THE WORLD BIRDS - An Online Bird Book
WATERFOWL - Sea Ducks
The term waterfowl is used to describe any member of the order Anseriformes. A series of articles describes all the waterfowl. This specific article describes the
"sea ducks " which belong to family Anatidae, subfamily Merginae.
Anseriformes
Most species of the order Anseriformes spend a considerable amount of time in water. In fact, they are called waterfowls. Their webbed feet make for efficient swimming. A few species spend little time in water and thus their feet are only partially webbed. Most waterfowl are also good flyers, many migrating long distances to escape the cold and others migrating shorter distances for optimizing their food supply. All species, except the screamers, have a wide and relatively flat bill. The shape of a species bill and also their tongue is a function of their diet. Considering the entire order, they eat aquatic plants, grasses, sedges, algae, plankton, insects, insect larvae, mollusks, crustaceans, fish, fruits, grains, rice. Most species are monogamous and if they lose a partner seem to mourn. Males are larger and heavier than females. The chicks are well developed when they hatch and can walk almost immediately.
The order
Anseriformes has 3 familes: Anatidae, Anhimidae, Anseranatidae. Family Anatidae is comprised of the ducks, swans, and geese which amounts to about 160 species. Family
Anhimidae is made up of 3 screamer species while family
Anseranatidae has only one species, the magpie goose. Since these latter two families contain so few species, it seems appropriate to consider the entire order in this series of articles.
Anatidae
The Anatidae family has the following subfamiles:
Anatinae: dabbling ducks and
teals
Anserinae: geese, swans
Aythyinae: diving ducks
Dendrocygninae: whistling ducks
Merginae: sea ducks
Oxyurinae: stiff-tailed ducks
Plectropterinae: spur-winged goose
Stictonettinae: freckled duck
Tadorninae: shelducks, shelgeese
Sea Ducks
Most
sea ducks are essentially marine outside the breeding season, hence their name. Many species have developed specialized salt glands to allow them to drink salt water. But often the young cannot process salt water which helps explain why sea duck breeding sites are near freshwater. These breeding sites are in northern latitudes near ponds and lakes.
There are 4 main groups of sea ducks: the goldeneyes and the bufflehead, the scoters, the mergansers, and the eiders. The 2 goldeneye species are similar in looks and quite small, about 500 gm. The bufflehead is twice as big, about 1000 grams. They all forage by diving.
There are 6 scoter species in genus
Melanitta. They are fairly large sea ducks, the males reach about 1000 gm and the females a little smaller. Male scoters are mostly black with swollen bills; females mostly brown. They breed in northern latitudes, often in taiga or tundra habitats near freshwater. The winter more south to temperate climates usually along the coast. Scoter generally dive for their food, using feet and wings for propulsion. They eat crustaceans, mollusks, fish, aquatic insects and also some aquatic vegetation.
The mergansers are comprised of the "true" mergansers of genus
Mergus, the smew (
Mergellus albellus) and the hooded merganser (
Lophodytes cucullatus). They vary greatly in size with the smew under 700 gms and the common merganser reaching 2000 gms. These "sea ducks" mainly eat fish. To help them grasp their prey, they have serrated edges on their long and thin bills. They capture fish by diving and chasing them under water. Even though they are in the sea duck subfamily Merginae, only the red-breasted merganser spends much time in the sea; the others almost exclusively find their fish in fresh waters.
Eiders breed in the cooler latitudes of the Northern hemisphere. They are famous for their "eiderdown" which is a great insulator and thus makes light and very warm feeling comforters. Except for Steller's eider which does not reach a kg, there are large birds with the male common eider averaging over 2000 gm and some reaching 3000 gm.
Common Merganser Image by
Quartl
Genus Bucephala
The genus contains the bufflehead and the two goldeneye species. They all forage by diving and spend the breeding season at northern latitudes near freshwaters. The goldeneyes migrate slightly south, but the bufflehead goes considerable south, some to Mexico. They eat crustaceans, mollusks, insects, aquatic vegetation.
Bufflehead Bucephala albeola
Image by: 1) Alan_D_Wilson - California
2, 3
) Dick Daniels -
Sylvan
4) Roy McBride - Vancouver, BC
1, 2) Female 3, 4) Male
Goldeneye, Barrow's Bucephala islandica
Image by: 1)
Donna Dewhurst, USFWS 2, 3, 4) Dick Daniels -
Sylvan Heights
1, 2) Female 3, 4) Male
Goldeneye, Common Bucephala clangula
Image by: 1)
Peggy 2,
3, 4) Dick Daniels -
Sylvan Heights
1, 2) Female 3, 4) Male
Genus Clangula - 1 species
Duck, Long-tailed Clangula hyemalis
Image by: 1) Alan_D_Wilson 2)
Dick Daniels - Alaska Sea Life Center, Seward Alaska 3)
Wolfgang_Wander 4)
Nasser_Halaweh
1) winter female 2) summer female 3) winter male 4) summer male
Genus Histrionicus - 1 species
Duck, Harlequin Histrionicus histrionicus
Image by: 1, 2) Alan D Wilson - British Columbia 3, 4) Dick Daniels-
Sylvan Heights
1, 2) Female 3. 4) Male
Genus Melanitta
The male scoters are mostly black with swollen bills; females mostly brown. They breed in northern latitudes, often in taiga or tundra habitats near freshwater. They winter more south to temperate climates usually along the coast. Scoters generally dive for their food, using feet and wings for propulsion. They eat crustaceans, mollusks, fish, aquatic insects and also some aquatic vegetation.
Scoter,_Black Melanitta americana
Image by: 1)
Jonathan_Coffin 2)
Tom_Benson 3)
Peter Massas 4) Andrew Reding - Washington
1, 2) Female 3) Juvenile male 4) Male
Scoter,_Common Melanitta nigra
Image by: 1)
JV Verde - Portugal 2)
Stefan Bemdtsson 3)
Mike_Prince 4)
Jason Thompson - West Sussex
1, 2) Female 3, 4, 5) Male
z
Scoter,_Stejneger's Melanitta deglandi
Scoter,_Surf Melanitta perspicillata
Image by: 1, 2) Alan D Wilson Huntington Beach, California 3)
Mike Baird - CA, 4) Dick Daniels - Cape May, New Jersey ferry
1) Female 2 - 4) Male
Scoter,_Velvet Melanitta fusca
Image by: 1)
D_Gordon_Robertson - Scotland 2)
Frank_Vassen - Belgium
Scoter,_White-winged Melanitta deglandi
Image by: 1)
USFWS 2) Elaine
R Wilson - British Columbia 3) Alan D. Wilson - British Columbia 4) Andrew_Reding
1) Female 2, 3, 4) Male
Mergansers
The mergansers are comprised of the "true" mergansers of genus
Mergus, the smew (
Mergellus albellus) and the hooded merganser (
Lophodytes cucullatus). These "sea ducks" mainly eat fish. To help them grasp their prey, they have serrated edges on their long and thin bills. They capture fish by diving and chasing them under water. Even though they are in the sea duck subfamily Merginae, only the red-breasted merganser spends much time in the sea; the others almost exclusively find their fish in fresh waters.
All except the Brazilian merganser are restricted to the Northern Hemisphere. Of these northern species, all spend the breeding season way north - many in tundra and taiga regions. Even in the winter, they do not travel to real warm climates; their main concern is that ice does not prevent them from finding fish. Except for one exception, which is again the Brazilian merganser, all females have similar looking heads - reddish-brown with a long and thin bill. The female Brazilian has a black head. And except for the smew, all male mergansers have a black head, again with a long thin bill.
Genus Lophodytes - 1 species
Merganser,_Hooded Lophodytes cucullatus
Image by: 1)
BS_Thurner_Hof 2, 3, 4) Dick Daniels
1, 2) Female 3, 4) Breeding male
Genus Mergellus - 1 species
Smew Mergellus albellus
Image by:
1, 2, 3, 4)
- Dick Daniels -
Sylvan Heights
1, 2) Female 3, 4) Male
Genus Mergus
Most of these "sea ducks" actually prefer rivers, streams, and also lakes. The red-breasted merganser is an exception and in the winter season it prefers coastal waters. These
Mergus mergansers have long thin bills with serrated edges which helps to firmly hold fish which is their primary food. They may first put their head under water to spot a fish and then dive to pursue it. They often go upstream as they are hunting so that the water where they are hunting remains clear and undisturbed.
Merganser,_Brazilian Mergus octosetaceus
Image by: 1) Nick Athanas - Brazil 2)
Claudio Timm 3)
Savio Bruno - Brazil
1) Pair, male on left 2) Female 3) Male
Merganser,_Common Mergus merganser
Image by:
1, 3) Dick -
Sylvan Heights 2) Ted
Grussing -
Arizona 4)
Tony_Hisgett - England
1, 2) Female 3, 4) Male
Merganser,_Red-breasted Mergus serrator
Image by: 1)
Phil_Graham 2) Alan D Wilson - California 3) peggycadigan 4)
Ingrid Taylor -
Marganser,_Scaly-sided Mergus squamatus
Image by: 1)
Dick Daniels -
Sylvan Heights 2, 3) BS Thurner Hof 4)
Massimiliano_Sticca
1) Pair 2) Female 3, 4) Male
Eiders
Eiders are large
sea ducks. They breed in the cooler latitudes of the Northern hemisphere. They are famous for their eiderdown which is a great insulator and thus makes light and very warm feeling comforters. The female common eider plucks the down from her breast to line the nest. The resulting nest is thus soft and warm. After the eiders vacate the nest, people harverst the eider so this is a very ecofriendly material - no birds need be killed when it is commercially obtained. Of course, not only does eiderdown help the young with their comfortable nest, it also provides the adults with great insulation. These warm eiders are able to stay in harsh winter climates as long as there is open water for swimming. In addition to eiderdown, some geese and ducks have been domesticated because they also have down with good insulating properties, but not as good as the eider's.
Genus Polysticta - 1 species
Eider, Steller's Polysticta stelleri
Image by:
1) Laura Whitehouse 2)
Glen Smart, USFWS
3, 4) Ron_Knight
1, 2) Female 3, 4) Male
Genus Somateria
These eiders all breed in the cooler latitudes of the Northern Hemisphere.
Eider, Common Somateria mollissima
Image: 1)
Amanda Boyd, USFWS 2) Dick Daniels -
Sylvan Heights 3 Dick - Scotland 4)
Steve Garvie - Scotland
1, 2) Female 3, 4) Male
Eider, King Somateria spectabilis
Image by:
1)
Ómar Runólfsson - Iceland
2, 3) Dick Daniels - Alaska Sea Life Center in Seward
4) Ron_Knight
1) Breeding female 2) Nonbreeding female 3) Nonbreeding male 4) Breeding male
Eider, Spectacled Somateria fischeri
Image by:
1, 2 Dick Daniels -
Sylvan Heights 3, 4) Laura Whitehouse
1, 2) Female 3, 4) Breeding male