Branta canadensis

Branta canadensis is one the the fourteen species of true geese of the order Anseriformes. True geese are gregarious and occur only in the northern hemisphere, breeding in Arctic to Subartctic latitudes. There are approximately 12 to 14 recognized subspecies of B. canadensis, the most obvious difference being body size, ranging from the size of a large duck to a swan. In Oregon, eight subspecies of B. canadensis occur. Tied for largest, B. canadensis maxima is an introduced species that has become a breeding resident of Oregon. B. canadensis moffiti is the other of the large geese and is also a breeding resident of Oregon but also breeds throughout the western states. The cackiling goose, B. canadensis minima, has a distinctive call, the smallest body size, stubby neck and short bill. Arriving in Oregon mid October, the cackiling goose may depart in winter. B. canadensis leucopareia is a rare fall migrant of Oregon and a local winter resident on the coast. B. canadensis taverneri and B. canadensis occidentalis have a widespread distribtuion and are abundant, arriving in October and departing in April. All of the subspecies described except the two largest, B. candadensis maxima and B. canadensis moffitti, nest in Alaska or the Aleutian Islands. Some ornithologists suggest that each subspecies should become distinct species since they differ widely in habitat selection, winter mixing and roosting.

The species B. canadensis can be very long lived, captive individuals reaching up to 50 years of age.

The male and female are not sexually dimorphic. The neck of B. canadensis is long and black with a rounded, white chin strap. The bill and legs are are also brown. The upper plumage is of a darker brown color than the underparts. The rump and undertail covert feathers are a contrasting white. The tail is short and black. The length of the bird can range from 25 to 45 inches and the wingspan from 4.5 to 5.75 feet.

The habitat of B. canadensis includes any water body, parks, marsh lands and coplands. Nests are typically found onthe ground of an islet, shoreline point or cliff. Occasionaly a former eagle or osprey nest near water is used.The female constructs the nests of grass and vegetation, then lining with feathers and down. The male’s role is to guard the brooding female while the eggs incubates 4 to 7 white eggs for 25 to 30 days. Both adults play roles in raising young.

The voice of B. canadensis is similar in most populations, though can be higher in smaller birds. The cackling goose has a distinctly higher pitch, sounding more like a squeek or cackle, as the common name implies.

B. canadensis is native to North America. The species has been introduced in New Zealand and Great Britain. Only B. canadensis leucopareia is federally listed as threatened, in the state of Oregon it is listed as endangered.

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References

Burrows, R. and J. Gilligan (2003) Birds of Oregon. Lone Pine Publishing. Washington, Alberta.

Cogger, H.G., E. Gould, J. Forshaw, G. McKay and R.G. Zweifel (1993) The Encyclopedia of Animals. Fog City Press, San Francisco, California.

Sibley, D.A. (2000) National Audubon Society: The Sibley Guide to Birds. Alfred A. Knopf, New York.

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