Post on 27-Mar-2018
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!