Waterfowl What they are and are not - University of Idaho – What they are and are not Great...

Post on 27-Mar-2018

220 views 3 download

Transcript of Waterfowl What they are and are not - University of Idaho – What they are and are not Great...

Waterfowl – What they are and

are not

Great variety in sizes, shapes, colors

All have webbed feet and bills

Sibley reading is great for lots of facts and insights

into the group

Order Anseriformes

Family Anatidae – 154 species worldwide, 44 in NA

Subfamily Dendrocygninae – whistling ducks

Subfamily Anserinae – geese & swans

Subfamily Anatinae - ducks

Handout

• Indicates those species occurring regularly in ID

Ducks = ??

Handout

• Indicates those species occurring regularly in ID

Ducks = 26 species

Geese = ??

Handout

• Indicates those species occurring regularly in ID

Ducks = 26 species

Geese = 6 (3 are rare)

Swans = ??

Handout

• Indicates those species occurring regularly in ID

Ducks = 26 species

Geese = 6

Swans = 2

What separates the 3 groups?

Ducks -

Geese -

Swan -

What separates the 3 groups?

Ducks – smaller, shorter legs & necks

Geese – long legs, graze in uplands

Swan – shorter legs than geese, long necks, larger

size, feed more often in water

Non-waterfowl

Cranes, rails – beak, rails have lobed feet

Coots – bill but lobed feet

Grebes – lobed feet

Loons – webbed feet but sharp beak

Woodcock and snipe – feet not webbed, beaks

These are not on handout but are managed by

USFWS as are waterfowl

On handout:

Subfamily Dendrocygninae – whistling ducks – used to be called tree ducks

2 species, more goose-like, longer necks and legs than most ducks, flight is faster than geese, but slower than other ducks

Occur along gulf coast and Florida

On handout:

Subfamily Anserinae – geese and swans

Tribe Cygnini – swans – 2 species

Tribe Anserini – geese – 6 spp that occur in ID;

but Emperor Goose, Ross’ Goose and Brant

are rare - 3 common species are??

On handout:

Subfamily Anatinae – ducks, with 4 tribes

Tribe Anatini – dabbling ducks, 10 species in ID,

wood duck is called a perching duck

On handout:

Subfamily Anatinae – ducks, with 4 tribes

Tribe Anatini – dabbling ducks, 10 species in ID,

wood duck is called a perching duck

Tribe Aythyini – diving ducks, 5 species

On handout:

Subfamily Anatinae – ducks, with 4 tribes

Tribe Anatini – dabbling ducks, 10 species in ID,

wood duck is called a perching duck

Tribe Aythyini – diving ducks, 5 species

Tribe Mergini – sea ducks, 10 species in ID, but

only 6 are common

On handout:

Subfamily Anatinae – ducks, with 4 tribes

Tribe Anatini – dabbling ducks, 10 species in ID,

wood duck is called a perching duck

Tribe Aythyini – diving ducks, 5 species

Tribe Mergini – sea ducks, 10 species in ID, but

only 6 are common

Tribe Oxyurini – stiff-tailed ducks, 1 species

Swans - Cygnini

Trumpeter swan and tundra swan

Sexes look alike

Monogamous, pair bond formed in winter, mate for life; young are called cygnets

Require large territory for nesting – 30-70 hectares

generally on shore or small islands

Feed in water, tip-up, eat plants (pondweeds, milfoils, sedges)

Swans:

Largest waterfowl but how much do they weigh?

Swans:

Largest waterfowl but how much do they weigh?

Tundra swan – 13-16 pounds

Trumpeter - ???

Swans:

Largest waterfowl but how much do they weigh?

Tundra swan – 13-16 pounds

Trumpeter swan – 22-28 pounds

Long-lived species – sexually mature at:

Tundra – 3-4 years, Trumpeter – 4-6 years

Swans:

Both species lay 4-5 eggs, only female incubates,

31-33 days

Very high nest success – 90%

Why is nest success so high?

Swans:

Both species lay 4-5 eggs, only female incubates, 31-33 days

Very high nest success – 90%

Why is nest success so high? – attentive parents, few nest predators

Both parents care for young, still lose 30%-50%+ of young,

long flightless period – 8-10 weeks for Tundra, 13-17 weeks for Trumpeter

Swans – differences between

species:

Voice, yellow spot in front of eye of Tundra sometimes

Tundra – very social outside breeding season – 1000’s, Trumpeter in small groups – 20-50

Hunted? Trumpeter – no, as many as 40,000

Tundra – yes, 200,000+ in breeding population,

hunted in MT, UT, NV, NC, MD

ID and WA projects

Geese - Tribe Anserini

All show several similarities:

Plumage is not sexually dimorphic

Geese - Tribe Anserini

All show several similarities:

Plumage is not sexually dimorphic

Feed by grazing

Geese - Tribe Anserini

All show several similarities:

Plumage is not sexually dimorphic

Feed by grazing

Highly gregarious

Geese - Tribe Anserini

All show several similarities:

Plumage is not sexually dimorphic

Feed by grazing

Highly gregarious

Breed in open situations

Geese - Tribe Anserini

All show several similarities:

Plumage is not sexually dimorphic

Feed by grazing

Highly gregarious

Breed in open situations

Non-breeders form molting flocks in summer,

are joined by breeders a few weeks later

Geese - Anserini

Migratory and some species have a molt migration

Geese - Anserini

Migratory and some species have a molt migration

During fall and winter the family unit stays together and in larger flocks

Winter behavior is to gather in large concentrations in open areas, make morning and evening flights to feed

Canada Goose –Branta canadensis

In 2004 the 11 subspecies of Canada goose were

re-categorized into 2 species:

– Canada Goose – with 7 subspecies (large)

– Cackling Goose – with 4 subspecies (small)

Canada Goose – Branta canadensis

7 subspecies – large bodies, interior

B.c. parvipes Lesser 5-6 pounds

B.c. canadensis Atlantic 6.8-8.8 lbs

B.c. interior Hudson Bay 7-9 lbs

B.c. occidentalis Dusky 8-9 lbs dark

B.c. fulva Vancouver 8-9 lbs dark

B.c. moffitti Great Basin 8-10 lbs

B.c. maxima Giant 11-12 lbs

Cackling Goose – Branta hutchinsii

4 subspecies – all smaller than Canada geese,

breeds more in coastal regions of NW

B.h. minima Cackling 2.8-3.4 lbs

B.h. leucopareia Aleutian 4 lbs

B.h. hutchinsii Richardson’s 4 lbs

B.h. taverneri Taverner’s 4.7-5.9 lbs

– (overlap with Lesser Canada goose)

Why are these subspecies

important?

Several subspecies are uncommon, and management is aimed at them

Subspecies often overlap in breeding and wintering ranges

Geese are managed by populations

Canada Goose - Ecology

Monogamous, highly social,

Begin to breed at 2, most at 3, equal sex ratio

Mortality rates from 25-50% per year depending on

human exploitation

Grazers – especially cereal grains, clovers, alfalfa

therefore lots of management involves planted

foods

Canada goose (cont.)

Pair in winter, for life, migrate N in spring

Territorial – nests elevated, islands, osprey nests

Both parents stay at nest, female inc., 5-6 eggs

Canada goose (cont.)

Pair in winter, for life, migrate N in spring

Territorial – nests elevated, islands, osprey nests

Both parents stay at nest, female inc., 5-6 eggs

Predators on eggs – skunks, foxes, coyotes, ravens,

crows, magpies

Incubation is 25-30 days, nest success = 70%

A small % of females renest (10%) – define?

Goslings fly at 7-10 weeks

Subfamily Anatinae – Ducks

Tribe Anatini – dabbling ducks

Only 2 genera in North America

Aix

Anas

Tribe Anatini - Dabblers

Dabblers all spring up off the water or land to fly

All dabble, or tip up, to feed, but many also feed on

land

Rarely dive but can

Dabblers vs others

Legs near center of body legs back

Tip up dive

Hind toe not lobed hind toe lobed

Dabblers vs others

Legs near center of body legs back

Tip up dive

Hind toe not lobed hind toe lobed

Foot smaller foot larger

Iridescent speculum dull speculum

Tail held clear of water tail in water

Spring up run along surface

Dabblers

Most field guides have the speculum much too

visible for the bird at rest

Most field guides also have divers and sea ducks

sitting too high in the water

Aix sponsa – wood duck

Also called a perching duck – its legs are even

more forward then other dabblers, well adapted

to perching in trees

Sharp claws and well-developed hind toes

Nest in cavities, usually over water, 2-20 m up

Anas

Highly social (1000s), especially in winter

All migratory, some use both fresh and estuarine

wetlands during the year

Often winter in huge mixed species flocks

Anas

Highly social (1000s), especially in winter

All migratory, some use both fresh and estuarine wetlands during the year

Often winter in huge mixed species flocks

Divide up foraging areas by water depth

All nest on the ground, none in cavities

No long-term pair bonds, monogamous until incubation begins, then male leaves

Anas (cont.)

All incubate 21-27 days, young fly at 38-70 days

Teal, green and blue-winged lay 8-11 eggs

Cinnamon teal lays 7-12 eggs

Northern pintail lays 6-9 eggs, often nests far

from water

Mallard lays 7-10 eggs, largest population in NA

Tribe Aythyini – diving ducks or

pochards (5 species):Genus Aythya

All dive for food

Generally nest over water

Sex ratios 60% + males

Monogamous, male defends the female

Tribe Aythyini – diving ducks or

pochards (5 species):Genus Aythya

All dive for food

Generally nest over water

Sex ratios 60% + males

Monogamous, male defends the female

Male leaves during incubation

Many first year females do not breed

7-12 eggs, first flight for young is at 40-68 days

Aythya

Divide water area by depths and foods

Redhead 3-4 feet, eats more plants

Canvasback 3-6 feet, eats plants, inverts

Ring-necked duck <6 ft, eats more snails, inverts

Greater scaup 6-15 ft, eats clams, often marine

Lesser scaup 10-40 ft, eats clams, inverts, snails

Aythya

Brood behavior when threatened:

Divers vs dabblers

Dabblers - ?

Divers -?

Aythya

Brood behavior when threatened:

Divers vs dabblers

Dabblers – seek cover in emergent veg.

Divers -?

Aythya

Brood behavior when threatened:

Divers vs dabblers

Dabblers – seek cover in emergent veg.

Divers – move to open water and may dive

Redhead is a brood parasite

Female uses one of three strategies:

incubates own clutch

incubates own clutch and parasitize other nests

entirely parasitic on canvasback and redhead

Canvasbacks parasitized by redheads generally not as successful in producing their own ducklings

Tribe Mergini – sea ducks

Most species associated with coastal and estuarine

waters, but many found inland on freshwater

lakes and larger rivers

Eiders, mergansers, scoters, goldeneyes,

harlequin duck, long-tailed duck, bufflehead

Tribe Oxyurini – Stiff-tailed Ducks

8 species worldwide, one in NA – ruddy duck

long, stiff tail

Large bills, clumsy on land, nest over water

Very large egg for size of bird, 6-8, will parasitize

each other and redheads

Eat aquatic inverts, snail, plants in winter

The End

Waterfowl are wonderful!