Cackling Goose (Branta hutchinsii)

Cackling Goose

[order] ANSERIFORMES | [family] Anatidae | [latin] Branta hutchinsii | [authority] Richardson, 1832 | [UK] Cackling Goose | [FR] Bec-en-sabot du Nil | [DE] Hutschins Zwergkanadagans | [ES] Barnacla Canadiense | [NL] Kleine Canadese Gans

Subspecies

Monotypic species

Genus

The black geese of the genus Branta are waterfowl belonging to the true geese and swans subfamily Anserinae. They occur in the northern coastal regions of the Palearctic and all over North America, migrating to more southernly coasts in winter, and as resident birds in the Hawaiian Islands. Alone in the Southern Hemisphere, a self-sustaining feral population derived from introduced birds of one species is also found in New Zealand. one species has been described from subfossil remains found in the Hawaiian Islands, where it became extinct in prehistoric times. Another undescribed prehistoric species from the Big Island of Hawaii was extremely large and flightless; it is tentatively assigned to this genus due to being very peculiar. It is fairly certain that at least another species of this genus awaits discovery on the Big Island, judging from the facts that at least one species of Branta was found on every major Hawaiian island, and that remains of such birds have not been intentionally searched for on the Big IslandThe relationships of the enigmatic Geochen rhuax to this genus are unresolved. It was another prehistoric Big Island form and remains known only from some parts of a single bird’s skeleton, which were much damaged because the bird apparently died in a volcanic eruption, with the bones being found in an ash-filled depression under a lava flow. A presumed relation to the shelducks proposed by Lester Short in 1970 was generally considered highly unlikely due to that group’s biogeography, but more recently, bones of a shelduck-like bird have been found on Kauai. Whether this latter anatid was indeed a shelduck is presently undetermined. Several fossil species of Branta have been described. Since the true geese are hardly distinguishable by anatomical features, the allocation of these to this genus is somewhat uncertain. A number of supposed prehistoric grey geese have been described from North America, partially from the same sites as species assigned to Branta. Whether these are correctly assigned, meaning that the genus Anser was once much more widespread than today and that it coexisted with Branta in freshwater habitat which it today does only most rarely, is not clear. Especially in the case of B. dickeyi and B. howardae, doubts have been expressed about its correct generic assignment

Physical charateristics

Cackling Geese appear almost identical to Canada Geese: mottled gray-brown body, black legs, tail, neck, head and face, with a white chin strap stretching from ear to ear and a white rump band. Like Canada Geese, some Cackling Geese show a white collar at the base of the neck and/or a black chin-stripe dividing the white cheek patches. Cackling Geese are best distinguished from Canada Geese by overall body size, bill shape and size, and voice.

Cackling Geese are generally smaller than Canada Geese, although overlap in size between the larger subspecies of Cackling Geese and the smaller subspecies of Canada Geese can make identification by size alone difficult. The smallest Cackling Geese weigh about 3 to 4 lbs. (a little larger than a mallard) with the largest subspecies weighing as much as 7 lbs., whereas Canada Geese range in size from 5 to 15 lbs. Compared to Canada Geese, Cackling Geese have proportionally smaller, stubbier bills and higher-pitched voices.

Length of neck in flight can be a useful indicator of species (shorter for Cackling Geese, longer for Canada Geese); however, because geese can elongate or retract their necks, neck length can be difficult to determine in swimming or sitting birds. Due to their smaller size, Cackling Geese (especially B.h. minima) display a faster wingbeat than Canada Geese and their wings appear longer proportionally to their body size in flight.
Cackling Geese are primarily herbivores. The hard nail on their bill makes them efficient at grazing on grasses and plants while their long necks and the ability to tip-up enables them to forage on submerged aquatic plants. During migration and winter, Cackling Geese are highly gregarious, feeding in large flocks; individuals and family groupings are often found in flocks with Canada Geese. Cackling Geese become less gregarious with the approach of the breeding season as pairs leave the flock in search of nest sites. During the breeding season, they maintain their territory by threats and fights.

Listen to the sound of Cackling Goose

[audio:http://www.planetofbirds.com/MASTER/ANSERIFORMES/Anatidae/sounds/Cackling Goose.mp3]

Copyright remark: Most sounds derived from xeno-canto


wingspan min.: 160 cm wingspan max.: 175 cm
size min.: 90 cm size max.: 100 cm
incubation min.: 27 days incubation max.: 28 days
fledging min.: 68 days fledging max.: 28 days
broods: 1   eggs min.: 5  
      eggs max.: 6  

Range

North America : Central Canada

Habitat

On their tundra breeding grounds, Cackling Geese are always found near water. In winter and during migration they are found on inland lakes, rivers and marshes; in coastal salt marshes, bays and tidal flats; in brackish ponds, pastures and agricultural fields, and in grassy fields in urban and suburban parks with close proximity to water.

Reproduction

Cackling Geese are generally monogamous, forming life-long pair bonds during their second year (they may form a new pair bond with the loss of a mate). The various subspecies return to their traditional breeding areas year after year. The female selects the nest site, generally a slightly elevated location with good visibility near the edge of a pond or stream, on a small island in a pond or stream, or along the arctic coastal plain. One subspecies (B.h. leucopareia) breeds on steep slopes and cliff edges on fox-free islands in the Aleutians. Reuse of old nest sites is frequent. The nest is constructed of material available at the site (sedges, lichens, mosses) and feathers. The female incubates the eggs (generally 4-5) while the male stands guard.

Goslings are precocial and leave the nest within 24 hours of hatching, at which time they are able to walk, swim, dive and feed. The parents lead the brood to grazing areas but do not feed them. The young fledge approximately 6-7 weeks after hatching. The young leave the breeding areas with their parents and may remain with them throughout the first winter.

Feeding habits

On their tundra breeding grounds, Cackling Geese forage primarily on grasses, sedges, and berries. Prior to fall migration, they shift their diet to include higher amounts of sedge seeds and berries in order to gain fat. In wintering areas, Cackling Geese forage on grasses and agricultural crops, including winter wheat, alfalfa and barley.

Video Cackling Goose

httpv://www.youtube.com/watch?v=YI0QGWJ6zkg

copyright: youtube


Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend is not known, but the population is not believed to be decreasing sufficiently rapidly to approach the thresholds under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Cackling Geese are classed as migratory game birds and, together with Canada Geese, are among the top waterfowl harvested in the US and Canada. The conservation and management of Cackling Geese involves achieving a balance between too few geese and too many geese, and maintaining diversity of subspecies. In Washington, one subspecies of Cackling Goose is increasing (B.h. taverneri), one is declining (B.h. minima), and a third is recovering after a decline (B.h. leucopareia).

Cackling Geese are susceptible to lead poisoning from ingesting lead pellets in hunting areas and mortality from pesticides and other toxins. The decline in numbers of B.h. minima may be due to sport and subsistence hunting. Gas and oil development in the arctic may put some populations of Cackling Geese at risk.

Because all Canada Geese and Cackling Geese subspecies look generally alike, hunters must be educated to recognize the Aleutian Cackling Goose (B.h. leucopareia), which is a protected subspecies. Identification difficulties make it difficult to get accurate population totals of Cackling Geese.
Cackling Goose status Least Concern

Migration

Cackling Geese are long-distance migrants, following relatively direct, traditional flight paths between their breeding grounds in the arctic and their wintering grounds in the Pacific Northwest, California, and the gulf coast of Texas. Spring migration can begin as early as late January and is prolonged by stops at traditional sites to replenish nutrients before arriving at the breeding grounds. Fall migration begins in late August and can be non-stop or interrupted. Cackling Geese may reverse migration and return to a previous stop along the route if they encounter unfavorable weather.

Migrating flocks are comprised of family groups and individuals. Flocks are variable in size, depending on the subspecies and usually fly in a V formation. Flights usually begin at dusk but may occur at any time of the day. Migrating flocks generally fly at low elevation (300-1000 meters) and often maintain speeds of over 50 kilometers per hour for extended periods. In winter, Cackling Geese subspecies often flock together and also mix with Canada Geese.

Distribution map

Cackling Goose distribution range map

Leave a Reply