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Canada Goose (Branta canadensis) - Wiki
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Canada Goose
From Wikipedia, the free encyclopedia
[Photo] Canada Goose (Branta canadensis) head detail. Specialized for plant feeding. Location: Fairview Heights, Illinois. Date: 24 June 2006. Author: Robert Lawton (http://commons.wikimedia.org/wiki/User:Rklawton)
The Canada Goose (Branta canadensis), also referred to in North America as the Canadian Goose, belongs to the Branta genus of geese, which contains species with largely black plumage, distinguishing them from the grey species of the Anser genus.
The species name, canadensis, is a New Latin word meaning "of Canada".
Appearance
The black head and neck with white "chinstrap" distinguish this goose from all except the Barnacle Goose, but the latter has a black breast, and grey, rather than brownish, body plumage. There are seven subspecies of this bird, of varying sizes and plumage details, but all are recognizable as Canada Geese. Some of the smaller races can be hard to distinguish from the newly-separated Cackling Goose.
This species is 76-110 cm (30-43 in) long with a 127-180 cm (50-71 in) wing span. Males usually weigh 3.2???6.5 kg, (7???14 pounds), and can be very aggressive in defending territory. The female looks virtually identical but is slightly lighter at 2.5???5.5 kg (5.5???12 pounds), generally are 10% physically smaller then their male counterparts, and has a different honk. An exceptionally large male of the race B. c. maxima, the Giant Canada Goose (which rarely exceed 8 kg/17.6 lbs), weighed 11.3 kg (25 pounds) and had a wingspan of 224 cm (88 inches). The average life span in the wild is 10-25 years.
Behavior and habitat
These birds feed mainly on plant material. When feeding in water, they submerge their heads and necks to reach aquatic plants, sometimes tipping forward like a dabbling duck. They depend largely on grasses, sedges, or other green monocots during summer. Flocks of these geese also often feed on leftover cultivated grains in fields, especially during migration or in winter. Corn may comprise almost the whole seasonal diet of some migrants.
During the second year of their lives, Canada Geese find a mate. Most couples stay together all of their lives. If one is killed, the other may find a new mate. The female lays 4-8 eggs and both parents protect the nest while the eggs incubate, but the female spends more time at the nest than the male. Known egg predators include Arctic Foxes, Red Foxes, all large gulls, Common Raven, American Crows and bears. During this incubation period, the adults lose their flight feathers, so that they cannot fly until after their eggs hatch. This stage lasts for 25-28 days.
Adult geese are often seen leading their goslings in a line, usually with one parent at the front, and the other at the back of the "parade". While protecting their goslings, parents often violently chase away nearby creatures, from small blackbirds to other geese, to humans that approach, after warning them by giving off a hissing sound. Most of the species that prey on eggs will also take a gosling, if there's an opportunity. However, geese may form groups of a number of goslings and a few adults, called cr??ches. The offspring enter the fledging stage anytime from 6 to 9 weeks of age. The young do not leave their parents until after the spring migration, when they return to their birthplace. Once they reach adulthood, Canada Geese are rarely preyed on, but can be taken by Coyotes, Red Foxes, Gray Wolves, Snowy Owls, Great Horned Owls, Golden Eagles and, most often, Bald Eagles.
This well-known species is native to North America. It breeds in Canada and the northern United States in a variety of habitats. However, the nest is usually located in an elevated area near water, sometimes on a beaver lodge. The eggs are laid in a shallow depression lined with plant material and down. The Great Lakes region maintains a very large population of Canada Geese.
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, such as the Pacific Northwest, due to a lack of former predators, some of the population has become non-migratory.
Through different areas of North America, non-migratory Canada Goose populations have been on the increase. They frequent golf courses, parking lots and urban parks, which would have previously hosted only migratory geese on rare occasions. Their adaptability to human-altered areas has made this the most common waterfowl species in North America. In many areas, these non-migratory Canada Geese are now regarded as "pests". They are suspected of being a cause of an increase in high fecal coliforms at beaches. An extended hunting season and the use of noise makers have been used in an attempt to disrupt suspect flocks over the course of several years.
Outside North America
Canada Geese have reached western Europe naturally, as has been proved by ringing recoveries. The birds are of at least the subspecies parvipes, and possibly others. Canada Geese are also found naturally on the Kamchatka Peninsula in eastern Siberia, eastern China, and throughout Japan.
Greater Canada Geese have also been widely introduced in Europe, and have established populations in Great Britain, the Netherlands, and Scandinavia. Semi-tame feral birds are common in parks, and have become a pest in some areas. It is now proven that most Scandinavian and some British birds have established a migration pattern. The geese were first introduced in the Britain in the late 17th century as an addition to King James II's waterfowl collection in St. James's Park. Finally, Canada Geese were introduced as a game bird into New Zealand, but they have also become a problem in some areas there.
By the early 20th century, over-hunting and loss of habitat in the late 1800s and early 1900s had resulted in a serious decline in the numbers of this bird in its native range. The Giant Canada Goose subspecies was believed to be extinct in the 1950s until, in 1962, a small flock was discovered wintering in Rochester, Minnesota by Harold Hanson of the Illinois Natural History Survey. With improved game laws and habitat recreation and preservation programs, their populations have recovered in most of their range, although some local populations, especially of the subspecies occidentalis, may still be declining.
Systematics
The Cackling Goose was originally considered to be the same species or a subspecies of the Canada Goose, but in July 2004 the American Ornithologists' Union's Committee on Classification and Nomenclature split the two into two species, making Cackling Goose into a full species with the scientific name Branta hutchinsii. The British Ornithologists Union followed suit in June 2005.
The AOU has divided the many associated subspecies between both animals. To the present species were assigned:
Atlantic Canada Goose, Branta canadensis canadensis
Interior Canada Goose, Branta canadensis interior
Giant Canada Goose, Branta canadensis maxima
Moffitt's Canada Goose, Branta canadensis moffitti
Vancouver Canada Goose, Branta canadensis fulva
Dusky Canada Goose, Branta canadensis occidentalis
part of "Lesser complex", Branta canadensis parvipes
The distinctions between the two geese have led to a great deal of confusion and debate among ornithologists. This has been aggravated by the overlap between the small types of Canada Goose and larger types of Cackling Goose. The old "Lesser Canada Goose" was believed to be a partly hybrid population, with the birds named taverneri considered a mixture of minima, occidentalis and parvipes. In addition, it has been determined that the Barnacle Goose is a derivative of the Cackling Goose lineage, whereas the Hawaiian Goose is an insular representative of the Canada Goose.
In popular culture
The Canada Goose was depicted on the 1986 series Canadian $100 note.
The 1996 movie Fly Away Home was about a young girl who finds and raises a brood of orphaned Canada Goslings and attempts to induce them to migrate after the birds reach adulthood.
A Canada Goose was used as the logo for the tail section of Canadian Airlines before the airline merged with Air Canada.
An episode of Dirty Jobs had host Mike Rowe checking a gaggle of Canada Geese for Avian Flu.
http://en.wikipedia.org/wiki/Canada_Goose
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Scientific Name: Branta canadensis (Linnaeus, 1758)
Common Names: Canada Goose, Canadian Goose
Synonyms: Anas canadensis Linnaeus, 1758 |
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