The Canada goose (Branta canadensis), or Canadian goose, is a large wild goose with a black head and neck, white cheeks, white under its chin, and a brown body. It is native to the arctic and temperate regions of North America, and it is occasionally found during migration across the Atlantic in northern Europe. It has been introduced to the United Kingdom, Ireland, Finland, Sweden, Denmark, New Zealand, Japan, Chile, Argentina, and the Falkland Islands. Like most geese, the Canada goose is primarily herbivorous and normally migratory; often found on or close to fresh water, the Canada goose is also common in brackish marshes, estuaries, and lagoons.
Extremely adept at living in human-altered areas, Canada geese have established breeding colonies in urban and cultivated habitats, which provide food and few natural predators. The success of this common park species has led to its often being considered a pest species because of its excrement, its depredation of crops, its noise, its aggressive territorial behavior toward both humans and other animals, and its habit of stalking and begging for food, the latter a result of humans disobeying artificial feeding policies toward wild animals.
Description & appearanceThe 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 and Branta), 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.
Canada geese range from 75 to 110 cm (30 to 43 in) in length and have a 127–185 cm (50–73 in) wingspan. Among standard measurements, the wing chord can range from 39 to 55 cm (15 to 22 in), the tarsus can range from 6.9 to 10.6 cm (2.7 to 4.2 in) and the bill can range from 4.1 to 6.8 cm (1.6 to 2.7 in). The largest subspecies is B. c. maxima, or the giant Canada goose, and the smallest (with the separation of the cackling goose group) is B. c. parvipes, or the lesser Canada goose. An exceptionally large male of race B. c. maxima, which rarely exceed8 kg (18 lb) , weighed 10.9 kg (24 lb) and had a wingspan of 2.24 m (7.3 ft). This specimen is the largest wild goose ever recorded of any species.
The male Canada goose usually weighs 2.6–6.5 kg (5.7–14.3 lb), averaging amongst all subspecies 3.9 kg (8.6 lb). The female looks virtually identical, but is slightly lighter at 2.4–5.5 kg (5.3–12.1 lb), averaging amongst all subspecies 3.6 kg (7.9 lb), and generally 10% smaller in linear dimensions than the male counterparts.
Voice, singing & callThe honk refers to the call of the male Canada goose, while the hrink call refers to the female goose. The calls are similar, however, the hrink is shorter and more high-pitched than the honk of males. When agitated or aggressively defending territory, Canada geese will typically initiate an encounter with a high-pitched hiss. Canada geese communicate with ten different vocalizations, each in response a different situation confronting them.
Distribution & habitatThis species is native to North America. It breeds in Canada and the northern United States in a wide range of habitats. The Great Lakes region maintains a large population of Canada geese. Canada geese occur year-round in the southern part of their breeding range, including the northern half of the United States' eastern seaboard and Pacific Coast, and areas in-between. Between California and South Carolina in the southern United States and in northern Mexico, Canada geese are mainly present as migrants from further north during the winter.
Canada geese have also been introduced in Europe, and had established populations in Great Britain in the middle of the 18th century, Ireland, the Netherlands, Belgium, France, Germany, Scandinavia, and Finland. Most European populations are not migratory, but those in more northerly parts of Sweden and Finland migrate to the North Sea and Baltic coasts.
In recent years, Canada goose populations in some areas have grown substantially, so much so that many consider them pests for their droppings, bacteria in their droppings, noise, and confrontational behavior. This problem is partially due to the removal of natural predators and an abundance of safe, human-made bodies of water near food sources, such as those found on golf courses, in public parks and beaches, on sports fields, and in planned communities. Due in part to the interbreeding of various migratory subspecies with the introduced non-migratory giant subspecies, Canada geese are frequently a year-around feature of such urban environments.
DietCanada geese are primarily 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 beans and grains such as wheat, rice, and corn when they are available. In the water, it feeds from aquatic plants by sliding its bill at the bottom of the body of water. It also feeds on aquatic plant-like algae, such as seaweed.
In urban areas, it is also known to pick food out of garbage bins. They are also sometimes hand-fed a variety of grains and other foods by humans in parks. Canada geese prefer lawn grass in urban areas. They usually graze in open areas with wide clearance to avoid potential predators.
ReproductionDuring 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 dies, the other may find a new mate. The female lays from two to nine eggs with an average of five, and both parents protect the nest while the eggs incubate, but the female spends more time at the nest than the male.
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 incubation period, in which the female incubates while the male remains nearby, lasts for 24–32 days after laying. Canada geese can respond to external climatic factors by adjusting their laying date to spring maximum temperatures, which may benefit their nesting success.
As the annual summer molt also takes place during the breeding season, the adults lose their flight feathers for 20–40 days, regaining flight about the same time as their goslings start to fly.
Chicks, juveniles & raiseAs soon as the goslings hatch, they are immediately capable of walking, swimming, and finding their own food (a diet similar to the adult geese). Parents are often seen leading their goslings in a line, usually with one adult at the front, and the other at the back. While protecting their goslings, parents often violently chase away nearby creatures, from small blackbirds to lone humans who approach: first giving a warning hiss, and then attacking with bites and slaps of the wings. Canada geese are especially protective animals, and will sometimes attack any animal nearing their territory or offspring, including humans. 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 fledgling stage any time from six to nine weeks of age. They do not leave their parents until after the spring migration, when they return to their birthplace.