The Brant, or Brent Goose (Branta bernicla), is a species of goose of the genus Branta. The black brant is a pacific North American subspecies. The brant is a small goose with a short, stubby bill. It measures 22–26 in long, The under-tail is pure white, and the tail black and very short (the shortest of any goose).
The species is divided into three subspecies: Dark-bellied brant B. b. bernicla (Linnaeus, 1758) Pale-bellied brant B. b. hrota (Müller, 1776) (sometimes also known as light-bellied brent goose in Europe, and Atlantic brant in North America) Black brant B. b. nigricans (Lawrence, 1846) (sometimes also known as the Pacific brant in North America)
Some DNA evidence suggests that these forms are genetically distinct; while a split into three separate species has been proposed, it is not widely accepted, with other evidence upholding their maintenance as a single species.
The body of the dark-bellied form is fairly uniformly dark grey-brown all over, the flanks and belly not significantly paler than the back. The head and neck are black, with a small white patch on either side of the neck.