Melanitta nigra
The Common Scoter is a highly gregarious bird except when nesting. It is the only breeding species of duck in the UK to be ‘red-listed’ - officially classed as threatened as breeding numbers have suffered a 50% decline over the last 25 years.
Outside the breeding season, large flocks of several thousand birds can often be seen at sea.
Appearance
The bright yellow splash on the bill offers a contrast from the plump jet black bodies of the males.
Location
The Common Scoter breeds in Iceland, Ireland, Scotland, northern Europe and northern Russia; from Norway, east to the Lena River in north eastern Siberia. It winters chiefly on coasts of western Europe (including Britain). Mediterranean, Black and Caspian Seas.
Threats
Eutrophication and afforestation of breeding sites, fish stocking leading to increased competition with scoters for invertebrate food, and predation by introduced mink. Wintering populations are threatened by oil pollution and over-harvesting of shellfish.
Habitat
Nest sites usually occupy tundra vegetation or low heathland, but are always sheltered by tall or overhanging shrubs and often, though not always, near water. Out of the breeding season, the males undergo a moult migration to sea where huge, dense flocks collect together. These flocks then rest and feed in shallow, inshore waters where a depth of not more than 20 metres enables them to dive for an abundant source of shellfish, especially cockles and mussels.
Voice
Females utter a harsh “kr-r-r” call, whilst males have a haunting flute-like piping call mainly during courtship.
Population Dynamics
Scoters are long-lived ducks with generally low annual productivity. Birds may live on average ten years but produce only two young each year. Females nevertheless invest heavily in clutch production, producing on average 6-8 large eggs. Unfortunately females subsequently suffer high mortality because of this investment and Scoter population sex ratios are highly skewed towards males which may outnumber females on wintering sites by four to one.
See them at a WWT centre
Arundel