Canada goose

Name and taxonomy

Carl Linnaeus described the Canada goose in the 18th century. The genus name Branta comes from an Old Norse word meaning a burnt or blackened goose. The second name, canadensis, is Latin for a bird from Canada. The Oxford English Dictionary traces the English name back to 1772. Many people say Canadian goose, but that form has never been the standard one.

Seven subspecies are recognised, and they differ in size and in plumage detail. The giant Canada goose is the largest, and the lesser Canada goose is the smallest. In 2004 American ornithologists split the smaller forms off as the cackling goose. British ornithologists accepted that split in 2005. One researcher later proposed six species and 200 subspecies for the group. The nomenclature commission set that proposal aside after strong criticism.

Evolution and relatives

Branta holds the black geese, and Anser holds the grey ones. The Canada goose sits close to the cackling goose, which was long treated as the same bird. The barnacle goose grew out of the cackling goose line. The Hawaiian goose, by contrast, descends from ancestral Canada geese.

Barnacle geese share the black neck but have a black breast and grey body. Small Canada geese and large cackling geese overlap in weight and confuse observers. A cackling goose has a shorter neck and a smaller bill, which helps. Canada geese hybridise with greylag, snow and barnacle geese in captivity. Wild crosses are rarer, and adoption of stray chicks may explain some of them.

Appearance

The black head and neck with the white chinstrap identify the bird at a glance. Only the cackling goose and the barnacle goose share that pattern. Back and wings are shades of brown and grey, and the belly and rump are pale. Length runs 75 to 110 cm, and the wings span 127 to 185 cm. Males weigh 2.6 to 6.5 kg and females 2.4 to 5.5 kg.

A female is otherwise almost identical, about a tenth smaller in her measurements. One giant Canada goose weighed 10.9 kg and spanned 224 cm across the wings. That bird remains the heaviest wild goose ever recorded. The bill carries comb-like ridges along the edge, which grip and cut grass. Goslings hatch yellow, with grey-green down on the back and a black bill and feet. Some adults show a speckled brown neck, and these are probably leucistic birds.

Habitat and range

The species breeds across Canada and the northern United States. The Great Lakes hold a very large share of the total. Birds from the far north winter as far south as northern Mexico. Along both American coasts many flocks now stay put all year. The birds want open grassy ground with a clear view and water close by. They avoid tall grass and scrub, which can hide an approaching predator.

Some geese cross the Atlantic on their own, and ringing has proved it. The bird also occurs naturally in Kamchatka and eastern China. Samuel de Champlain sent pairs to France as a gift for King Louis XIII. Birds reached England in the late 17th century for the royal collection in St James's Park. Sweden received its first birds in 1929, and New Zealand in 1905.

The British population suggests how fast the bird can spread. Surveys in 1953 counted somewhere between 2,670 and 10,090 birds. The estimate reached 82,000 in 1999 and 165,000 wintering birds in 2017. Reservoirs, flooded gravel pits and farm change all helped. Moving breeding pairs away from farmland in the 1950s only founded new colonies.

Diet and feeding

The bird lives mostly on plants, and grass is the staple. It grips a blade in the bill and tears it free with a jerk of the head. The ridges along the bill edge do the cutting. Sedges, leaves, roots, seeds and berries all go the same way. On water the goose sifts plants from the bottom and takes algae and seaweed.

Wheat, rice, corn and beans are taken from fields wherever they grow. Animal food is a minor part: some insects, small fish, snails and crustaceans. Geese eat more of it while breeding and while rearing young. Plants loaded with bitter compounds are left alone. A goose can go about 30 days without food if conditions turn bad. In towns the birds prefer mown lawn, and some raid bins or beg from people.

Behaviour and social life

Canada geese live in flocks outside the breeding season. They fly in the familiar V, which saves energy for the birds behind. The lead bird works hardest, so the flock swaps that position around. A flock can cover up to 2,400 kilometres in one day of flying. Migrating birds usually travel about 1 km above the ground. One report puts geese at 9 km, though the true ceiling is unknown.

Autumn passage runs from September into early November. Early migrants rest less and move faster than the birds that follow. Many pairs come back to the same patch of nesting ground each spring. Ganders are aggressive on and off the breeding ground. In one recorded case a gander killed a brant that strayed onto his territory. Families with goslings often merge into a group called a creche.

Communication and senses

Ten different calls have been described for the species. The deep honk belongs to the gander. The female answers with a shorter, higher note. Flocks call constantly in flight, which probably keeps the formation together.

A threatened goose starts with a hard hiss. It then stands tall and spreads its wings to look larger. If that fails the bird charges, pecks and beats with the wings. Sight appears to matter most, because the birds graze where they can see far. Goslings recognise their parents' voices and follow them in a line.

Reproduction and life cycle

Geese find a mate in their second year. Pairs match up by size, and most stay together for the rest of their lives. A bird whose partner dies will usually take another. First breeding often waits until the third year. The pair breeds once a season, from April into May, later in cold country.

The female chooses the site, on raised dry ground with water and a view. She scrapes a hollow, lines it with plants and adds down from her own breast. Beaver lodges and small islands are both popular. She lays 2 to 9 eggs, about 5 on average, one every day and a half. Incubation lasts 24 to 32 days and falls mainly to her, with the gander on guard.

Goslings can walk, swim and feed themselves within a day of hatching. The parents lead them in a line, one in front and one behind. Adults moult during this period and cannot fly for 20 to 40 days. The young fly at six to nine weeks, about the time their parents get their wings back. Families stay together until the spring migration ends. Wild geese that reach adulthood live 10 to 24 years, and one female reached 33.

Predators and threats

Eggs and goslings are the vulnerable stage. Coyotes, red foxes, Arctic foxes, raccoons and bears all raid nests. Large gulls, ravens and crows take eggs and small young. In Europe the mink, the otter and the mute swan add to the list. Loose dogs kill geese in parks, which a lead would prevent.

Healthy adults are probably large enough to deter most hunters. Bald eagles, golden eagles and snowy owls can still kill a grown bird. The gander normally leads the defence and tries to draw a predator away. Disease is a real risk, including avian influenza, botulism and avian cholera. Salt water kills young goslings before their salt glands start working. People kill far more Canada geese than any other predator does.

Population and conservation

The IUCN lists the Canada goose as Least Concern. Around 2000 the North American total was put at 4 million to 5 million birds. The picture was very different a century ago. Hunting and habitat loss cut the species hard by the early 20th century. The giant subspecies was thought extinct until a flock turned up in Minnesota in 1962.

A breeding programme in North Dakota released more than 6,000 giant Canada geese. Restored birds, safe ponds and few predators then drove numbers up sharply. Ohio counted about 130,000 geese in 2015, up from 18,000 in 1979. The United States has run lethal culls in built-up areas since 1999. Managers also shake or oil eggs, which stops a clutch without killing adults. The bird still keeps legal protection outside the open season on both sides of the border.

Relationship with humans

The Canada goose is a game bird across its native range. The American harvest for one recent season passed 1.3 million birds. Opinions on the meat differ sharply between countries. Down from the plumage goes into coats, pillows and bedding. The birds are rarely farmed, and wild meat is hard to sell legally.

Where flocks settle in parks the complaints are droppings, noise and aggression. Grazing packs the soil and thins the grass on playing fields and greens. Droppings feed algae in ponds and raise bacteria counts on beaches. Aircraft strikes are the most serious problem of all. American authorities logged 1,772 civil strikes between 1990 and 2018. A military aircraft hit a flock in Alaska in 1995 and crashed, killing 24 crew. In 2009 geese stopped both engines of an airliner that then landed on the Hudson.

In culture and myth

Canadians treat the goose as one emblem of the country itself. Its shape and its call appear on badges, coins and company names. For many people in North America the V overhead marks the change of season. That association works in both directions, spring and autumn.

European aristocrats first kept the bird as an ornament. A French king and an English king both received geese as gifts. British estates stocked them as decoration and as something to shoot. New Zealand imported them purely as game in 1905. In each case the ornament probably outgrew the garden that held it.

The pair bond appears to have given the bird a reputation for loyalty. Writers may use the goose as a symbol of a mate kept for life. The Hudson River landing of 2009 probably fixed a darker image alongside it. Both readings rest on real behaviour: strong pair bonds and heavy flocks.