Canada Goose

The Canada goose (Branta canadensis) is a large wild goose species with a black head and neck, white patches on the face, and a brown body. Native to arctic and temperate regions of North America, its migration occasionally reaches northern Europe. It has been introduced to Britain, New Zealand, Argentina, Chile, and the Falkland Islands. Like most geese, the Canada goose is primarily herbivorous and normally migratory; it tends to be found on or close to fresh water.

Extremely successful at living in human-altered areas, Canada geese have proven able to establish breeding colonies in urban and cultivated areas, which provide food and few natural predators, and are well known as a common park species. Their success has led to them sometimes being considered a pest species because of their depredation of crops and issues with their noise, droppings, aggressive territorial behavior, and habit of begging for food, especially in their introduced range. Canada geese are also among the most commonly hunted waterfowl in North America.

The Canada goose was one of the many species described by Carl 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 Canada goose is also colloquially referred to as the "Canadian goose".

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 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 gray rather than brownish body plumage).

There are seven subspecies of this bird, of widely varying sizes 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. hutchinsii 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 co-mingle with relatively large cackling geese. Of the "true geese" (i.e. the genera Anser or 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 has 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 the 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 exceed 8 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. The female also possesses a different, and less sonorous, honk than the male.