Dark-bellied Brent Geese
The Brent Goose belongs to the Branta genus of black geese, which contains species with largely black plumage, distinguishing them from the Anser genus of grey geese.
Branta is a Latinised form of Old Norse brandgás, meaning "burnt (black) goose", and bernicla is the medieval Latin name for the barnacle. The Brent Goose and the similar Barnacle Goose were previously considered a single species and formerly believed to be the same creature as the crustacean, a myth that can be dated back to at least the 12th century.
The Brent Goose, Branta bernicla is divided into 3 sub-species: Dark-bellied Brent Goose B. b. bernicla, Pale-bellied Brent Goose B. b. hrota (sometimes also known as Light-bellied Brent Goose) and Black Brant B. b. nigricans. Some DNA evidence suggests that these forms are genetically distinct and a split into 3 separate species has been proposed. However, other evidence upholds their maintenance as a single species.
The Brent Goose is a small goose, 22 to 26 inches long with a wingspan of 42 to 48 inches. The under-tail is pure white and the tail black and very short (the shortest of any goose).
The Dark-bellied Brent Goose is fairly uniformly dark grey-brown all over and the flanks and belly are not significantly paler than the back. The head and neck are black with a small white patch on either side of the neck. It breeds on the Arctic coasts of central and west Siberia and winters in west Europe with over half the population in south England and the rest between north Germany and north west France.
The Pale-bellied Brent Goose appears blackish-brown and light grey in colour and the flanks and belly are significantly paler than the back and present a marked contrast. The head and neck are black with a small white patch on either side of the neck. It breeds in Franz Josef Land, Svalbard, Greenland and north east Canada and winters in Denmark, north east England, Ireland and the Atlantic coast of the USA from Maine to Georgia as well as in a small but significant area in north France.
The Black Brant appears blackish-brown and white in colour. This sub-species is very contrastingly black and white with a uniformly dark sooty-brown back, similarly-coloured underparts (with the dark colour extending furthest back of the 3 sub-species) and a prominent white flank patch. It also has a larger white neck patch which forms an almost complete collar. It breeds in north west Canada, Alaska and east Siberia and winters mostly on the west coast of north America from south Alaska to California but also in east Asia, mainly Japan. It sometimes appears as a vagrant in Europe when it associates with the other Brent Goose species.
The Brent Goose used to be a strictly coastal bird in winter, seldom leaving tidal estuaries where it feeds on eel-grass and seaweed. In recent decades, it has started using agricultural land a short distance inland, feeding extensively on grass and winter-sown cereals. This may be behaviour learned by following other species of geese. Food resource pressure may also be important in forcing this change since the world population increased over 10-fold by the mid-1980s, possibly reaching the carrying capacity of the estuaries.
In the breeding season, the Brent Goose uses low-lying wet coastal tundra for both breeding and feeding. The nest is bowl-shaped, lined with grass and down and located in an elevated position often near a small pond.
The Brent Goose is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds applies.
Date: 26th December 2011
Location: Salthouse, Norfolk
Branta is a Latinised form of Old Norse brandgás, meaning "burnt (black) goose", and bernicla is the medieval Latin name for the barnacle. The Brent Goose and the similar Barnacle Goose were previously considered a single species and formerly believed to be the same creature as the crustacean, a myth that can be dated back to at least the 12th century.
The Brent Goose, Branta bernicla is divided into 3 sub-species: Dark-bellied Brent Goose B. b. bernicla, Pale-bellied Brent Goose B. b. hrota (sometimes also known as Light-bellied Brent Goose) and Black Brant B. b. nigricans. Some DNA evidence suggests that these forms are genetically distinct and a split into 3 separate species has been proposed. However, other evidence upholds their maintenance as a single species.
The Brent Goose is a small goose, 22 to 26 inches long with a wingspan of 42 to 48 inches. The under-tail is pure white and the tail black and very short (the shortest of any goose).
The Dark-bellied Brent Goose is fairly uniformly dark grey-brown all over and the flanks and belly are not significantly paler than the back. The head and neck are black with a small white patch on either side of the neck. It breeds on the Arctic coasts of central and west Siberia and winters in west Europe with over half the population in south England and the rest between north Germany and north west France.
The Pale-bellied Brent Goose appears blackish-brown and light grey in colour and the flanks and belly are significantly paler than the back and present a marked contrast. The head and neck are black with a small white patch on either side of the neck. It breeds in Franz Josef Land, Svalbard, Greenland and north east Canada and winters in Denmark, north east England, Ireland and the Atlantic coast of the USA from Maine to Georgia as well as in a small but significant area in north France.
The Black Brant appears blackish-brown and white in colour. This sub-species is very contrastingly black and white with a uniformly dark sooty-brown back, similarly-coloured underparts (with the dark colour extending furthest back of the 3 sub-species) and a prominent white flank patch. It also has a larger white neck patch which forms an almost complete collar. It breeds in north west Canada, Alaska and east Siberia and winters mostly on the west coast of north America from south Alaska to California but also in east Asia, mainly Japan. It sometimes appears as a vagrant in Europe when it associates with the other Brent Goose species.
The Brent Goose used to be a strictly coastal bird in winter, seldom leaving tidal estuaries where it feeds on eel-grass and seaweed. In recent decades, it has started using agricultural land a short distance inland, feeding extensively on grass and winter-sown cereals. This may be behaviour learned by following other species of geese. Food resource pressure may also be important in forcing this change since the world population increased over 10-fold by the mid-1980s, possibly reaching the carrying capacity of the estuaries.
In the breeding season, the Brent Goose uses low-lying wet coastal tundra for both breeding and feeding. The nest is bowl-shaped, lined with grass and down and located in an elevated position often near a small pond.
The Brent Goose is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds applies.
Date: 26th December 2011
Location: Salthouse, Norfolk
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Also in: Black geese
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