Latin: Branta bernicla
Average length: M 25", F 23"
Average weight: M 3.4 lbs., F 3.1 lbs.
Description: In North America, two subspecies are recognized mostly due to differences in plumage characteristics - Atlantic or black (Pacific) and are separated into subpopulations inhabiting distinct ranges and having genetic variation. Brant are small, dark geese that have large wings, which give them their characteristic strong flight. They have short necks, small heads and bills. All subspecies have a black head, bill, breast, primaries, tail and legs. The otherwise black neck has a series of white striations, called a necklace, about the middle. The color of the belly varies according to subspecies and subpopulation. Both sexes are identical in plumage except that the males white necklace is larger than the females.
Breeding: Brant often nest in loose colonies in arctic North America and Russia. They breed on the coastal tundra, in low and barren terrain; on islands, deltas, lakes, and sandy areas among puddles and shallows, and in vegetated uplands. They will often build nests on small offshore islands, on islands in small ponds or on gravel spits to avoid predation. Parents are bonded for life and both tend to nests and young. Female brant lay an average of 5 eggs.
Migrating and Wintering: In North America, brant winter along the Pacific coast from Alaska to Baja California and mainland Mexico and along the Atlantic coast from Massachusetts to North Carolina (mainly from New Jersey to North Carolina). Since the mid-1960s, more than 80% of the counted winter population from Russia, Japan and North America has occurred in Baja California and other parts of northwest Mexico. Brant winter primarily in marine habitats that are marshy, along lagoons and estuaries, and on shallow bays. Habitat use is often limited by the availability of eelgrass, a staple of the diet.
Population: Currently there are two populations of brant recognized in North America, Pacific and Atlantic. The Pacific or black brant have exhibited a significant downward trend from 1964 to 1992 and appear to be below historic population levels. The January 2000 survey in the Pacific Flyway resulted in a count of 135,000 birds, which is 5% higher than the previous year's count. The Atlantic brant population has fluctuated dramatically, but numbers have increased over much of its range. The January 2000 estimate of Atlantic brant was 157,200 birds, which is 8% less than last year's estimate, but 11% higher than the 10-year average.
Brant are strongly dependent upon certain foods and thus the population is vulnerable to losses due to starvation and temporary breeding failure.
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