In contrast to other goose species, Brant are characterized by their extensive use of native coastal habitats outside the breeding season.
The Brant is a small dark goose that occurs throughout much of the northern hemisphere. In contrast to other goose species, Brant are characterized by their extensive use of native coastal habitats outside the breeding season.
Three to four subspecies are recognized mainly on the basis of plumage characteristics. The two/three North American subspecies are further separated into four sub-populations based on genetics, location of breeding and wintering areas, and migration routes.
This goose breeds from the low to the high Arctic, and migrates long distances to wintering areas. Different sub-populations nesting in arctic Canada and Alaska winter in areas as distant and widely separated as Baja California, the Puget Sound, the coastline of the mid-Atlantic states, and Ireland.
In summer, salt marshes, especially those containing the graminoids Carex and Puccinellia, are key habitats for nesting and raising young.
These same habitats, along with large freshwater lakes with abundant moss and sedge shorelines, are also used during the flightless moult.
Wintering locations are usually characterized by an abundance of native intertidal plants used as forage, particularly the seagrass, Zostera; no other species of goose relies so heavily on a single plant species during the non-breeding season.
In contrast to European populations, Brant wintering in North American have, for the most part, not switched to agricultural habitats.
Like other geese, this species provides bi-parental care, accompanies its young through their first migration, and usually mates for life. Brant show fidelity to both wintering and breeding areas.
In the low Arctic, Brant often breed in relatively dense colonies, but in the high Arctic nesting is more dispersed. During brood-rearing, the availability and abundance of salt marsh foraging habitat directly affects growth and recruitment of goslings, thereby influencing local population dynamics.
During winter, their strong dependence on certain food plants makes them vulnerable to occasional heavy losses from starvation, more so than most other geese.
Further, oceanographic conditions experienced at wintering locations directly affect their subsequent breeding condition and reproductive performance.
These vulnerabilities necessitate careful population-monitoring and regulation of hunting.