*** Welcome to piglix ***

Seaduck

Sea ducks
Histrionicus histrionicus drake Barnegat.jpg
Harlequin duck, Histrionicus histrionicus (male)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
Subfamily: Merginae
Genera

Chendytes (extinct)
Polysticta
Somateria
Histrionicus
Camptorhynchus (extinct)
Melanitta
Clangula
Bucephala
Mergellus
Lophodytes
Mergus


Chendytes (extinct)
Polysticta
Somateria
Histrionicus
Camptorhynchus (extinct)
Melanitta
Clangula
Bucephala
Mergellus
Lophodytes
Mergus

The seaducks (Merginae) form a subfamily of the Anatidae, which is a group of waterfowl that includes the ducks, geese and swans. Most species within this group spend their winters near coastal marine waters. Many species have developed specialized salt glands to allow them to tolerate salt water, but these are poorly developed in juveniles. Some of the species prefer riverine habitats. All but two of the 20 species in this group occupy habitats in far northern latitudes.

The fish-eating members of this group, such as the mergansers and smew, have serrated edges to their bills to help them grip their prey. These are therefore often known as "sawbills". Other seaducks forage by diving underwater, taking molluscs or crustaceans from the sea floor.

Unlike the Alcidae (auks), the Merginae take on the eclipse plumage during the late summer, and molt into their breeding plumage during the winter.

There are twenty living species in ten extant genera:


...
Wikipedia

...