E-Fauna BC: Electronic Atlas of the Wildlife of British Columbia

Branta bernicla (Linnaeus)
Brant
Family: Anatidae

Species account author: Jamie Fenneman

© Tim Zurowski  Email the photographer   (Photo ID #8753)


Distribution of Branta bernicla in British Columbia.
(Click on the map to view a larger version.)
Source: Distribution map provided by Jamie Fenneman for E-Fauna BC

Species Information

Adult
The upperparts (back, scapulars, centre of the rump, upperwing coverts) are dark blackish-brown, contrasting slightly with the blacker flight feathers. The sides of the rump and long uppertail and undertail coverts are white, almost completely concealing the short, black tail. The breast and belly are dark blackish-brown, with dark brown extending onto the white sides and flanks as a series irregular bars. The head, neck, upper portion of the mantle, and uppermost breast are black, sharply demarcated but contrasting only slightly with the dark brown underparts; there is a series of short, diagonally white streaks around the top of the neck forming a ‘necklace’. The iris is dark, the relatively short, stubby bill is black, and the legs and feet are black.

Juvenile
This plumage is held until late fall (November) of the first year. Juvenal-plumaged birds are similar to adults, but have fine pale terminal bars on the upperpart feathers (giving the upperparts a finely barred appearance, especially on the upperwing coverts) and there is usually no white ‘necklace’ on the completely black head and neck. In addition, the breast, belly, sides, and flanks are wholly dark sooty-grey and lack the bold white area along the sides and flanks.

Measurements
Total Length: 62.5-64 cm
Mass: 1,000-1,800 g

Source: Reed et al. (1998); Sibley (2000)

Biology

Identification

The identification of this species is straightforward in all plumages. The only similar goose species, Canada Goose and Cackling Goose, are easily distinguished by their white chin strap (head completely black in Brant). These species are also noticeably paler and browner than Brant, and show less extensive white on the uppertail coverts when in flight.
Vocalizations

This species is often very vocal. Individuals produce a soft, gargling rrot or cronk (sometimes extended into a drawn-out, wavering crrrronk when alarmed) as well as a hard cut-cut or cut-cut-cut-cronk when in flight. Foraging and migrating flocks can often be heard producing a constant, low, murmuring chorus of guttural notes.

Source: Reed et al. (1998); Sibley (2000)

Breeding Ecology

This species is a non-breeding migrant and winter visitor to B.C.
Foraging Ecology

This species feeds only in or adjacent to the marine environment in B.C., except for occasional vagrants in the interior. During winter and fall migration, the diet of this species is almost entirely composed of eel-grass and green seaweed (sea lettuce [Ulva spp.]), which are gathered from shallow intertidal areas during medium to low tides. In addition, spring migrants also consume large amounts of herring roe, and herring spawning sites are typically used by this species as major stopover sites during spring migration. It also forages occasionally in upland habitats, where it grazes on grasses and salt marsh vegetation immediately above the beach. Intertidal vegetation is gathered either while walking within the intertidal zone at low tides or, at higher tides, by utilizing a ‘tipping-up’ foraging method that is common to many waterfowl. During this process, the bird dips the front half of its body underwater and elevates the back half of the body, using its relatively long neck to reach to the bottom and graze on submerged vegetation that would otherwise be completely out of reach. It also picks floating vegetation and seaweed from the surface of the water. This species usually occurs in small to medium-sized flocks when feeding, although large flocks of up to 1,000+ may congregate at spring stopover sites. It sometimes associates with other goose species, such as Canada Goose or Greater White-fronted Goose, especially when foraging in upland habitats (lawns, golf courses, etc.).

Source: Reed et al. (1998)

Habitat


This species is restricted to marine habitats along the coast of B.C, although it occasionally forages on open grassy areas (pastures, lawns, parks, golf courses, brackish marshes) where they occur immediately adjacent to the intertidal area. Most foraging birds are found in the intertidal zone of shallow, often sheltered, mud- or sand-bottomed bays and estuaries where there is an abundance of eel-grass or sea lettuce. It also congregates during spring migration along more exposed coastlines in areas where large numbers of Pacific Herring are spawning. When not foraging, birds usually roost in offshore waters up to several kilometers from shore. Migrating birds can be found over any exposed or sheltered marine waters, including pelagic waters far off the outer coast of the province. Vagrants in the interior have been found on freshwater lakes and ponds, but these habitats are very rarely used along the coast.

Source: Campbell et al. (1990a); Reed et al. (1998)

Distribution

Global Range

Breeds in arctic regions of North America from the coast of western Alaska east to Baffin Island, and north throughout the Canadian arctic islands to Ellesmere Island. It also breeds along the northern coast of Greenland, in coastal areas of northern Siberia, on Spitsbergen, and along the northeastern coast of Russia. It winters in several discrete areas of the northern hemisphere, including the Pacific coast of North America, the coast of eastern Asia, the central Atlantic coast of the United States, and Europe.
BC Distribution

Winter
Very local as a wintering bird throughout its range, including British Columbia. It is locally fairly common on the Queen Charlotte Islands (Skidegate Inlet, Masset) and in the Lower Mainland region of the south coast (Tsawwassen, Boundary Bay) but is uncommon elsewhere throughout the Strait of Georgia and Strait of Juan de Fuca. It is also rare along the west coast of Vancouver Island in winter.

Migration and Vagrancy
The Brant is best known as a spring migrant in marine habitats along the coast of British Columbia. Flocks occur primarily in nearshore waters (including sheltered waters such as the Strait of Georgia and Strait of Juan de Fuca) and are fairly common to locally common along the entire coast. The largest concentrations of birds occur in areas with significant herring spawning events in early spring. In contrast, however, fall migrants occur primarily over offshore pelagic waters as they fly directly from staging areas in the Alaska Peninsula to wintering grounds along the Pacific coast of the United States and Mexico. As a result, fall migrants are relatively uncommon along the coast of B.C., particularly in the sheltered waters of the Strait of Georgia and the Strait of Juan de Fuca.

Spring migrants reach the southern coast of B.C. early, with the first flocks appearing in late February and increasing in numbers to reach a peak in late March or April; northward-bound flocks continue to move through the south coast through April and early May, with occasional flocks lingering into late May or, rarely, early June. On the north coast, including the Queen Charlotte Islands, the timing is spring migration is remarkably consistent with that on the south coast and occurs from February through May, peaking in April. Localized peak northward movements at various locations along the coast are generally related to slight differences in the timing of local herring spawning events. This species rare to locally uncommon as a non-breeder along the coast throughout the summer.

Fall migrants first appear along the coast in late August, with southward migration occurring throughout September and October. Most fall migrants have left the south coast of B.C. by late November, and only wintering populations (which arrive primarily in late October and early November) remain. Most fall migrants migrate en masse well offshore in late October or early November, and are rarely observed in B.C.

This species is a casual vagrant during spring (March) and fall (August-December) in the southern and central interior of the province, and is accidental during fall migration in the Peace River area of northeastern B.C.

Source: Campbell et al. (1990a)

Conservation

Population and Conservation Status

Wintering populations of Brant declined drastically all along the Pacific coast during the first half of the 20th century, primarily due to excessive hunting pressures and degradation of wintering and migratory habitats. The most catastrophic declines in British Columbia occurred in the 1950s and 1960s, when this species went from being a locally abundant wintering bird to a very uncommon species along the south coast. Wintering populations have remained low for the past 40-50 years, although there are rather significant increases in recent years following the permanent closure of the hunting season for Brant in the province. The remaining wintering population on the south coast was virtually restricted to Boundary Bay and Tsawwassen in the Lower Mainland at the time when the hunting ban came into effect, but the species now occurs widely throughout the Strait of Georgia and Strait of Juan de Fuca during the winter (albeit still in relatively low numbers away from a few core sites). Several thousand Brant are now recorded on Christmas Bird Counts along the south coast, which is a significant improvement over the <100 individuals that were detected at the lowest population levels in the 1970s and 1980s.

A new threat to Brant in B.C., however, is the excessive human disturbance of migratory flocks at traditional stopover sites along the coast of B.C., especially along the eastern coast of Vancouver Island (Comox to Nanaimo). This area supports a major herring spawning event in early spring, and a large percentage of the Pacific flyway population of Brant utilize this area to increase fat reserves before embarking on the next leg of their journey which takes them north to the south coast of Alaska. These flocks have a short period on which to consume large amounts of herring roe and subsequently gain sufficient fat reserves to complete the journey and breed successfully. A combination of major declines in herring stocks in this region due to overfishing and rapidly increasing rates of human disturbance to foraging flocks has led to significant declines in the number of Brant detected at these traditional stopover sites during the spring migration. This species is unusually sensitive to disturbance, and will fly or move into open water and cease foraging with even moderate levels of harassment. The rapidly increasing human population along the east coast of Vancouver Island has put severe pressure on the beach and shoreline habitats that are required by Brant and this has recently led to conflicts between human users and Brant. The annual Brant Festival in Parksville was initiated to bring public attention to this problem, and actions have recently been taken to close large sections of shoreline to human traffic during the critical March-April period when Brant are using the beaches. This is a recent development, however, and has not yet had noticeable impacts on the number of birds using the beaches. If these management options are retained into the future, and if penalties levied against individuals who ignore the area closures are consistently applied, there is some hope that the declines in the migratory populations of Brant may be halted or even reversed over the coming decades.

Because of these declines and the sensitivity of the species, the Brant is currently recognized as ‘blue-listed’ (species of special concern) by the B.C. Conservation Data Centre (CDC). Although not recognized by any federal or provincial bodies, the ‘Gray-bellied’ Brant is of particular conservation concern due to its relatively small population size (~11,000) and its highly localized wintering area, which coincides with an area of major human population growth (Puget Sound, Boundary Bay, Tsawwassen). This form may be a candidate for future listing as a conservation concern.

Source: Campbell et al. (1990a)

Taxonomy


This is a taxonomically complex species, with several discrete migratory populations, or ‘stocks’, in addition to several described subspecies. Three subspecies are currently recognized within the range of the species, two of which occur in North America and one in British Columbia. In addition, a morphologically and genetically distinct form that breeds only in the western Canadian arctic (primarily Melville Island) and winters in Puget Sound, Washington and Boundary Bay, B.C., is awaiting formal recognition as a distinct subspecies. This form is known as the ‘Gray-bellied’ Brant and is included here, despite its lack of formal taxonomic status. Although comprehensive genetic studies have not been carried out on this species, its taxonomic situation is similar to that of several other northern hemisphere goose species that have recently been split into multiple species (Canada Goose, Bean Goose). A similar situation may exist in the Brant, and there may be more than one species involved.

The subspecies/forms found in British Columbia are as follows:

Branta bernicla nigricans (Lawrence)
This subspecies is commonly known as the ‘Black Brant’. It breeds in the western North American arctic and winters along the Pacific cast of North America, and is also found in eastern Asia. It is by far the dominant form in British Columbia at all times of year. It is similar to the Gray-bellied Brant, which is much less common, but has blacker underparts that contrast more strongly with the white flanks but show almost no contrast with the black head and neck.

‘Gray-bellied Brant’ – undescribed taxon
This form breeds on Melville Island in the western Canadian arctic and winters primarily in Puget Sound, Washington (with smaller numbers wintering in Boundary Bay, B.C.). Small numbers are observed elsewhere along the coast of B.C. during migration particularly in the Strait of Georgia. This form is similar to B.b.nigricans, but has slightly paler greyish-brown underparts that contrast sharply with the black head and neck.

Source: Reed et al. (1998)

Status Information

Origin StatusProvincial StatusBC List
(Red Blue List)
COSEWIC
NativeS3MBlueNot Listed
BC Ministry of Environment: BC Species and Ecosystems Explorer--the authoritative source for conservation information in British Columbia.

Additional Range and Status Information Links

Additional Photo Sources

General References


Recommended citation: Author, Date. Page title. In Klinkenberg, Brian. (Editor) 2019. E-Fauna BC: Electronic Atlas of the Fauna of British Columbia [efauna.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [Accessed: 2020-02-19 8:01:13 PM]
Disclaimer: The information contained in an E-Fauna BC atlas pages is derived from expert sources as cited (with permission) in each section. This information is scientifically based.  E-Fauna BC also acts as a portal to other sites via deep links.  As always, users should refer to the original sources for complete information.  E-Fauna BC is not responsible for the accuracy or completeness of the original information.


© E-Fauna BC: An initiative of the Spatial Data Lab, Department of Geography, UBC