Canada Goose
Conservation status Least concern |

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Scientific classification |
Kingdom: |
Animalia
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Phylum: |
Chordata
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Class: |
Aves
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Order: |
Anseriformes
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Family: |
Anatidae
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Genus: |
Branta
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Species: |
B. canadensis
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Binomial name |
Branta canadensis
(Linnaeus,
1758) |
Subspecies |
B. c. occidentalis (Dusky Canada Goose)
B. c. fulva (Vancouver Canada Goose)
B. c. parvipes (Lesser Canada Goose)
B. c. moffitti (Moffitt's Canada Goose)
B. c. maxima (Giant Canada Goose)
B. c. interior (Interior Canada Goose)
B. c. canadensis (Atlantic Canada Goose)
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The Canada Goose (Branta canadensis)
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
Yellow plumage of gosling
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 are
hard to distinguish from the Cackling Goose (Branta hutchinsii), with which
the Canada Goose was long assumed to form one species; the
name Lesser Canada Goose is, confusingly, often applied to
B. hutchinsii.
This species is 90-100 cm long with a 160-175 cm wing
span. Males weigh 3.5–6.5 kg, (8–14 pounds), and can be very
aggressive in defending territory. The female looks
virtually identical but is slightly lighter at 3–5.5 kg
(7–12 pounds), and has a different honk.
Behaviour and habitat
Specialized for plant feeding
Example of a creche
Example of a parade
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. Flocks of these birds often feed on
leftover cultivated grains in fields, especially during
migration or in winter.
During the second year of their lives, Canada Geese find
themselves a mate. Most couples stay together all of their
lives. If one is killed, the other may find a new mate, and
divorce also occurs, though rarely.[1]
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. During that time, they lose their flight
feathers, so that they cannot fly until after their eggs
hatch. This period lasts for 25-28 days.
In some populations, up to 12% of the pairs are
homosexual. Both males and females may form same-sex
pairs. One study has observed that 18% of the males formed
same-sex pair bonds, while for females the ratios varied
between 6 and 12%. Courtship behavior is associated with
such couples, though copulation is not a prominent feature
of same-sex pairs.[2]
Adult geese are often seen leading their goslings in a
line with one parent at the front, and the other at the back
of the "parade". While protecting their young, parents often
violently chase away nearby creatures, from small blackbirds
to other geese, to humans that approach. However, geese may
form groups of a number of goslings and a few adults, called
crčches. The young do not leave their parents until after
the spring migration, when they return to their birthplace.
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, it is naturally
migratory, the wintering range being most of the US. 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.
If a goose feels threatened by another creature it will
usually warn the creature by giving off a hissing sound.
Other locations
Branta canadensis Canada Goose
distribution: yellow:summer; blue:winter;
green:year-round
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.
Branta canadensis, by
John James Audubon
Greater Canada Geese have also been widely introduced in
Europe, and have established feral 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. They have adapted well to urban
environments, especially those with well-trimmed lawns and
large ponds, such as golf courses and city parks.
Taxonomy
Canada Goose in mid-flight
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 of both animals:
- Canada Goose (also known as Greater Canada Goose)
- Atlantic Canada Goose (Branta canadensis
canadensis)
- Interior Canada Goose (Branta canadensis
interior)
- Giant Canada Goose (Branta canadensis maxima)
- Moffit'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)
- Cackling Goose (also known as Lesser Canada Goose or
Small Canada Goose)
- Richardson's Cackling Goose (Branta
hutchinsii hutchinsii)
- Bering Cackling Goose (Branta hutchinsii
asiatica)
Conservation status: Extinct (c.1929)
- Aleutian Cackling Goose (Branta hutchinsii
leucopareia)
- Small Cackling Goose (Branta hutchinsii
minima)
- part of "Lesser complex" (Branta hutchinsii
taverneri)
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.
See also
- 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 get them to migrate after the birds reach
adulthood.
- A Canada Goose was used as the logo for the tail
section of Canadian Airlines last livery before the
airline merged with Air Canada.
Notes
- ^
Bruce Bagemihl, Biological Exuberance: Animal
Homosexuality and Natural Diversity, St.
Martin's Press, 1999; p.485
- ^
Bruce Bagemihl, Biological Exuberance: Animal
Homosexuality and Natural Diversity, St.
Martin's Press, 1999; pp.483-485
References
- BirdLife International (2006).
Branta canadensis. 2006
IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 11 May 2006.
External links
Gallery
Spring Goslings,
Thames Ditton, UK
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Breeding pair and goslings, Canada.
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