Atlantic Canada goose, birds, Branta canadensis, breeding, breeding grounds, Cackling goose, Canada goose, diet, dusky goose, giant goose, habitat, interior goose, migration, Moffitt's goose, numbers, Vancouver goose
(originally published to Helium writing site, now gone)
The Canada goose, or Branta canadensis, is native to North America. It has a black or dark brown head and neck, with a white chin. This distinguishes it from other geese except for the Barnacle goose. Its back and wings are brown, while it has a white chest and belly.
Seven subspecies of the Canada goose are the Atlantic Canada goose, the interior, giant, Moffitt’s, Vancouver, dusky, and part of the “lesser complex” Canada goose. A number of other subspecies were split off to form a new species called the Cackling goose in 2004. The Canada goose’s size and plumage vary among its subspecies. The smaller subspecies are similar to the Cackling goose.
Their height varies from 30 to 45 inches, while wingspan usually measures from 50 to 70 inches. An adult male weighs 7 to 14 pounds. The female is about 10 per cent shorter than the male and is slightly lighter at 6 to 12 pounds. A giant Canada goose was found with a wingspan of 88 inches and weighing 24 pounds. Their honk also differs between the male and female. The bird has a life span of between 10 and 24 years in the wild.
Breeding grounds are various habitats in Canada and northern United States. It is most populous in the Great Lakes region. The bird nests in raised areas near water, sometimes choosing a beaver’s lodge. It lays its eggs in shallow depressions which it lines with plant matter and down. Over-hunting and destruction of habitat in the 19th and early 20th centuries led to a substantial fall in numbers. The giant Canada goose was thought to be extinct by the 1950s but a small group was found in 1962 in Rochester, Minnesota. Populations of most subspecies recovered significantly after game laws were tightened and preservation programs were put in place. Numbers of the dusky Canada goose may still be in decline.
The Canada goose naturally migrates thousands of miles. Bird ringing has shown that members of the “lesser complex” subspecies have flown to northern Europe. The Canada goose is also found on eastern Siberia’s Kamchatka Peninsula, as well as in eastern China, and in Japan. They traverse the United States in large flocks in V-shaped formation, marking the change of season to spring or fall. Some groups, such as in the Pacific Northwest with its mild climate and where there are few predators, no longer migrate.
The bird was first introduced into Europe in the late 17th century to bolster the waterfowl collection of Great Britain’s King James II. In 1991, there were over 60,000 Canada geese in the United Kingdom. They can also be found in Netherlands, Belgium and Scandinavia. They inhabit many parks, sometimes becoming a problem. They were taken to New Zealand in the 19th century as a game bird but have become a nuisance in some areas.
They eat a diet of green plant matter, including various grasses. The bird grabs blades of grass with its bill, and then rips them out of the ground by jerking its head. It also eats grain such as wheat, corn, rice and beans. When in water, it feeds from the silt on the bottom, and will also eat aquatic plants like seaweed.
The Canada goose breeds from its second year of life. It has one mate and they usually stay together throughout their lives. About four to eight eggs are laid. Potential nest raiders include the Arctic fox, red fox, common raven, American crow, large gulls, and bears. Both birds will protect the nest during the 25-28 day incubation period, although the female will spend more time doing this than the male. They lose their flight feathers during this time.
A family often walks in single file between its nest and the water, one parent at the front of the procession and the other at the back. The pair are fiercely protective of their young and can be quite violent in warding off anything they feel might be a predator, including any birds, other geese, and humans. They give a first warning of a hissing sound and if that doesn’t work they can attack. The Canada goose can be very vocal at other times too. Sometimes families link up and form a creche or colony. The goslings acquire their flight feathers at around six to nine weeks of age. They migrate with their parents in fall and will stay with them until after the flock has returned to their summer habitat. Adults are not often preyed upon, but they can be vulnerable to the bald eagle and, to a lesser extent, foxes, wolves, coyotes, owls and the golden eagle.
The population of these non-migratory birds has risen strongly and they are now often found in parks, gold courses and parking lots. The Canada goose’s adaptability has resulted in it becoming the most common waterfowl in the United States. In Wichita, for example, numbers are estimated to have grown from 1,600 to 71,600 birds between 1983 and 2011. Unfortunately, they have become pests in some locations, and are thought to be responsible for high fecal coliforms in some beach areas. The hunting season has been extended and noise markers used in some places. Efforts to modify habitats, relocation, and culling occurred after a US Air Force plane went down in 1995 after it hit a flock of Canada geese, killing all 24 crew.