Branta canadensis

Canada Goose is the only North American goose commonly breeding from the Arctic Ocean to Florida and from Labrador west to the Aleutian Islands. Across this range a  number of  populations have developed, differing in size from “giant” forms to other much smaller subspecies. After completion of the TBBA field work, one small group, the Cackling Goose (B. hutchinsii; Mowbray et al. 2002, Am. Ornithol. Union 2004), was designated a separate species.

Canada Geese feed almost exclusively on plant material and therefore their diets vary seasonally depending on their nutritional needs and plant availability. Canadas are most familiar to urban dwellers as efficient, gregarious grazers on park lawns during much of the year. Goslings prefer green leaves, migrants arriving on their wintering grounds scavenge harvested fields for spilled grains, especially corn, or harvest crops planted for their use on wildlife refuges. Like other geese Canadas have also been used in selective locations to weed farm fields (Mowbray et al. 2002, RCT).

DISTRIBUTION. During the 1987-1992 field work seasons of the TBBA project, volunteers found only 5 confirmed breeding sites and one probable for Canada Geese. In Oklahoma atlasers found 49 confirmed and 43 probable breeding sites for this species (Young 2004). In Colorado atlasers found 141 confirmed, 22 probable and 39 possible sites in 202 of the state’s 1745 priority blocks. Of these 202 blocks, 56 were east of the 105^th meridian on the eastern plains in habitat similar to the Texas Panhandle. Another  49 blocks were between the 105^th and 106^thmeridian where most of Colorado’s largest cities are located (Winn 1998).

Outside these states, Canada Geese breed through most of Alaska, Canada and the lower 48 United States. Breeding is rare in Arizona and southern California. These geese winter from southern Alaska and south Canada to northern Mexico (Howell and Webb 1995, Am. Ornithol. Union 1998, Mowbray et al. 2002, Sauer et al. 2007).

SEASONAL OCCURRENCE. Most Canada Geese wintering commonly to abundantly in some areas of Texas, depart in March. Breeding by the few remaining geese, probably occurs from April to early August, based on atlas data from Colorado. The first southbound migrants arrive in Texas in late September though most arrive in late October  (Oberholser 1974, Winn 1998, Lockwood and Freeman 2004)).

BREEDING HABITAT. Breeding habitats used by Canada Geese in nearby states include:  wetlands (lakes, streams marshes) and riparian areas in Colorado (Winn 1998). In Oklahoma the atlas mentions ponds, marshes and reservoirs (Young 2004). Within these habitats nests are built on the ground, in emergent vegetation or on platforms or low stumps. A depression in the ground or in vegetation is lined by the female with sticks, grasses, cattails or rushes.  A further lining of down feathers is added during egg-laying. The structure has an outside diameter of 38-94 cm (15-36 in), inside diameter 15-33 cm (6-13 in) and a depth of 9-11 cm (3.5-4.5 in; Harrison 1979).

In the nest the female lays about 5-6 (range 2-8) creamy or dirty white eggs at about 1.5 day intervals. The eggs become nest-stained during the 25-28 day incubation by the female. The precocial; goslings are fully covered with down when they leave the nest within 24 hours after hatching, able to walk, swim, feed, and dive. The young are able to fly 6-9 weeks after hatching and generally remain with their parents until migration (Harrison 1979, Mowbray et al. 2002).

STATUS. In contrast to the TBBA findings, nesting was not reported historically (Oberholser 1974). Lockwood and Freeman (2004) mention small numbers of summer residents in the Panhandle with some breeding records. Thus  breeding by Canada Geese is a recent phenomena in this state. The population in North America is expanding with North American Breeding Bird Survey data indicating a statistically significant annual population change of +7.3% from 1083 routes across this area during 1980-2006 (Sauer et al. 2007). This increase is partly due to very rapid expansion of some introduced populations, some of which have become management problems, especially in urban areas (Mowbray et al. 2002).

Although the breeding population is tiny at present in Texas, the presence of a large wintering population for much of the year, makes the future of this species in Texas seem secure, in spite of its popularity as a game bird.

Text by Robert C. Tweit (2008)

Literature cited.

American Ornithologists’ Union. 1998. Checklist of North American birds, 7^thed. Am, Ornithol. Union, Washington, DC.

American Ornithologists’ Union. 2004. Forty-fifth supplement to the American Ornithologists’ Union Checklist of North American birds. Auk 121: 985-995.

Harrison, H. H. 1979. A field guide to western birds’ nests. Houghton Mifflin, Boston, MA.

Howell, S. N. G. and S. Webb. 1995. A guide to the birds of Mexico and northern Central America. Oxford University Press, New York.

Lockwood, M. W. and B. Freeman. 2004. The TOS handbook of Texas birds. Texas A&M University Press, College Station.