Our Animals - Canada Goose
Our Animals > Canada Goose
The Canada Goose (Branta canadensis) is a wild goose belonging to the genus Branta, which is native to arctic and temperate regions of North America, having a black head and neck, white patches on the face, and a brownish-gray body. It is often called the Canadian Goose, but that name is not the ornithological standard, or the most common name.
The Canada Goose was one of the many species described by Linnaeus in his 18th-century work Systema Naturae. It 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 specific epithet canadensis is a New Latin word meaning "from Canada". According to the Oxford English Dictionary, the first citation for the 'Canada Goose' dates back to 1772. The Cackling Goose was formerly considered to be a set of subspecies of the Canada Goose. A recent proposed revision by Harold Hanson suggests splitting Canada Goose into six species and 200 subspecies. The radical nature of this proposal has provoked surprise in some quarters, such as Rochard Banks of the AOU, who urges caution before any of Hanson's proposals are accepted.
The black head and neck with white "chinstrap" distinguish the Canada Goose from all other goose species, with the exception of the Barnacle Goose, but the latter has a black breast, and also 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) wingspan. The male usually weighs 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 10% smaller than its male counterpart, and has a different honk. An exceptionally large male of the race B. c. maxima, the "giant Canada goose" (which rarely exceed 8 kg/18 lb), weighed 10.9 kg (24 pounds) and had a wingspan of 2.24 m (88 inches). This specimen is the largest wild goose ever recorded of any species. The life span in the wild is 10–24 years.
Distribution and habitat
This species is native to North America. It breeds in Canada and the northern United States in a variety of habitats. Its nest is usually located in an elevated area near water such as streams, lakes, ponds and sometimes on a beaver lodge. Its 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.
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.
In recent years, Canada Geese populations in some areas have grown substantially, so much so that many consider them pests (for their droppings, the bacteria in their droppings, noise and confrontational behavior). This problem is partially due to the removal of natural predators and an abundance of safe, man-made bodies of water (such as on golf courses, public parks and beaches, and in planned communities).
Contrary to its normal migration routine, large flocks of Canada Geese have established permanent residence in the Chesapeake Bay and in Virginia's James River regions, and in the Triangle area of North Carolina (Raleigh, Durham, Chapel Hill), and nearby Hillsborough. The parks and golf courses of Scottsdale, Arizona, have an unusually high concentration of permanent Canada geese.
Outside North America
Canada Geese have reached northern 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 introduced in Europe, and have established populations in Great Britain, the Netherlands, Belgium, Germany, and Scandinavia. Semi-tame feral birds are common in parks, and have become a pest in some areas. The geese were first introduced in Britain in the late 17th century as an addition to King James II's waterfowl collection in St. James's Park.
Canada Geese were introduced as a game bird into New Zealand and have also become a problem in some areas. The introduction of a foreign species into the New Zealand is disrupting the existing biological relationship structures. On the South Island, it is estimated that the population of goose is increasing at an astonishing rate and is threatening local populations. Some even go as far to claim the goose as a pest. If the goose continues at its current high growth rate, the situation will become increasingly problematic.
Looking for food on a partially frozen pond 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 California to the Great Lakes, some of the population has become non-migratory due to adequate winter food supply and a lack of former predators.
Canada Geese are herbivores although they sometimes eat small insects and fish. Their diet includes green vegetation and grains. The Canada Goose eats a variety of grasses when on land. It feeds by grasping a blade of grass with the bill, then tearing it with a jerk of the head. The Canada Goose also eats grains such as wheat, beans, rice, and corn when they are available. In the water, it feeds from silt at the bottom of the body of water. It also feeds on aquatic plants, such as seaweeds. In urban cities, they are also known to pick food out of garbage bins.
During the second year of their lives, Canada Geese find a mate. They are monogamous, and most couples stay together all of their lives. If one is killed, the other may find a new mate. The female lays 3–8 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, Northern Raccoons, Red Foxes, large gulls, Common Raven, American Crows and bears. During this incubation period, the adults lose their flight feathers, so they cannot fly until their eggs hatch after 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. While protecting their goslings, parents often violently chase away nearby creatures, from small blackbirds 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. Although parents are hostile to unfamiliar geese, they may form groups of a number of goslings and a few adults, called crèches. The offspring enter the fledging stage any time from 6 to 9 weeks of age. They 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 (beyond humans) can be taken by Coyotes, Red Foxes, Gray Wolves, Snowy Owls, Great Horned Owls, Golden Eagles and, most often, Bald Eagles.