Black Scoter

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Black Scoter
Adult male
Conservation status
Least Concern
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Aves Order: Anseriformes Family: Anatidae Genus: Melanitta Species: M. americana
Binomial name
Melanitta americana (Swainson, 1832)
Synonyms
Melanitta nigra americana

The Black or American Scoter (Melanitta americana) is a large sea duck, 43 to 49 centimters in length^[1], which breeds over the far north of North America in Alaska, Labrador and Newfoundland, and on Siberia east of the Yana River. Together with the Common Scoter M. nigra, it forms the subgenus Oidemia; the two are sometimes considered conspecific, Black Scoter then being referred to as M. nigra americana.

It winters further south in temperate zones, on the coasts of the northern USA, Canada, and Asia as far south as China. It forms large flocks on suitable coastal waters. These are tightly packed, and the birds tend to take off together. Some birds may over-winter on the Great Lakes. This species is a very rare vagrant to western Europe; only drakes are safely identifiable out of range, so females are likely to be undetected.

The lined nest is built on the ground close to the sea, lakes or rivers, in woodland or tundra. 5-7 eggs are laid. Each eggs weighs from 60-74 grams (2-2.6 oz), or 8% of the females body weight. The incubation period may range from 27 to 31 days. Females brood their young extensively for about 3 weeks, after which the still flightless young must fend for themselves.

The adult female averages about 980 grams (2.1 lbs.) and 45 cm (18 inches) in length, while the adult male is on average 1100 grams (2.4 lbs.) and 49 cm (19 inches) in length. It is characterised by its bulky shape and large bill. The male is all black with a very bulbous bill which is mostly yellow. The female is a brown bird with pale cheeks, very similar to female Common Scoter. This is America's only black duck, although the female may have some yellow around the nostils. When this bird is in flight, there is a silvery appearance from the underside. ^[2]

This species can be distinguished from other scoters, apart from Common, by the lack of white anywhere on the drake, and the more extensive pale areas on the female.

This species dives for crustaceans and molluscs while migrating or wintering on the sea-coasts, and feeds on insects and their larvae, especially caddisflies, fish eggs and, more rarely, vegetation such as duck weed while nesting on freshwater. It has been suggested that in coastal waters this species prefers sheltered enbayments, and possibly waters that include some mixed depths.^[3]

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