Breed name: Goose
Description: The black head and neck with a white "chinstrap" distinguish the Canada goose from all other goose species, with the exception of the cackling goose and barnacle goose (the latter, however, has a black breast and grey rather than brownish body plumage).
The seven subspecies of this bird vary widely in size and plumage details, but all are recognizable as Canada geese. Some of the smaller races can be hard to distinguish from the cackling goose, which slightly overlap in mass. However, most subspecies of the cackling goose (exclusive of Richardson's cackling goose, B. h. hutchinsii) are considerably smaller. The smallest cackling goose, B. h. minima, is scarcely larger than a mallard. In addition to the size difference, cackling geese also have a shorter neck and smaller bill, which can be useful when small Canada geese comingle with relatively large cackling geese. Of the "true geese" (i.e. the genera Anser, Branta or Chen), the Canada goose is on average the largest living species, although some other species that are geese in name, if not of close relation to these genera, are on average heavier such as the spur-winged goose and Cape Barren goose.
Like most geese, the Canada goose is naturally migratory with the wintering range being most of the United States. The calls overhead from large groups of Canada geese flying in V-shaped formation signal the transitions into spring and autumn. In some areas, migration routes have changed due to changes in habitat and food sources. In mild climates from south western British Columbia to California to the Great Lakes, some of the population has become nonmigratory due to adequate winter food supply and a lack of former predators.
Males exhibit agonistic behavior both on and off breeding and nesting grounds. This behavior rarely involves interspecific killing. One documented case involved a male defending his nest from a brant goose that wandered into the area; the following attack lasted for one hour until the death of the brant. The cause of death was suffocation or drowning in mud as a direct result of the Canada goose's pecking the head of the brant into the mud. Researchers attributed it to high hormone levels and the brant's inability to leave the nesting area.