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 –

Subfamily Dendrocygninae – Subfamily Anserinae – Subfamily Anatinae -

Handout

• Indicates those species occurring regularly in ID

Ducks =

Geese =

Swans =

What separates the 3 groups?

Ducks -

Geese -

Swan -

What separates the 3 groups?

Ducks –

Geese –

Swan –

Non-waterfowl

Cranes, rails – Coots – Grebes – Loons – Woodcock and snipe –

These are not on handout but are managed by USFWS as are waterfowl

On handout:

Subfamily Dendrocygninae –

Occur along gulf coast and Florida

On handout:

Subfamily Anserinae – geese and swansTribe Cygnini –

Tribe Anserini –

On handout:

Subfamily Anatinae – ducks, with 4 tribes

Tribe Anatini –

Tribe Aythyini –

Tribe Mergini –

Tribe Oxyurini –

Swans - Cygnini

Trumpeter swan and tundra swan

Monogamous:

Territory for nesting:

Feed:

Swans:

Largest waterfowl but how much do they weigh?

Tundra swan – Trumpeter swan –

Long-lived species – sexually mature at:Tundra –

Trumpeter –

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 – 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?

Geese - Tribe Anserini

All show several similarities:

Geese - Anserini

Migratory:

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

Winter behavior:

Canada Goose – Branta canadensis

11 subspecies – large or small, dark These 5 are small and light

B.c. leucopareia Aleutian 4 lbs smallB.c. minima Cackling 2.8-3.4 smallB.c. hutchinsii Richardson’s 4 smallB.c. taverneri Taverner’s 4.7-5.9 smallB.c. parvipes Lesser 5-6 small

Large subspecies

B.c. canadensis Atlantic 6.8-8.8B.c. interior Todd’s 7-9B.c. occidentalisDusky 8-9 darkB.c. fulva Vancouver 8-9 darkB.c. moffitti Western 8-10B.c. maxima Giant 11-12

Why are these subspecies important?

Canada Goose - Ecology

Monogamous:

Breeding:

Mortality:

Grazing:

Canada goose (cont.)

Pairing:Territorial:Nesting:Predators of eggs:Incubation:Renesting:Goslings:

Subfamily Anatinae – Ducks

Tribe Anatini –

Only 2 genera in North America

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

Dabblers OthersLegs:Feed:Hind toe:Foot:Speculum:Tail:Take off:

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 –

Anas

Highly social:All migratory:Winter:Forage:Nest:Pairs:

Anas (cont.)

All incubate 21-27 days, young fly at 38-70 daysTeal, green and blue-winged lay 8-11 eggsCinnamon 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 foodNest:Sex ratios:Mating system:Male Parental Care:

Aythya

Divide water area by depths and foodsRedhead 3-4 feet, eats more plantsCanvasback 3-6 feet, eats plants, inverts

Aythya

Divide water area by depths and foodsRedhead 3-4 feet, eats more plantsCanvasback 3-6 feet, eats plants, invertsRing-necked duck <6 ft, eats more snails, invertsGreater scaup 6-15 ft, eats clams, often marineLesser 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 –Divers -

Redhead is a brood parasite

Female uses one of three strategies:

Tribe Mergini – sea ducks

Eiders, mergansers, scoters, goldeneyes, harlequin duck, long-tailed duck, bufflehead

Mergini (cont.) Eiders

Eiders are marine ducks of the arctic, rarely reaching coasts of lower 48 states except

common eider on Atlantic coast to NJking eider to WA and OR

Mergini (cont.) Scoters

Scoters – pelagic, Atlantic and Pacific populationsblack scoter, surf scoter, white-winged scoter

Eat mollusks, crustaceans, inverts, some seeds

Lay 5-9 eggs, broods fly at 50-75 days, form creches

Mergini (cont.) Mergansers

Sawbills, eat fish, sex ratio favors males (64-67%)breed at 2 years

Hooded merganser – nests in cavitiesRed-breasted merganser – nests on ground,

sometimes in burrows, or tree cavitiesCommon merganser – nests in cavities, ground,

will sometimes scavenge dead fish

Mergini (cont.) - Goldeneyes

Common and Barrow’s Goldeneye, Bufflehead all genus Bucephala

All breed at 2 years, nest in cavities, eat inverts and mollusks

Mergini (cont.) - Long-tailed duck

Only member of genus Clangula in worldDeepest diving duck – over 200 feetFormerly called oldsquawEats inverts, crustaceans, mollusks, fishOutside of the breeding season, it is rarely inland,

but stays on coasts

Mergini (cont.) – Harlequin duck

Only member of this genus Histrionicus in world

nests along fast moving streams and rocky coasts

Walks on bottom, eats crustaceans, mollusks, aquatic invertebrates

Tribe Oxyurini – Stiff-tailed Ducks

8 species worldwide, one in NA – ruddy ducklong, 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!