Watch these 3 video clips…or watch Wolves of the Sea before showing the PPT. Orca (about 2...
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Transcript of Watch these 3 video clips…or watch Wolves of the Sea before showing the PPT. Orca (about 2...
Watch these 3 video clips…or Watch these 3 video clips…or watch Wolves of the Sea watch Wolves of the Sea before showing the PPT.before showing the PPT.
Orca (about 2 minutes)Orca (about 2 minutes)
http://www.youtube.com/watch?v=RnNv2VsKPgchttp://www.youtube.com/watch?v=RnNv2VsKPgc
Orca hunting sea lion pups (3 minutes)Orca hunting sea lion pups (3 minutes)
http://www.youtube.com/watch?v=DWsN63PRCW8http://www.youtube.com/watch?v=DWsN63PRCW8
Orca – cooperatively hunting herring and salmon (about 3 minutes)Orca – cooperatively hunting herring and salmon (about 3 minutes)
http://animal.discovery.com/videos/the-ultimate-guide-to-dolphins-orcas-cooperate-to-catch-fish.htmlhttp://animal.discovery.com/videos/the-ultimate-guide-to-dolphins-orcas-cooperate-to-catch-fish.html
Students should take notes during the PPT Students should take notes during the PPT (slides 2-9) in their Orcas booklet.(slides 2-9) in their Orcas booklet.
Case study of Bioaccumulation and Case study of Bioaccumulation and Biomagnification– Biomagnification–
Orcas - endangered species of Orcas - endangered species of Puget SoundPuget Sound
Orcas (a.k.a. killer whales)Orcas (a.k.a. killer whales)
Scientific name: Scientific name: Orcinus orcaOrcinus orca
Largest member of Largest member of dolphin familydolphin family
Identifying traits:Identifying traits: Height of dorsal finHeight of dorsal fin Saddle patch behind Saddle patch behind
dorsal findorsal fin White patches on White patches on
sides, belly, behind sides, belly, behind eyeseyes
Orca biologyOrca biology
Birth weight: around 400 Birth weight: around 400 lbslbs
Adult weight – between Adult weight – between 2.5 – 7 tons2.5 – 7 tons Males larger than femalesMales larger than females
Lifespan:Lifespan: Females: can live to over 60 Females: can live to over 60
yearsyears Males: live around 40 yearsMales: live around 40 years
Natural HistoryNatural History Found in all seas, including Arctic and tropicsFound in all seas, including Arctic and tropics Travel in pods: 3 - >150 individualsTravel in pods: 3 - >150 individuals Main food:Main food:
FishFish SquidSquid Marine mammalsMarine mammals
Transient vs. Resident OrcasTransient vs. Resident Orcas 2 major subspecies of orca2 major subspecies of orca Transient orcas:Transient orcas:
Live offshoreLive offshore Feed mostly on marine mammalsFeed mostly on marine mammals Small pods of 3-5 individualsSmall pods of 3-5 individuals Tend to be very quietTend to be very quiet
Resident orcas:Resident orcas: Live near shoreLive near shore Feed mostly on fish (esp. salmon)Feed mostly on fish (esp. salmon) Large pods: >20 individualsLarge pods: >20 individuals Vocalize oftenVocalize often
Puget Sound Resident OrcasPuget Sound Resident Orcas Live in extended familial units called podsLive in extended familial units called pods Pods are matriarchal in structurePods are matriarchal in structure
Oldest female is the grandmother of other orcas in podOldest female is the grandmother of other orcas in pod
Puget sound resident orcasPuget sound resident orcas 3 pods – J, K, L3 pods – J, K, L Summer around San Juan islandsSummer around San Juan islands Winter on Winter on
the outer coastthe outer coast
Status of Southern Resident OrcasStatus of Southern Resident Orcas 1995-2000: about 20% of 1995-2000: about 20% of
southern resident orcas died – southern resident orcas died – dropping to a low of 78 orcas dropping to a low of 78 orcas by 2011. by 2011.
Many females of reproductive Many females of reproductive age are not producing viable age are not producing viable youngyoung
Young males: dying rapidlyYoung males: dying rapidly Few males left in entire Few males left in entire
communitycommunity Listed as endangered species Listed as endangered species
in 2005 – at risk of extinctionin 2005 – at risk of extinction
At the same time, the Northern Resident and Transient populations seem to be stable.
Status of Southern Resident OrcasStatus of Southern Resident Orcas
This year 5 calves have This year 5 calves have been born, most recently been born, most recently this female (pictured) in this female (pictured) in early September. Although early September. Although about half of all calves die about half of all calves die within the first year, the within the first year, the resident population is now resident population is now at 82 organisms.at 82 organisms.http://bcove.me/0461vtwi
Threats to OrcasThreats to Orcas Decreasing food supply Decreasing food supply
wild salmon are also listed as an endangered specieswild salmon are also listed as an endangered species DisturbanceDisturbance
Physical (harassment by whale watching vessels)Physical (harassment by whale watching vessels) Acoustic (low/mid frequency sonar, drilling, dredging)Acoustic (low/mid frequency sonar, drilling, dredging)
• Interferes with echolocationInterferes with echolocation
Pollution – bioaccumulationPollution – bioaccumulation
Historic threats Historic threats HuntingHunting Captured for captivity in marine parksCaptured for captivity in marine parks
STOP HERE and have students make a food STOP HERE and have students make a food web in their booklet.web in their booklet.
PollutantsPollutants
PollutantPollutant: : any agent that adversely affects the any agent that adversely affects the health, survival, or activities of living organisms. health, survival, or activities of living organisms.
How do pollutants enter environment?How do pollutants enter environment? Point source pollution Point source pollution ––
highly concentrated discharge highly concentrated discharge coming from a specific locationcoming from a specific location Factories, power plants, sewage Factories, power plants, sewage
treatment plantstreatment plants
Non-point source pollution Non-point source pollution – – diffuse sources of pollutantsdiffuse sources of pollutants Runoff Runoff from farms, roads, golf from farms, roads, golf
courses, homes, etccourses, homes, etc
All pollutants eventually All pollutants eventually end up in the ocean end up in the ocean
Types of pollutantsTypes of pollutants Water soluble pollutantsWater soluble pollutants
Move rapidly and widely through an environmentMove rapidly and widely through an environment
Fat soluble pollutantsFat soluble pollutants Tend to have much longer effectsTend to have much longer effects Penetrate into organism’s tissues and cellsPenetrate into organism’s tissues and cells
• Stored in lipidsStored in lipids• Protected from metabolic breakdownProtected from metabolic breakdown• Passed via breast milk to young in mammalsPassed via breast milk to young in mammals
Pollutant persistencePollutant persistencePersistencePersistence = how long it takes to = how long it takes to
breakdown(degrade) and be removed breakdown(degrade) and be removed from the ecosystemfrom the ecosystem
Some compounds are very unstable and Some compounds are very unstable and degrade rapidlydegrade rapidly, thus concentrations , thus concentrations decline rapidly over timedecline rapidly over time
Other compounds are specifically Other compounds are specifically designed to designed to resist degradation resist degradation (don’t (don’t break-down easily)break-down easily) Can have severe impacts long after they are Can have severe impacts long after they are
introducedintroduced
POPsPOPs
PPersistant ersistant OOrganic rganic PPollutantsollutants synthetic organic compoundssynthetic organic compounds resist environmental degradation resist environmental degradation used in various products (from electronics to used in various products (from electronics to
cars) cars) Examples of POPs include PCBs and DDTExamples of POPs include PCBs and DDT Can have very long term effects in an Can have very long term effects in an
ecosystemecosystem
PCBs: Polychlorinated PCBs: Polychlorinated biphenylsbiphenyls
FAT SOLUBLE AND A POP = very stable and resists FAT SOLUBLE AND A POP = very stable and resists degradationdegradation
Used in: power transformers, pesticides, paint, small electric Used in: power transformers, pesticides, paint, small electric parts, etc from 1929 - 1977parts, etc from 1929 - 1977
Enter ecosystem mainly through non-point sourcesEnter ecosystem mainly through non-point sources: products : products with PCBs leak, PCB travels into soil, carried by wind and water with PCBs leak, PCB travels into soil, carried by wind and water into environment (and eventually the ocean)into environment (and eventually the ocean)
In rats – cause liver cancer, pituitary tumors, leukemia, In rats – cause liver cancer, pituitary tumors, leukemia, lymphoma and intestinal cancerlymphoma and intestinal cancer
In humans, classified as a In humans, classified as a probable human carcinogen probable human carcinogen (cancer (cancer causer) causer) →→ banned in 1977 banned in 1977
BioaccumulationBioaccumulation Process by which cells selectively absorb Process by which cells selectively absorb
and store a great variety of moleculesand store a great variety of molecules
Allows cell to accumulate nutrients and Allows cell to accumulate nutrients and essential minerals (like calcium, phosphorus, essential minerals (like calcium, phosphorus, etc.)etc.)
However, same process can also absorb and However, same process can also absorb and store harmful pollutants inside an organismstore harmful pollutants inside an organism• Reason some fish are not fit for human Reason some fish are not fit for human
consumption (usually because of bioaccumulation consumption (usually because of bioaccumulation of mercury)of mercury)
BiomagnificationBiomagnification Process by which the effects of Process by which the effects of
pollutants are pollutants are magnifiedmagnified up an up an ecosystem through food chainsecosystem through food chains When organism consumed by a When organism consumed by a
higher trophic level, only about higher trophic level, only about 10% of energy moves up, however 10% of energy moves up, however majority of the pollutant is passed majority of the pollutant is passed on from prey to consumeron from prey to consumer
Therefore – as the pollutant moves Therefore – as the pollutant moves up the food chain, the up the food chain, the concentration of the pollutant in the concentration of the pollutant in the body tissue increases dramaticallybody tissue increases dramatically
This is especially true for POPs This is especially true for POPs since they persist for long periods since they persist for long periods of timeof time
Biomagnification ExampleBiomagnification ExampleDDT residues - Long Island EstuaryDDT residues - Long Island Estuary
Woodwell, Wurster, Isaacson, 1967Woodwell, Wurster, Isaacson, 1967
Trophic levelTrophic level OrganismOrganism DDT (wet weight)DDT (wet weight)
PrimaryPrimary
ProducerProducer
Green algaGreen alga 0.08 ppm (parts 0.08 ppm (parts per million)per million)
PrimaryPrimary
ConsumerConsumer
Mud snailMud snail 0.26 ppm0.26 ppm
Secondary Secondary
ConsumerConsumer
Summer Summer FlounderFlounder
1.28 ppm1.28 ppm
TertiaryTertiary
ConsumerConsumer
Ring-billed Ring-billed gullgull
75.5 ppm75.5 ppm
Puget sound orcas affected by PCB’sPuget sound orcas affected by PCB’s
Our orcas have, on average, the Our orcas have, on average, the highest highest measured levels of PCB’s measured levels of PCB’s of any marine of any marine mammal IN THE WORLDmammal IN THE WORLD
Almost 150 ppm (parts per million) averageAlmost 150 ppm (parts per million) average >10 ppm PCB known to cause immune problems >10 ppm PCB known to cause immune problems
in sealsin seals Mother can pass as much as 90% of PCB’s to Mother can pass as much as 90% of PCB’s to
her offspring via milk and through placentaher offspring via milk and through placenta Female transient orca found dead on Dungeness Female transient orca found dead on Dungeness
spit in 2002 had 1000 ppm spit in 2002 had 1000 ppm
Yeah, but PCB’s are are banned, right?Yeah, but PCB’s are are banned, right? Double whammy for our orcasDouble whammy for our orcas
Note: PCB’s are less harmful when stored in fat vs. released Note: PCB’s are less harmful when stored in fat vs. released into an Orca’s bloodstream.into an Orca’s bloodstream.
Less food (salmon) so orcas use blubber (fat) for energy Less food (salmon) so orcas use blubber (fat) for energy
↓↓ PCB’s released into bloodPCB’s released into blood
↓↓PCBs interfere with normal immune PCBs interfere with normal immune
functionfunction↓↓
Result: orcas more susceptible to disease + pathogensResult: orcas more susceptible to disease + pathogens
New era, new threatsNew era, new threats
Many countries still use chemicals that Many countries still use chemicals that have proven to bioaccumulatehave proven to bioaccumulate
Chemicals are stored all over the world Chemicals are stored all over the world and are often not properly disposed ofand are often not properly disposed of
US does not have a law that insists on US does not have a law that insists on testing of new chemicals (unless they are testing of new chemicals (unless they are used in food)used in food) Only 10% of the 85,000 chemicals used in Only 10% of the 85,000 chemicals used in
North America have been tested for North America have been tested for environmental effects. environmental effects.
PBDEs: example of a new threatPBDEs: example of a new threat
Polybrominated diphenyl ethersPolybrominated diphenyl ethers Group of fire-retardant chemicals (they Group of fire-retardant chemicals (they
don’t catch fire)don’t catch fire) A POP: structurally similar to PCB’sA POP: structurally similar to PCB’s Found in furniture, televisions, Found in furniture, televisions,
computerscomputers Europe has banned PBDE’s, only state Europe has banned PBDE’s, only state
to ban is Californiato ban is California There IS an available fire retardant There IS an available fire retardant
shown not to bioaccumulateshown not to bioaccumulate
Now complete Analysis Questions 1-5 in your Orcas booklet. Use complete sentences.
Extra creditExtra credit Research report on:Research report on:
PBDE’s or another currently used pollutantPBDE’s or another currently used pollutant Use at least 3 different sources (and provide bibliography)Use at least 3 different sources (and provide bibliography) Include:Include:
• Chemical structureChemical structure• What it is used in/ for (pros)What it is used in/ for (pros)• Environmental/ health impacts (cons)Environmental/ health impacts (cons)• Statement on whether you believe it should continue to be used or outlawedStatement on whether you believe it should continue to be used or outlawed
Now complete the Analysis Questions on pages 5-8 in your Orcas booklet. Use complete sentences.