Canada Goose

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 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+1⁄2 to 21+1⁄2 in), the tarsus can range from 6.9 to 10.6 cm (2+11⁄16 to 4+3⁄16 in) and the bill can range from 4.1 to 6.8 cm (1+5⁄8 to 2+11⁄16 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 subspecies 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 ft 4 in). This specimen is the largest wild goose ever recorded of any species. The male Canada goose usually weighs 2.6–6.5 kg (5+3⁄4–14+1⁄4 lb), averaging amongst all subspecies 3.9 kg (8+1⁄2 lb). The female looks virtually identical but is slightly lighter at 2.4–5.5 kg (5+1⁄4–12+1⁄4 lb), averaging amongst all subspecies 3.6 kg (8 lb), and generally 10% smaller in linear dimensions than the male counterparts. The honk refers to the call of the male Canada goose, whilst the hrink call refers to the female goose. The calls are similar but the hrink 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.

Range & 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.

Behaviour

Like 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 a 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 southwestern British Columbia to California to the Great Lakes, some of the population has become nonmigratory due to adequate winter food supply and a lack of former predators. Males exhibit agonistic behavior both on and off breeding and nesting grounds. This behavior rarely involves interspecific killing. One documented case involved a male defending his nest from a brant that wandered into the area; the following attack lasted for one hour until the death of the brant. The cause of death was suffocation or drowning in mud as a direct result of the Canada goose's pecking the head of the brant into the mud. Researchers attributed it to high hormone levels and the brant's inability to leave the nesting area.

Adapted from Canada goose on Wikipedia, used under CC BY-SA 4.0.