The Canada goose (Branta canadensis) is a large species of 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 France, the United Kingdom, Ireland, Scandinavia, 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.
Adept at living in human-altered areas, Canada geese have established breeding colonies in urban and cultivated habitats, which provide food and have few natural predators. The success of this common park species has led to it often being considered a pest species. This is 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 last is a result of humans not following artificial feeding policies toward wild animals.
Nomenclature and taxonomy
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 gray species of the genus Anser.
Etymology Branta was a Latinized form of Old Norse , "burnt (black) goose" and the specific epithet canadensis is a Neo-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".
Subspecies The AOU has divided the many subspecies between the two species. The subspecies of the Canada goose were listed as: Atlantic Canada goose (B. c. canadensis) (Linnaeus, 1758) Interior Canada goose (B. c. interior) (Todd, 1938) Giant Canada goose (B. c. maxima) (Delacour, 1951) Moffitt's Canada goose (B. c. moffitti) (Aldrich, 1946) Vancouver Canada goose (B. c. fulva) (Delacour, 1951) Dusky Canada goose (B. c. occidentalis) (Baird, 1858) Lesser Canada goose (B. c. parvipes) (Cassin, 1852)
Relation to the cackling goose
The cackling goose was originally considered to be the same species or several subspecies of the Canada goose. But in July 2004, the American Ornithologists' Union's Committee on Classification and Nomenclature split them into two species, making the cackling goose into a full species with the scientific name Branta hutchinsii. The British Ornithologists' Union followed suit in June 2005.
The distinctions between the Canada geese and cackling geese have led to 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 geese" were believed to be a partly hybrid population, with the birds named B. c. taverneri considered a mixture of B. c. minima, B. c. occidentalis, and B. c. parvipes. The holotype specimen of taverneri is a straightforward large pale cackling goose however, and hence the taxon is still valid today and was renamed "Taverner's cackling goose".
In addition, the barnacle goose (B. leucopsis) was determined to be a derivative of the cackling goose lineage, whereas the Hawaiian goose (B. sandvicensis) originated from ancestral Canada geese. Thus, the species' distinctness is well evidenced. Ornithologist Harold C. Hanson, who had rediscovered wild populations of the Giant Canada Goose, proposed splitting Canada and cackling goose into six species and 200 subspecies. The radical nature of this proposal has been controversial; Richard Banks of the AOU urges caution before any of Hanson's proposals are accepted. The International Code of Zoological Nomenclature has suppressed Hanson's proposals, based on the criticisms of Banks and other ornithologists.
Description
The black head and neck with a white "chinstrap" distinguish the Canada goose from all other goose species except the cackling goose and barnacle goose. (The latter, however, has a black breast and gray rather than brownish body plumage.) Some Canada geese come with a pepper-spotted or brown neck with brown plumage, and these are assumed to be a leucistic variety. On occasion, individuals with dark cheeks, white foreheads or white necks may be seen
The seven subspecies of this bird vary widely in size and plumage details but all are recognizable as Canada geese. Some of the smaller subspecies 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 in length and have a wingspan. Among standard measurements, the wing chord can range from , the tarsus can range from and the bill can range from . 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 subspecies B. c. maxima, which rarely exceed , weighed and had a wingspan of . This specimen is the largest wild goose ever recorded of any species.
The male Canada goose usually weighs , averaging amongst all subspecies . The female looks virtually identical but is slightly lighter at , averaging amongst all subspecies , and generally 10% smaller in linear dimensions than the male counterparts. The honk refers to the call of the male Canada goose, whilst the call refers to the female goose. The calls are similar but the is shorter and higher 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 to a different situation confronting them.
Distribution and habitat
This 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 live 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.
By the early 20th century, overhunting and loss of habitat in the late 19th and early 20th centuries 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.
In 1964, the Northern Prairie Wildlife Research Center was built near Jamestown, North Dakota. Its first director, Harvey K. Nelson, talked Forrest Lee into leaving Minnesota to head the center's Canada goose production and restoration program. Forrest soon had 64 pens with 64 breeding pairs of screened, high-quality birds. The project involved private, state, and federal resources and relied on the expertise and cooperation of many individuals. By the end of 1981, more than 6,000 giant Canada geese had been released at 83 sites in 26 counties in North Dakota.
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-round feature of such urban environments.
Contrary to its normal migration routine, large flocks of Canada geese have established permanent residence along the Pacific coast of North America from British Columbia's Lower Mainland and Vancouver Island area south to the San Francisco Bay area of Northern California. There are also resident Atlantic coast populations, such as on Chesapeake Bay, in Virginia's James River regions, and in the Triangle area of North Carolina (Raleigh, Durham, Chapel Hill), and nearby Hillsborough. Some Canada geese have taken up permanent residence as far south as Florida, in places such as retention ponds in apartment complexes.
In 2015, the Ohio population of Canada geese was reported as roughly 130,000, with the number likely to continue increasing. Many of the geese, previously migratory, reportedly had become native, remaining in the state even in the summer. The increase was attributed to a lack of natural predators, an abundance of water, and plentiful grass in manicured lawns in urban areas. Canada geese were eliminated in Ohio following the American Civil War but were reintroduced in 1956 with 10 pairs. The population was estimated at 18,000 in 1979. The geese are considered protected, though a hunting season is allowed in September. The Ohio Department of Natural Resources recommends several non-lethal scare and hazing tactics for nuisance geese, but if such methods have been used without success, they may issue a permit to destroy nests, conduct a goose roundup or exterminate geese.
Outside North America
Eurasia
Canada geese have reached Northern Europe naturally, which has been confirmed by ringing recoveries. The birds include those of the subspecies B. c. parvipes, and possibly others. These geese are also found naturally on the Kamchatka Peninsula in eastern Siberia, and eastern China.
Canada geese were also introduced into Europe in the early 17th century by explorer Samuel de Champlain, who sent several pairs to France as a present for King Louis XIII. The geese were introduced into Great Britain in the late 17th century as an addition to King James II's waterfowl collection in St James's Park. By the middle of the 18th century Canada geese had established populations in France and Great BritainAttenborough, D. 1998. The Life of Birds. p.299 BBC. and also in Ireland. They were also introduced into the Netherlands, Belgium, Germany, Scandinavia, and Finland in the 20th Century, starting in Sweden in 1929. Most European populations are not migratory but those in more northerly parts of Sweden and Finland migrate to the North Sea and Baltic coasts.