Brant (goose) the "Agreement on the Conservation of African-Eurasian Migratory Waterbirds" applies. "Branta" is a Latinised form of Old Norse "brandgás", "burnt (black) goose", and "bernicla" is the medieval Latin name for the barnacle. The brant and the similar barnacle goose were previously considered one species, formerly believed to be the same creature as the crustacean. That myth can be dated back to at least the 12th century. Gerald of Wales claimed to have seen these birds hanging down from pieces of timber, William Turner accepted the theory, and John Gerard claimed to have seen the birds emerging from their shells. The
Cackling goose populations may still be declining, especially of the subspecies "minima" and "leucopareia". Though the taxonomic distinctness of the Komandorski and Kuril Islands populations, which used to winter in Japan, is controversial, it is without doubt that they disappeared around 1929. The genus name "Branta" is a Latinised form of Old Norse "Brandgás", "burnt (black) goose", and the specific epithet "hutchinsii" commemorates English surgeon Thomas Hutchins who was employed by the Hudson's Bay Company. The cackling goose was originally considered to be the same species or a subspecies of the Canada goose, but in July 2004 the American Ornithologists' Union's (AOU)