The Cackling Goose (Branta hutchinsii), formerly known as Lesser or Small Canada Goose in North America, belongs to the genus Branta of black geese, which contains species with largely black plumage, distinguishing them from the grey Anser species.
The black head and neck with white "chinstrap" distinguish this goose from all except the larger Canada Goose (Branta canadensis) and the similarly sized Barnacle Goose (B. leucopsis). There are up to 5 subspecies of Cackling Goose, of varying sizes and plumage details. Some are hard to distinguish from the Canada Goose, with which the Cackling Goose was long assumed to form one species, and the name Lesser Canada Goose properly denotes the subspecies parvipes of the Canada Goose. The smallest 1.4 kg-Cackling Geese (B. h. minima) are much smaller than any Canada Goose, but the subspecies B. h. hutchinsii, at up to 3 kg, grows to the same size as some Canada Geese. The distinctness of the extinct population of the Komandorski and Kuril Islands B. h. asiatica is controversial. The Barnacle Goose differs in having a black breast and grey, rather than brownish, body plumage.