Friday, January 27, 2012

Brant

Brants are fascinating. These small geese breed across the world's Arctic areas. Two races are found in North America, the Light-bellied Brant and the Black Brant. The first photograph (taken at Cape Hatteras, North Carolina) is of the Light-bellied form, which winters along the Atlantic Coast. The second photograph (taken at Morro Bay, California) is of a Black Brant, which winters along the Pacific Coast of California. Where the two races meet in the Arctic, they freely interbreed.

The situation is even more complicated. Brant wintering in Puget Sound look to be intermediate geese, but mainly breed on Melville and St Patrick's islands, and thus may actually be a third North American race (or species) of Brant. These "High-Arctic" Brants differ from known hybrids in genetics, range, and plumage. The story thickens. The first Black Brants were collected in New Jersey, well away from the Pacific winter range. These first specimens may represent a now extinct race of Brant, the Lawrence's Brant, which probably became extinct in the 1930s. Want more? Light-bellied Brant that now winter in New Jersey often have white neck collars that completely circle their necks. They are also genetically distinct from other Brants wintering in New York and Virginia. Are these birds yet another race of Brant? This information comes from Reed et al. (1998).

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