash sponges

Phylum Cnidaria Class Hydrozoa ndash hydroids hydromedusae Class Scyphozoa ndash true jellyfish Class Anthozoa ndash sea anemones corals sea pens

Phylum Ctenophora ndash comb jellies

Phylum Platyhelminthes ndash flatworms

Phylum Nemertea ndash ribbon worms

Phylum Annelida Class Polychaete ndash polychaete worms

Phylum Sipuncula ndash peanut worms

Phylum Echiura ndash fat innkeeper

Phylum Mollusca Class Polyplacophora ndash chitons

Class Gastropoda Subclass Prosobranchia - snails

Subclass Heterobranchia Superorder Opisthobranchia ndash nudibranchs

Class Bivalvia ndash clams mussels scallops Class Cephalopoda ndash octopuses squids

copepods ostracods

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Arthropoda (continued) Subclass Malacostraca

Order Mysidacea ndash mysid shrimp Order Hemicaridea ndash cumaceans

Order Edriophthalma Suborder Isopoda ndash isopods

Suborder Amphipoda ndash amphipods Order Euphausiacea ndash krill

Order Decapoda Suborder Dendrobranchiata ndash large shrimps prawns Suborder Eukyphida ndash small shrimps Suborder Reptantia ndash crabs (+ lobsters crayfish) Class Maxillopoda Subclass Thecostraca

Order Cirripedia ndash barnacles

Phylum Brachiopoda ndash brachiopods lamp shells

Phylum Ectoprocta (Bryozoa) ndash bryozoans

Phylum Echinodermata Class Asteroidea ndash sea stars

Class Ophiuroidea ndash brittle stars Class Echinoidea ndash sea urchins Class Holothuroidea ndash sea cucumbers

Phylum Chordata Subphylum Urochordata ndash tunicates

Class Ascidiacea ndash sea squirts Class Thaliacea ndash salps

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Diatom - disc-like - Chaetoceros spp Size

100-500 microm

This genus is one of the largest of marine plankton with 400 species described

Diatom - triangular Size Ditylum 250 microm

SizeDiatom - cylindrical chain 100 micromStephanopyxis

Diatom - rod-like chain Size Thalassionema 300-400 microm

Diatom - rod-like Size

Cylindrotheca 100-1000 microm

Diatom - rod-like Size Size

100 microm Psedo-nitzschiaBacillaria 100 microm

Diatom - boat-like or pennate

Protoperidinium sp

Dinoflagellates Kingdom Protista

Phylum Dinoflagellata 100-2000 microm

Taxonomy Size

Dinoflagellates are complex one-celled algaein the Protista kingdom

Energy sourceDinoflagellates are odd members of thephytoplankton community While typicallyconsidered plant-like due to their capacity tophotosynthesize they can swim using twotiny whip-like flagella like simple animalsSome even eat other organisms which mostplants are not capable of

Predators Small crustaceans fish larvae and other protists

Interesting factsSome dinoflagellates are bioluminescentcreating light when disturbed by waves boatwakes or predators

Toxic red tides are sometimes caused bymembers of this group The genus that isharmful here in Kachemak Bay isAlexandrium When large blooms of thesedinoflagellates occur fish and filter-feedinginvertebrates like clams become contaminated

The cell wall of some dinoflagellates arearmored with plates composed of cellulose

Dinoflagellate Size Ceratium spp 100 microm

Dinoflagellate SizeCeratium spp 100 microm

Phylum Arthropoda Subphylum Class Crustacea Subclass Copepoda ndash Subclass Ostracoda ndash

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Porifera ndash sponges

Phylum Cnidaria Class Hydrozoa ndash hydroids hydromedusae Class Scyphozoa ndash true jellyfish Class Anthozoa ndash sea anemones corals sea pens

Phylum Ctenophora ndash comb jellies

Phylum Platyhelminthes ndash flatworms

Phylum Nemertea ndash ribbon worms

Phylum Annelida Class Polychaete ndash polychaete worms

Phylum Sipuncula ndash peanut worms

Phylum Echiura ndash fat innkeeper

Phylum Mollusca Class Polyplacophora ndash chitons

Class Gastropoda Subclass Prosobranchia - snails

Subclass Heterobranchia Superorder Opisthobranchia ndash nudibranchs

Class Bivalvia ndash clams mussels scallops Class Cephalopoda ndash octopuses squids

copepods ostracods

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Arthropoda (continued) Subclass Malacostraca

Order Mysidacea ndash mysid shrimp Order Hemicaridea ndash cumaceans

Order Edriophthalma Suborder Isopoda ndash isopods

Suborder Amphipoda ndash amphipods Order Euphausiacea ndash krill

Order Decapoda Suborder Dendrobranchiata ndash large shrimps prawns Suborder Eukyphida ndash small shrimps Suborder Reptantia ndash crabs (+ lobsters crayfish) Class Maxillopoda Subclass Thecostraca

Order Cirripedia ndash barnacles

Phylum Brachiopoda ndash brachiopods lamp shells

Phylum Ectoprocta (Bryozoa) ndash bryozoans

Phylum Echinodermata Class Asteroidea ndash sea stars

Class Ophiuroidea ndash brittle stars Class Echinoidea ndash sea urchins Class Holothuroidea ndash sea cucumbers

Phylum Chordata Subphylum Urochordata ndash tunicates

Class Ascidiacea ndash sea squirts Class Thaliacea ndash salps

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Diatom - triangular Size Ditylum 250 microm

SizeDiatom - cylindrical chain 100 micromStephanopyxis

Diatom - rod-like chain Size Thalassionema 300-400 microm

Diatom - rod-like Size

Cylindrotheca 100-1000 microm

Diatom - rod-like Size Size

100 microm Psedo-nitzschiaBacillaria 100 microm

Diatom - boat-like or pennate

Protoperidinium sp

Dinoflagellates Kingdom Protista

Phylum Dinoflagellata 100-2000 microm

Taxonomy Size

Dinoflagellates are complex one-celled algaein the Protista kingdom

Energy sourceDinoflagellates are odd members of thephytoplankton community While typicallyconsidered plant-like due to their capacity tophotosynthesize they can swim using twotiny whip-like flagella like simple animalsSome even eat other organisms which mostplants are not capable of

Predators Small crustaceans fish larvae and other protists

Interesting factsSome dinoflagellates are bioluminescentcreating light when disturbed by waves boatwakes or predators

Toxic red tides are sometimes caused bymembers of this group The genus that isharmful here in Kachemak Bay isAlexandrium When large blooms of thesedinoflagellates occur fish and filter-feedinginvertebrates like clams become contaminated

The cell wall of some dinoflagellates arearmored with plates composed of cellulose

Dinoflagellate Size Ceratium spp 100 microm

Dinoflagellate SizeCeratium spp 100 microm

Phylum Arthropoda Subphylum Class Crustacea Subclass Copepoda ndash Subclass Ostracoda ndash

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Porifera ndash sponges

Phylum Cnidaria Class Hydrozoa ndash hydroids hydromedusae Class Scyphozoa ndash true jellyfish Class Anthozoa ndash sea anemones corals sea pens

Phylum Ctenophora ndash comb jellies

Phylum Platyhelminthes ndash flatworms

Phylum Nemertea ndash ribbon worms

Phylum Annelida Class Polychaete ndash polychaete worms

Phylum Sipuncula ndash peanut worms

Phylum Echiura ndash fat innkeeper

Phylum Mollusca Class Polyplacophora ndash chitons

Class Gastropoda Subclass Prosobranchia - snails

Subclass Heterobranchia Superorder Opisthobranchia ndash nudibranchs

Class Bivalvia ndash clams mussels scallops Class Cephalopoda ndash octopuses squids

copepods ostracods

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Arthropoda (continued) Subclass Malacostraca

Order Mysidacea ndash mysid shrimp Order Hemicaridea ndash cumaceans

Order Edriophthalma Suborder Isopoda ndash isopods

Suborder Amphipoda ndash amphipods Order Euphausiacea ndash krill

Order Decapoda Suborder Dendrobranchiata ndash large shrimps prawns Suborder Eukyphida ndash small shrimps Suborder Reptantia ndash crabs (+ lobsters crayfish) Class Maxillopoda Subclass Thecostraca

Order Cirripedia ndash barnacles

Phylum Brachiopoda ndash brachiopods lamp shells

Phylum Ectoprocta (Bryozoa) ndash bryozoans

Phylum Echinodermata Class Asteroidea ndash sea stars

Class Ophiuroidea ndash brittle stars Class Echinoidea ndash sea urchins Class Holothuroidea ndash sea cucumbers

Phylum Chordata Subphylum Urochordata ndash tunicates

Class Ascidiacea ndash sea squirts Class Thaliacea ndash salps

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Diatom - rod-like chain Size Thalassionema 300-400 microm

Diatom - rod-like Size

Cylindrotheca 100-1000 microm

Diatom - rod-like Size Size

100 microm Psedo-nitzschiaBacillaria 100 microm

Diatom - boat-like or pennate

Protoperidinium sp

Dinoflagellates Kingdom Protista

Phylum Dinoflagellata 100-2000 microm

Taxonomy Size

Dinoflagellates are complex one-celled algaein the Protista kingdom

Energy sourceDinoflagellates are odd members of thephytoplankton community While typicallyconsidered plant-like due to their capacity tophotosynthesize they can swim using twotiny whip-like flagella like simple animalsSome even eat other organisms which mostplants are not capable of

Predators Small crustaceans fish larvae and other protists

Interesting factsSome dinoflagellates are bioluminescentcreating light when disturbed by waves boatwakes or predators

Toxic red tides are sometimes caused bymembers of this group The genus that isharmful here in Kachemak Bay isAlexandrium When large blooms of thesedinoflagellates occur fish and filter-feedinginvertebrates like clams become contaminated

The cell wall of some dinoflagellates arearmored with plates composed of cellulose

Dinoflagellate Size Ceratium spp 100 microm

Dinoflagellate SizeCeratium spp 100 microm

Phylum Arthropoda Subphylum Class Crustacea Subclass Copepoda ndash Subclass Ostracoda ndash

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Porifera ndash sponges

Phylum Cnidaria Class Hydrozoa ndash hydroids hydromedusae Class Scyphozoa ndash true jellyfish Class Anthozoa ndash sea anemones corals sea pens

Phylum Ctenophora ndash comb jellies

Phylum Platyhelminthes ndash flatworms

Phylum Nemertea ndash ribbon worms

Phylum Annelida Class Polychaete ndash polychaete worms

Phylum Sipuncula ndash peanut worms

Phylum Echiura ndash fat innkeeper

Phylum Mollusca Class Polyplacophora ndash chitons

Class Gastropoda Subclass Prosobranchia - snails

Subclass Heterobranchia Superorder Opisthobranchia ndash nudibranchs

Class Bivalvia ndash clams mussels scallops Class Cephalopoda ndash octopuses squids

copepods ostracods

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Arthropoda (continued) Subclass Malacostraca

Order Mysidacea ndash mysid shrimp Order Hemicaridea ndash cumaceans

Order Edriophthalma Suborder Isopoda ndash isopods

Suborder Amphipoda ndash amphipods Order Euphausiacea ndash krill

Order Decapoda Suborder Dendrobranchiata ndash large shrimps prawns Suborder Eukyphida ndash small shrimps Suborder Reptantia ndash crabs (+ lobsters crayfish) Class Maxillopoda Subclass Thecostraca

Order Cirripedia ndash barnacles

Phylum Brachiopoda ndash brachiopods lamp shells

Phylum Ectoprocta (Bryozoa) ndash bryozoans

Phylum Echinodermata Class Asteroidea ndash sea stars

Class Ophiuroidea ndash brittle stars Class Echinoidea ndash sea urchins Class Holothuroidea ndash sea cucumbers

Phylum Chordata Subphylum Urochordata ndash tunicates

Class Ascidiacea ndash sea squirts Class Thaliacea ndash salps

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Diatom - rod-like Size Size

100 microm Psedo-nitzschiaBacillaria 100 microm

Diatom - boat-like or pennate

Protoperidinium sp

Dinoflagellates Kingdom Protista

Phylum Dinoflagellata 100-2000 microm

Taxonomy Size

Dinoflagellates are complex one-celled algaein the Protista kingdom

Energy sourceDinoflagellates are odd members of thephytoplankton community While typicallyconsidered plant-like due to their capacity tophotosynthesize they can swim using twotiny whip-like flagella like simple animalsSome even eat other organisms which mostplants are not capable of

Predators Small crustaceans fish larvae and other protists

Interesting factsSome dinoflagellates are bioluminescentcreating light when disturbed by waves boatwakes or predators

Toxic red tides are sometimes caused bymembers of this group The genus that isharmful here in Kachemak Bay isAlexandrium When large blooms of thesedinoflagellates occur fish and filter-feedinginvertebrates like clams become contaminated

The cell wall of some dinoflagellates arearmored with plates composed of cellulose

Dinoflagellate Size Ceratium spp 100 microm

Dinoflagellate SizeCeratium spp 100 microm

Phylum Arthropoda Subphylum Class Crustacea Subclass Copepoda ndash Subclass Ostracoda ndash

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Porifera ndash sponges

Phylum Cnidaria Class Hydrozoa ndash hydroids hydromedusae Class Scyphozoa ndash true jellyfish Class Anthozoa ndash sea anemones corals sea pens

Phylum Ctenophora ndash comb jellies

Phylum Platyhelminthes ndash flatworms

Phylum Nemertea ndash ribbon worms

Phylum Annelida Class Polychaete ndash polychaete worms

Phylum Sipuncula ndash peanut worms

Phylum Echiura ndash fat innkeeper

Phylum Mollusca Class Polyplacophora ndash chitons

Class Gastropoda Subclass Prosobranchia - snails

Subclass Heterobranchia Superorder Opisthobranchia ndash nudibranchs

Class Bivalvia ndash clams mussels scallops Class Cephalopoda ndash octopuses squids

copepods ostracods

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Arthropoda (continued) Subclass Malacostraca

Order Mysidacea ndash mysid shrimp Order Hemicaridea ndash cumaceans

Order Edriophthalma Suborder Isopoda ndash isopods

Suborder Amphipoda ndash amphipods Order Euphausiacea ndash krill

Order Decapoda Suborder Dendrobranchiata ndash large shrimps prawns Suborder Eukyphida ndash small shrimps Suborder Reptantia ndash crabs (+ lobsters crayfish) Class Maxillopoda Subclass Thecostraca

Order Cirripedia ndash barnacles

Phylum Brachiopoda ndash brachiopods lamp shells

Phylum Ectoprocta (Bryozoa) ndash bryozoans

Phylum Echinodermata Class Asteroidea ndash sea stars

Class Ophiuroidea ndash brittle stars Class Echinoidea ndash sea urchins Class Holothuroidea ndash sea cucumbers

Phylum Chordata Subphylum Urochordata ndash tunicates

Class Ascidiacea ndash sea squirts Class Thaliacea ndash salps

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Protoperidinium sp

Dinoflagellates Kingdom Protista

Phylum Dinoflagellata 100-2000 microm

Taxonomy Size

Dinoflagellates are complex one-celled algaein the Protista kingdom

Energy sourceDinoflagellates are odd members of thephytoplankton community While typicallyconsidered plant-like due to their capacity tophotosynthesize they can swim using twotiny whip-like flagella like simple animalsSome even eat other organisms which mostplants are not capable of

Predators Small crustaceans fish larvae and other protists

Interesting factsSome dinoflagellates are bioluminescentcreating light when disturbed by waves boatwakes or predators

Toxic red tides are sometimes caused bymembers of this group The genus that isharmful here in Kachemak Bay isAlexandrium When large blooms of thesedinoflagellates occur fish and filter-feedinginvertebrates like clams become contaminated

The cell wall of some dinoflagellates arearmored with plates composed of cellulose

Dinoflagellate Size Ceratium spp 100 microm

Dinoflagellate SizeCeratium spp 100 microm

Phylum Arthropoda Subphylum Class Crustacea Subclass Copepoda ndash Subclass Ostracoda ndash

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Porifera ndash sponges

Phylum Cnidaria Class Hydrozoa ndash hydroids hydromedusae Class Scyphozoa ndash true jellyfish Class Anthozoa ndash sea anemones corals sea pens

Phylum Ctenophora ndash comb jellies

Phylum Platyhelminthes ndash flatworms

Phylum Nemertea ndash ribbon worms

Phylum Annelida Class Polychaete ndash polychaete worms

Phylum Sipuncula ndash peanut worms

Phylum Echiura ndash fat innkeeper

Phylum Mollusca Class Polyplacophora ndash chitons

Class Gastropoda Subclass Prosobranchia - snails

Subclass Heterobranchia Superorder Opisthobranchia ndash nudibranchs

Class Bivalvia ndash clams mussels scallops Class Cephalopoda ndash octopuses squids

copepods ostracods

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Arthropoda (continued) Subclass Malacostraca

Order Mysidacea ndash mysid shrimp Order Hemicaridea ndash cumaceans

Order Edriophthalma Suborder Isopoda ndash isopods

Suborder Amphipoda ndash amphipods Order Euphausiacea ndash krill

Order Decapoda Suborder Dendrobranchiata ndash large shrimps prawns Suborder Eukyphida ndash small shrimps Suborder Reptantia ndash crabs (+ lobsters crayfish) Class Maxillopoda Subclass Thecostraca

Order Cirripedia ndash barnacles

Phylum Brachiopoda ndash brachiopods lamp shells

Phylum Ectoprocta (Bryozoa) ndash bryozoans

Phylum Echinodermata Class Asteroidea ndash sea stars

Class Ophiuroidea ndash brittle stars Class Echinoidea ndash sea urchins Class Holothuroidea ndash sea cucumbers

Phylum Chordata Subphylum Urochordata ndash tunicates

Class Ascidiacea ndash sea squirts Class Thaliacea ndash salps

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Dinoflagellate Size Ceratium spp 100 microm

Dinoflagellate SizeCeratium spp 100 microm

Phylum Arthropoda Subphylum Class Crustacea Subclass Copepoda ndash Subclass Ostracoda ndash

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Porifera ndash sponges

Phylum Cnidaria Class Hydrozoa ndash hydroids hydromedusae Class Scyphozoa ndash true jellyfish Class Anthozoa ndash sea anemones corals sea pens

Phylum Ctenophora ndash comb jellies

Phylum Platyhelminthes ndash flatworms

Phylum Nemertea ndash ribbon worms

Phylum Annelida Class Polychaete ndash polychaete worms

Phylum Sipuncula ndash peanut worms

Phylum Echiura ndash fat innkeeper

Phylum Mollusca Class Polyplacophora ndash chitons

Class Gastropoda Subclass Prosobranchia - snails

Subclass Heterobranchia Superorder Opisthobranchia ndash nudibranchs

Class Bivalvia ndash clams mussels scallops Class Cephalopoda ndash octopuses squids

copepods ostracods

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Arthropoda (continued) Subclass Malacostraca

Order Mysidacea ndash mysid shrimp Order Hemicaridea ndash cumaceans

Order Edriophthalma Suborder Isopoda ndash isopods

Suborder Amphipoda ndash amphipods Order Euphausiacea ndash krill

Order Decapoda Suborder Dendrobranchiata ndash large shrimps prawns Suborder Eukyphida ndash small shrimps Suborder Reptantia ndash crabs (+ lobsters crayfish) Class Maxillopoda Subclass Thecostraca

Order Cirripedia ndash barnacles

Phylum Brachiopoda ndash brachiopods lamp shells

Phylum Ectoprocta (Bryozoa) ndash bryozoans

Phylum Echinodermata Class Asteroidea ndash sea stars

Class Ophiuroidea ndash brittle stars Class Echinoidea ndash sea urchins Class Holothuroidea ndash sea cucumbers

Phylum Chordata Subphylum Urochordata ndash tunicates

Class Ascidiacea ndash sea squirts Class Thaliacea ndash salps

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Phylum Arthropoda Subphylum Class Crustacea Subclass Copepoda ndash Subclass Ostracoda ndash

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Porifera ndash sponges

Phylum Cnidaria Class Hydrozoa ndash hydroids hydromedusae Class Scyphozoa ndash true jellyfish Class Anthozoa ndash sea anemones corals sea pens

Phylum Ctenophora ndash comb jellies

Phylum Platyhelminthes ndash flatworms

Phylum Nemertea ndash ribbon worms

Phylum Annelida Class Polychaete ndash polychaete worms

Phylum Sipuncula ndash peanut worms

Phylum Echiura ndash fat innkeeper

Phylum Mollusca Class Polyplacophora ndash chitons

Class Gastropoda Subclass Prosobranchia - snails

Subclass Heterobranchia Superorder Opisthobranchia ndash nudibranchs

Class Bivalvia ndash clams mussels scallops Class Cephalopoda ndash octopuses squids

copepods ostracods

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Arthropoda (continued) Subclass Malacostraca

Order Mysidacea ndash mysid shrimp Order Hemicaridea ndash cumaceans

Order Edriophthalma Suborder Isopoda ndash isopods

Suborder Amphipoda ndash amphipods Order Euphausiacea ndash krill

Order Decapoda Suborder Dendrobranchiata ndash large shrimps prawns Suborder Eukyphida ndash small shrimps Suborder Reptantia ndash crabs (+ lobsters crayfish) Class Maxillopoda Subclass Thecostraca

Order Cirripedia ndash barnacles

Phylum Brachiopoda ndash brachiopods lamp shells

Phylum Ectoprocta (Bryozoa) ndash bryozoans

Phylum Echinodermata Class Asteroidea ndash sea stars

Class Ophiuroidea ndash brittle stars Class Echinoidea ndash sea urchins Class Holothuroidea ndash sea cucumbers

Phylum Chordata Subphylum Urochordata ndash tunicates

Class Ascidiacea ndash sea squirts Class Thaliacea ndash salps

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Zooplankton Taxonomy From Kingdom Animalia

PLANKTONIC SPECIES INCLUDED IN THIS TAXON

Phylum Arthropoda (continued) Subclass Malacostraca

Order Mysidacea ndash mysid shrimp Order Hemicaridea ndash cumaceans

Order Edriophthalma Suborder Isopoda ndash isopods

Suborder Amphipoda ndash amphipods Order Euphausiacea ndash krill

Order Decapoda Suborder Dendrobranchiata ndash large shrimps prawns Suborder Eukyphida ndash small shrimps Suborder Reptantia ndash crabs (+ lobsters crayfish) Class Maxillopoda Subclass Thecostraca

Order Cirripedia ndash barnacles

Phylum Brachiopoda ndash brachiopods lamp shells

Phylum Ectoprocta (Bryozoa) ndash bryozoans

Phylum Echinodermata Class Asteroidea ndash sea stars

Class Ophiuroidea ndash brittle stars Class Echinoidea ndash sea urchins Class Holothuroidea ndash sea cucumbers

Phylum Chordata Subphylum Urochordata ndash tunicates

Class Ascidiacea ndash sea squirts Class Thaliacea ndash salps

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Parafavella sp

Ciliates Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum CiliophoraClass Spiotrichea

20-300 microm

Taxonomy Size

A ciliate is a single-celled organism belong-ing to a group called protists It is recog-nized for having many cilia that it uses forlocomotion and to bring food to its icyto-stome or lsquocellular mouthrsquo Ciliates vary inshape and size They are found in all waterenvironments and often sediments

Energy sourceTiny piconanophytoplankton and bacteria

Predators Larger zooplankton - including copepodsfish larvae ctenophores dinoflagellatesand jellies - and invertebrate filter feeders

Viewing tipsLook for a clear vase or barrel shape withcilia at the opening

Interesting factsBecause ciliates provide a link beween thetiniest bacteria (piconanoplankton) and thelarger zooplankton that eat ciliates theyhave a major effect on the way the ocean ecosystems provide nutrients and energy The more piconanoplankton the moreciliates there are in the water

Tintinnopsis sp

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Radiolarians Holoplankton

(spends entire life cycle as plankton)

Kingdom ProtistaPhylum ProtozoaClass Sarcodinea

Subclass ActinopodaOrder Radiolaria

30-300 microm

Taxonomy Size

Radiolarians are tiny single-celled organ-isms with radiating spines calledaxospodes Their skeleton is made of silicon dioxide or strontium sulfate They areentirely marine and primarily planktonicTheir skeletons sink to the ocean floor where under pressure and over time theymay form radiolarian chert a rock formationwhich can be seen on the south side of Kachemak Bay

Energy sourcePhytoplankton and zooplankton includingbacteria and detritus

Predators Larger zooplankton and invertebrate filterfeeders

Viewing tipsRarely seen in most Kachemak Bay plank-ton tows

Interesting factsThe name radiolarian comes from their radial symmetry

Cytoplasm extends from the inside to theoutside of their body

Radiolarians capture prey with temporaryprojections of their cytoplasm called psue-dopodia

Their presence in rock formations indicates

live radiolarian with cytoplasm sticking out

radiolarian skeleton

radiolarian chert

that the rocks were formed from ocean floor

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

unknown cydippid larva

sea gooseberry Pluerobrachia

bachei

Ctenophores Comb Jellies

Holoplankton(spends entire life cycle as plankton)

Kingdom Animalia

Phylum Ctenophora 1-4 mm

Taxonomy Size

Pronounced with a silent c as ldquoteen-o-fourrdquo These macrozooplankton seem a lot likejellies but are not Ctenophores lack stingingcells and are harmless to humans

Energy sourceCopepods fish eggs mollusc larvae and otherctenophores They are considered ambushpredators using their sticky tentacles orexpandable sticky lobes to capture zooplank-ton

Predators Sea nettle and other jellies fish sea turtlesand other comb jellies

SeasonalityLate summer

Viewing tipsLook for eight iridescent bands of cilia Theycan be torn in the sample and you may onlysee part of them

Interesting factsThere are no freshwater species

If you hold a flashlight over a live ctenophorethe waving cilia will reflect beautiful rainbowcolors This is not bioluminescence (whichmany ctenophores do have)

Being transparent helps comb jellies avoidpredators

Ctenophores move in the direction of theirmouth

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

) do not

Polychaetes Worm Larvae

Meroplankton(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum AnnelidaClass Polychaete

Taxonomy Size

The best known annelid (segmented worm)

ment (known as the trochophoreeat but are nourished by a yolk from theegg Some polychaetes emerge from theegg as adults

Energy sourceZooplankton and phytoplankton

Predators Larger zooplankton and small fish

Viewing tipsTrochophores move with a spinning motion their cilia propelling them This movementcan help you identify them

Interesting factsThe polychaetes have amazing regenera-tive abilities They have been found toregenerate one body segment in a day

Polychaetes seem to align their reproduc-tion with lunar phases though exactly howis not understood

100 microm-6 mm

is the earthworm The 8000 known speciesof polychaete worms make up one class ofannelids Polychaete means many bristlesand they are so named because of the ciliathey use to move and eat with Most poly-chaete larvae in the early stage of develop-

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Oweniidae larva Oweniidae larva

polychaete larva with egg polychaete larva

Spionidae larva Syllidae larva

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Snail Veligers Meroplankton

(spends beginning of life cycle as plankton) Taxonomy Size

5-3 mmKingdom AnimaliaPhylum MolluscaClass Gastropoda

The planktonic larva of most gastropods isthe veliger A tiny fragile shell encases theciliated velum enabling the larva to staysuspended in the water column and eat bybeating its cilia

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

SeasonalityGastropod larvae usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsSome veligers are dark in color and easy tosee in a sample When the velum is retractedinside the shell they sink to the bottom of thesample jar If you swirl the jar in a circle theveligers may congregate in the centermaking them easy to capture with aneyedropper

The velum is often retracted and you seeonly the shell

adult snail

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Bivalve Veligers Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Mollusca

Class Bivalvia 600-1000 microm

Taxonomy Size

Shortly after an egg from a clam or otherbivalve hatches it develops cilia (hair-likestructures) which allow it to move within thewater column Clam larvae or veligers also develop two very thin shells called valveswhich catagorize them as bivalve members of the Mollusca phylum

Energy sourcePhytoplankton

Predators Fish larvae and invertebrate filter feeders

Life spanBivalve veligers usually spend 1-3 weeks asplankton before they settle to the bottom

Viewing tipsThe plankton veliger exhibit a classic clam-likeshape and are usually colorless

Interesting factsCilia fringe an organ called the velum which can sometimes be seen outside the shell

A foot develops which may also be spottedon the planktonic veliger larva

adult bivalve

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Cladocerans Water Fleas

Holoplankton (spends entire life cycle as plankton)

less than 2 mmKingdom AnimaliaPhylum Arthropoda

Class CrustaceaOrder Onychopoda

Taxonomy Size

Energy sourceDiatoms dinoflagellates ciliates and cope-pod larvae

Predators Larger zooplankton

Viewing tipsLook for the huge eyespot and the conspicu-ous external antennae

Interesting factsCladoceran young have no free larval formsinstead they are brooded within theirmotherrsquos carapace

They have an unusual mode of reproductioncalled parthenogenesis lsquoParthenogenisisrsquo(meaning lsquopure beginningrsquo) is where thefemale is the only parent of the offspring and there is no male involved in their conception

Podon sp

Podon sp with eggs

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Copepoda

avgerage size 1-2 mm(1000-2000 microm)

can be as small as 2 mm and as large as 10 mm

Taxonomy SizeCopepodsHoloplankton

(spends entire life cycle as plankton)

Copepods are macroplanktonic crustaceans found in both fresh and salt water Theyhave legs antennae and a segmented body

Energy sourcePrimarily phytoplankton but also microzooplankton

Predators Arrow worms larval fish (especially herring) jellies filter-feeding benthic invertebratesand salmon

Life spanOne week to two years (depending on species)

Life cycleAfter copepods emerge from eggs they go through many changes as they matureLike all crustaceans copepods molt their exoskeleton The first five to six moltingstages are called the naupliar stages nauplii are commonly seen in our planktonsamples There are also five or six copepodite stages before they areconsidered mature these stages look pretty much like adults

Viewing tipsCopepods have a single eyespot in the middle of their heads This simple eye candistinguish between light and dark Often copepod nauplii are mistaken for barnaclelarvae If the body shape is more rounded than shield-shaped and there are no lsquohornsrsquoon the head yoursquore probably looking at a copepod nauplius If your copepod is alivemake the drop on your slide small so it wonrsquot swim out of your range of view Often acopepod will be on its side and look like the photo below

Interesting facts Copepods are the most numerous multi-celled animal in the

ocean and possibly the most numerous on Earth

A single copepod may eat from 11000 to 373000 diatoms in 24 hours

There are over 24000 species of copepods The three most common orders are Calanoida - Abundant offshore with long antennae four abdominal segments and eggs in a single cluster Harpacticoida - Like to live nearshore and on the bottom Harpacticoids have shortened antennae and a less noticable division between body regions Cyclopoida - Only a few species They have shortened antennae and 5-6 abdominal segments Eggs are stored in paired sacs

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

SizeJuvenile Copepod

naupliar stage 200-300 microm

SizeAdult Copepods

Calanoid spp 2-5 mm

Harpacticoid spp

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

barnacle naupli

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass Maxillopoda

Subclass ThecostracaOrder Cirripedia

naupliar stages200-500 microm

Taxonomy Size

Barnacles are crustaceans like shrimp andcrabs A larval barnacle or nauplius goesthrough six stages before metamorphosinginto a cyprid and then the adult form Naupliiare common in plankton samples fromestuaries

Energy sourcePhytoplankton

Predators Invertebrate filter feeders (including adultbarnacles)

Viewing tipsBarnacle nauplii have an eyespot and threepairs of appendages They can bedistinguished from other similar-lookingzooplankton by hornlike projections on theirshoulders and shield shaped back In aplankton sample they tend to swim in circlesupside down

Barnacle molts are also found in planktonsamples but can be broken up making themolts difficult to identify Samples from aharbor or ones taken when many barnaclesmolt their exoskeletons simultaneously can bequite full of these molts

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Barnacles Meroplankton

(spends beginning of life cycle as plankton)

cyprid stage500-1000 microm

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MaxillopodaOrder Thecostraca

Order Cirripedia

Taxonomy Size

The cyprid larval stage develops after thenaupliar stages seen on the previous pageThe cyprid is adapted for selecting a suitablesurface to settle allowing it the best chanceto survive as an adult

Energy sourceThis is a non-feeding stage

Life spanThis stage can exists for up to thirteen days

Viewing tipsA cyprid is football-shaped with a transparentcovering You may see golden oil globulesinside and the legs may or may not bevisible

Interesting factsA cyprid will actually walk around on asurface (substrate) looking for a place tosettle Once a site is selected the barnacle will cement itself into place and undergo adramatic metamorphosis into the adult form

adult barnacle

barnacle cyprid

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

crab zoea

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum CrustaceaClass MalacostracaSubclass Decopoda

zoeal stages200-500 microm

Taxonomy Size

After emerging from the egg the first larvalstages of a crab are called the zoeal stages

Energy sourcePhytoplankton

Predators Invertebrate filter feeders and larval fish

SeasonalitySome female crabs release their eggs on thelargest tides in April or May Zoea can beseen from January through July in planktonsamples The amount of time spent as a zoeadepending on how much and what kind ofphytoplankton it can find to eat

Viewing tipsIt can be easy to confuse crab zoea withcopepods and shrimp Look for the rostrum a spiny projection on a crab zoearsquos carapaceYou may need to turn the zoea over to see therostrum The spikes on the tail are importantfor identification of genus and species

Interesting factsCrab larvae have compound eyes like insectsand can see up and down at the same time

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

Crabs Meroplankton

(spends beginning of life cycle as plankton)

Kingdom AnimaliaPhylum Arthropoda

Subphylum Crustacea 1-7 mmClass MalacostracaSubclass Decopoda

megalopal stage

Taxonomy Size

After several larval zoeal stages a youngcrab molts into the megalopal stage

Energy sourcePhytoplankton

Predators Salmon herring pollock and invertebratefilter feeders

SeasonalityA crab spends from 1-10 months as amegalop again depending on how much andwhat kind of phytoplankton it can find to eat

Viewing tipsCrab megalops are easy to identify They arelarge and have the recognizable shape of acrab Their tail or telson may or may not bevisible If it is already tucked up under theabdomen the megalop is ready to settle tothe bottom

Interesting factsAdult salmon will move into estuaries to feed exclusively on crab megalops

When a megalop molts into its first adult crabstage it no longer is planktonic since it cannotstay suspended

adult crab

crab megalop

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System

HIGH SEAS DRIFTERS PLANKTON GUIDE Kachemak Bay Research Reserve ADFampG Sport Fish Division

95 Sterling Hwy Suite 2 Homer AK 99603

(907) 235-4799 wwwkbayrrorg

2008

PlanktoPlanktonn illuillustrations bystrations by CatieCatie BurschBursch Photos byPhotos by Homer High SchoolHomer High School Advanced Science students ampAdvanced Science students amp KachKachemakemak BayBay RReesearch Reserve staffsearch Reserve staff

The US Fish and Wildlife Servicersquos State Wildlife Grants program provided partial funding for production of this document

The Alaska Department of Fish and Game administers all programs and activities free from discrimination based on race color national origin age sex religion marital status pregnancy parenthood or disability The department administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964 Section 504 of the Rehabilitation Act of 1973 Title II of the Americans with Disabilities Act of 1990 the Age Discrimination Act of 1975 and Title IX of the Education Amendments of 1972

If you believe you have been discriminated against in any program activity or facility or if you desire further information please write to ADFampG PO Box 25526 Juneau AK 99802-5526 US Fish and Wildlife Service 4040 N Fairfax Drive Suite 300 Webb Arlington VA 22203 or OEO US Department of the Interior Washington DC 20240

For information on alternative formats for this and other department publications please contact the department ADA Coordinator at (voice) 907-465-4120 (TDD) 907-465-3646 or (FAX) 907-465-2440

Kachemak Bay Research Reserve is a unit of the National Estuarine Research Reserve System