Branta

Branta is a genus of geese in the family Anatidae. Species in this genus are commonly known as dark-bellied geese and are distinguished from other geese in the genus Anser by darker plumage on the head and body, often with contrasting facial markings. The genus includes several living species distributed across the northern hemisphere, notably the Canada goose (Branta canadensis), the barnacle goose (Branta leucopsis), the brent goose (Branta bernicla), the red-breasted goose (Branta ruficollis), and the Hawaiian goose (Branta sandvicensis).

Other forms within Branta include the cackling goose (Branta hutchinsii), which some classifications treat as a separate species while others regard as a subspecies of the Canada goose; taxonomy varies among authorities. Subspecies within Branta bernicla, such as the black brant (B. b. nigricans), illustrate the complexity of recognition within the genus.

Branta geese typically breed in Arctic and subarctic regions and migrate to temperate zones in North America, Europe, and Asia for the winter. They are primarily herbivorous, feeding on grasses, sedges, and aquatic plants, and they may graze in agricultural fields during migration and winter. Nesting occurs on the ground near water; clutches commonly contain about 3 to 6 eggs, incubated by both parents for roughly 25 to 30 days. Goslings are precocial and relatively self-sufficient soon after hatching.

Conservation status varies by species. Many Branta geese have stable populations, but some have faced declines and are considered threatened or endangered in certain regions, including some Arctic-nesting forms and the Hawaiian goose at various times. The genus is of interest for studies of migration, population dynamics, and habitat conservation.