加拿大雁
The black head and neck with white "chinstrap" distinguish this goose from all other geese 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. The female looks virtually identical but is slightly lighter and has a different voice. Some are hard to distinguish from the Canada goose, with which the cackling goose was long assumed to form one species, the cackling goose and the smaller Canada goose subspecies being called the lesser Canada goose. The smallest Cackling geese ("B. h. minima") are much smaller than any Canada goose, but the subspecies "B. h. hutchinsii", at up to , 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.