Pacific
Black Brant
(Branta
bernicla nigricans)
Black Brant (Branta bernicla) is a small sea goose species that
is circumpolar in its distribution. Black Brant breed in the North American
and Eurasian Arctic.In North America
there are two subspecies: the eastern Branta bernicla hrota, which
winters along the Atlantic Coast from Massachusetts to North Carolina,
and the western Pacific Black Brant (Branta bernicla nigricans),
which primarily winters in Baja California, Mexico.
Between 120,000-140,000 Pacific Black Brant (Branta bernicla nigricans) migrate along the Pacific Flyway each year.They follow a route that goes as far north as Prince Patrick and Mellville Islands in the Canadian North and as far south as Baja California in Mexico. Brant geese form long-term, monogamous pair-bonds and family units migrate together during the year.
Ninety-five per cent of the diet is composed on eelgrass (Zostera marina and Zostera japonica) which grows in the brackish waters of intertidal mudflats.Unlike many other goose species, Brant along the Pacific coastline of British Columbia are strictly coastal. They do not come inland to graze in fields and are not a nuisance to agricultural practices.
Within
the Pacific Brant population there are two distinct genetic stocks: Grey-bellied
Brant (Western High-Arctic Brant) and Black-bellied Brant.Not
yet taxonomically differentiated, these two races are separated genetically
and geographically.Grey-bellied
Brant breed exclusively in the Canadian High Arctic and winter in Padilla
Bay, Washington. Black-bellied Brant have a broader breeding range, the
largest colonies of which are in the Yukon-Kuskokwim Delta in southwestern
Alaska.Ninety-one percent of the
Black-bellied Brant winter in Mexico (that is 80% of the entire Pacific
Brant population) with the remaining birds wintering as small populations
along the Pacific Coast between Alaska and California (Sedinger
et al
1994).