Common Scoter (Melanitta nigra)

[order] ANSERIFORMES | [family] Anatidae | [latin] Melanitta nigra | [authority] Linnaeus, 1758 | [UK] Common Scoter | [FR] Macreuse noire | [DE] Trauerente | [ES] Negron comun | [NL] Zwarte Zeeeend

Subspecies

Genus

Physical charateristics

Black Scoters are large, mostly black or dark gray sea ducks. Formerly called the Common Scoter, the Black Scoter is the least common of the three scoters. Adult males are solid black with a bulbous yellow knob on an otherwise black bill. Females and juveniles are dark gray, lighter on the cheek with a dark cap. Their bills are dark and lack the knob found in adult males.
Scoters spend the non-breeding part of the year in large flocks on the ocean. Black Scoters forage by diving and swimming under water, propelled by their feet. They usually feed in areas of open water, avoiding dense submergent or emergent vegetation. They swallow their prey under water, unless it is large or bulky. They are strong fliers, but must get a running start on the water to get airborne.

Range

Eurasia : North

Habitat

The breeding range of the Black Scoter is at the edge of the northern forest or in the treeless tundra, where they breed on small, shallow lakes, ponds, sloughs, and river banks with tall grasses to conceal nests. In winter, they can be found on coastal bays and along coastlines, usually in shallow water within a mile of shore

Reproduction

Most females probably start breeding at the age of two. Pairs form in late fall and winter. The female builds the nest on the ground, usually near the water on a hummock or ridge, well concealed by vegetation. The nest is a shallow depression lined with plant material and down. The female lays 8 to 9 eggs and incubates them for 27 to 31 days. The pair bond dissolves, and the male departs for the molting grounds soon after the female begins incubation. It is not known whether pairs re-form in the fall, or if new pairs are formed. Shortly after hatching, the young leave the nest and head to the water. The female tends the young and continues to brood them at night, but they can swim and feed themselves. Most females abandon their broods after one to three weeks. Multiple broods gather together on lakes until they can fly, at 6 to 7 weeks.

Feeding habits

At sea, mollusks are the most common prey item of the Black Scoter, although crustaceans and other aquatic invertebrates are also part of the diet. On fresh water, aquatic insects, fish eggs, mollusks, small fish, and some plant matter are eaten.

Video Common Scoter

httpv://www.youtube.com/watch?v=sOnMqDWjTY4

copyright: youtube

Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Melanitta nigra breeds in northern Europe, which accounts for less than a quarter of its global breeding range. Its European breeding population is relatively large (>100,000 pairs), and was stable between 1970-1990. Populations in most countries-
including the Russian stronghold-were stable during 1990-2000, and thus the species remained stable overall.
Outside the breeding season this duck is almost exclusively a marine species. It breeds in the arctic and boreal regions of a major part of Europe and North America. The western Eurasian population is wintering in the Baltic Sea and along the Atlantic coasts, southwards to North Africa. It is estimated at 1600000 individuals, and seems stable despite some northward contraction of its breeding area. The only breeding population of the European Union is this of the British Isles, currently estimated at 190 breeding pairs.

Migration

Migratory, though some small populations may not move far. Icelandic breeders winter around Ireland, Britain, and Atlantic coasts France, Spain, and Portugal. Movement by small British and Irish population largely unknown, but breeding lakes deserted. Birds wintering Norwegian coast presumably mainly local breeders. Breeders from arctic Russia, east to about Lena river, migrate west to WSW along arctic Ocean to White Sea and overland across north Russia, to winter in Baltic, on both sides of North Sea, west coasts of Britain, France, and north and west Iberia. These wintering areas also used by breeders of Sweden and Finland. Common migrant, of uncertain origin, Atlantic coast Morocco late September to early November.
Peak autumn migration (after moult completed) early November in Baltic, and November to early December in North Sea. Proportions of females and juveniles in western seaboard flocks rise steadily until passage ends December. Icelandic breeders emigrate early September to early October. Return movements late February to April in Atlantic and North Sea, April-May Baltic, and northern breeding grounds re-occupied mid-May to early June.

Distribution map

Literature

Title Distribution and behaviour of Common Scoter Melanitta nigra relative to prey resources and environmental parameters

Author(s): M. J. KAISER, M. GALANIDI et al.

Abstract: Offshore wind farms are proposed around the coast ..[more]..

Source: Ibis 148 (s1), 110-128