A chemical called methiocarb is being used on grass to prevent geese from grazing on it in some areas. Methiocarb makes the geese feel sick, but thus far has not resulted in any deaths. The toxic effects of this chemical are still being researched. Over 200 geese have been killed by the chemical parathion in Texas. Golden eagles and bald eagles have been seen eating the bodies of geese that have been killed by parathion which means it could potentially be very dangerous for them as well.
Canada geese have good eyesight, which is necessary for flight. They must move their heads in order to see all the way around themselves. However, their eyes are close to their crowns on the side of their heads, enabling them to see more than 180 degrees (closer to 270 degrees) horizontally and vertically. They have mostly monocular vision. Canada geese have excellent hearing and the ears are located on the side of its head. Canada geese often use body movements to communicate with each other. These geese also have the ability to make at least 10 different calls
Communication Channels: visual ; tactile ; acoustic
Perception Channels: visual ; tactile ; acoustic ; chemical
In 1918 when the Migratory Bird Treaty was passed, spring shooting was prohibited in the United States and Canada. This regulated the hunting season to three and a half months of the year. The hunting regulations currently in place are for shooting season limits and bag limits in relation to the amount of birds currently in the population. A quota system was put in place in 1960 to regulate the number of geese shot in a given year.
One subspecies, Aleutian-Canadian Geese, were listed as endangered by the U.S. Fish and Wildlife Service in 1967. This was due to the introduction of a non-native arctic fox species to their nesting islands. They became predatory on the naturally defenseless geese. This introduction caused the population to decline to approximately 800 individuals. However, in 1990, due to increasing numbers, the U.S. Fish and Wildlife Service changed the listing to threatened. The state of Alaska also changed the species listing from endangered to a species of special concern. Aleutian-Canadian Geese are now recorded around 15,000 individuals and nesting on eight islands.
On the other hand, some populations have grown so numerous, there are many organizations who are trying to regulate the populations of these geese. They see this as necessary because if the goose population continues to rise at its current rate, they will present a very serious problem to their surrounding environment in only a few years. Other organizations believe that the methods and ideas of these organizations are cruel and unnecessary. These groups believe that the growing population is not nearly as threatening as some believe and that they are actually at great risk because of the excessive hunting and death by pesticides that geese populations experience.
US Migratory Bird Act: protected
US Federal List: threatened
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
Canada geese can become a nuisance, especially when normally migratory birds become resident. They can overgraze lawns and crops, leading to erosion. On lawns, their feces can annoy humans. Build-up of fecal matter can lead to reduced water quality, by fostering bacteria and adding much nitrogen and phosphorus.
Canada geese can be an exceptional annoyance in Atlantic flyway states by crowding in on golf courses, beaches, parks, playing fields, and yards. In the eastern states, Canada Geese have been very harmful to local crops and have forced farmers to plant a lot more winter wheat to compensate for the damage done by these geese.
Negative Impacts: crop pest
Canada Geese have been hunted by humans for hundreds of years. Native Americans hunted them in the spring migration. Eskimos hunted them by taking advantage of the molt that leaves them flightless. Even early white settlers took advantage of these birds and hunted them for food. These birds are still being hunted today in the United States and Canada.
Positive Impacts: food ; body parts are source of valuable material
As well as dispersing the seeds of the plants they eat, Canada Geese are important prey for many predators in the ecosystems in which they live.
Ecosystem Impact: disperses seeds
When on land, Branta canadensis eat a variety of grasses including Bermuda grass, salt grass and wild barley. Geese are able to grab a hold of each blade and pull it out with their bills by jerking their heads. They also eat wheat, beans, rice, and corn. In the water, the birds stick their head and upper part of their body into the water leaving their tail and back end extending in the air. They stretch their neck out, under the water, and slide their bills across the bottom silt. They also eat a number of aquatic plants such as eel grass, sea lettuce and sago.
Plant Foods: leaves; roots and tubers; seeds, grains, and nuts; algae
Primary Diet: herbivore (Folivore )
Canada Geese are found throughout North America. There are four subspecies (or populations); each is found in a different area of North America. These subspecies are the southern, northern, western and Aleutian-Canadian populations. The southern population ranges from 60 degrees north latitude to the Rockies and Atlantic Ocean. The northern population ranges north of 60 degrees north latitude in the Arctic and Subarctic. Canada geese travel to the southern parts of the United States during the winter. The western population is found along the coasts of Alaska and British Columbia. The Aleutian-Canadian population is rarely found. A general trend in all subspecies is that they they spend summers in the northern parts of North America, especially Canada, and migrate south to areas of the United States in the winter months.
Biogeographic Regions: nearctic (Native )
Canada Geese are found near waterways in open, grassy habitats such as grasslands, chaparral, and arctic tundra. They also inhabit man-made habitats that are open and grassy, such as golf courses, agricultural land, airports, and parks.
Habitat Regions: temperate ; terrestrial ; freshwater
Terrestrial Biomes: tundra ; savanna or grassland
Aquatic Biomes: lakes and ponds; rivers and streams; coastal
Wetlands: marsh
Other Habitat Features: suburban ; agricultural ; riparian
It is not clear exactly how long the average Canada goose can live, but there have been two geese that were reported to have lived very long lives. One of them lived to be 24 years old and another reached 23. In captivity, two geese were reported to live to 42 years old. Probably most Canada geese die within their first year of life, as nestlings, fledglings, and during their first migration.
Range lifespan
Status: wild: 24 (high) years.
Range lifespan
Status: captivity: 42 (high) years.
Average lifespan
Status: wild: 364 months.
Branta canadensis individuals have a black neck, bill, and head with a white strap under the chin and occasional white patches elsewhere. The body is usually brownish-gray although colors vary in some of the subspecies. In some of the smaller subspecies the body is dark brown in color where as in some of the larger subspecies, the body is a light gray tone. Underneath, the colors are much lighter and almost white on the tail. During flight the tail shows a white semi-circle just above the black tail. Females may be slightly smaller than males, although both are similar to each other in color pattern. The bill of Branta canadensis tapers from the base where it is high to the end where it has narrowed. The bill has lamellae, or teeth around the outside that are a used as a cutting tool. The legs are close together with very black feet. These geese have very large wings (127 to 173 cm wingspan) that can also be used as weapons. The weight of Branta canadensis varies depending on the subspecies.
Goslings (young Canada geese) are yellow with some greenish-gray colorings on top of their heads and backs. As with the adult color pattern, there is some variation among the different subspecies. Goslings of the darker subspecies have a brownish olive or blunt yellow coloring while those of the lighter subspecies are lighter and brighter in color. These colors fade as the gosling grows into the adult color pattern. All goslings have black or blue-gray bills and legs that become darker as they age.
Range mass: 1100 to 8000 g.
Range length: 90 to 200 cm.
Range wingspan: 127 to 173 cm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger
Unguarded nests and eggs are targets for predators such as gulls, common ravens, American crows, skunks, domestic dogs, and many others. Males send out an alarm by flying into the air and honking as a predator approaches. This alerts not only his mate but others nesting nearby. Females lower their bodies onto the nest and stretch out their necks to camouflage the nest.
Canada geese are also a common game bird, hunted regularly by humans.
Known Predators:
Canada geese are monogamous. Pairs form during the winter, during migration or on their wintering grounds, for the next breeding season. Mated pairs may stay together for more than one year, sometimes staying together for life.
Males fight over females with their wings and bills. The winner approaches the female with his head down and neck undulating. He makes hissing and honking noises. The pairs mate either before or after they have found a nesting location. Mating, occurs in the spring on the water. The female is usually partially submerged or completed submerged while copulation takes place.
Mating System: monogamous
The average clutch size is five eggs, although this size ranges from 2 to 9 eggs. The incubation period lasts 23 to 30 days.
Females incubate the eggs, choose the location for nesting, and even build the nest without males. Males defend the territory, nest, and eggs from intruders, such as other geese. Female Canada geese pick nesting sites that are isolated but have good visibility. This allows them to readily see danger approaching and to be difficult to get at. The nesting area also must have open water with low banks so they can have access to water plants and places to get into or out of the water. Swamps, marshes, meadows, lakes, and other such areas are among some of their favorite nesting spots. The Canadian and Alaskan shorelines have expanses of tundra habitat that provide good nesting sites. Canada geese are often seen nesting on small islands that don't have very tall grasses or on muskrat houses (which are similar to small islands).
Nests are very simple and are made quickly. Materials that are used are weeds, twigs, grass, moss, needles, and other such materials. After some collection and building, female geese round out a curve or depression with their bodies. They drop the materials around themselves and move the items to get the best fit. From time to time they round out the center with their chests or feet. If there are no items of vegetation the nest may only be a depression in the ground shaped by their chests and feet. Once the eggs are laid, the nest is lined with feathers and down. Down insulates against extreme warmth as well as cold, stabilizing egg temperature.
Incubation must occur immediately after the last eggs are laid. The incubation period lasts 23 to 30 days. The female turns the eggs regularly to promote proper development and changes their position in the nest to maintain even incubation temperatures. The offspring hatches via an egg tooth on top of its beak to crack open the shell. Goslings keep cracking open the shells until they are completely free between 24 and 48 hours later. All of the eggs in the clutch are fully hatched within 24 hours. Goslings within a clutch usually have a sex ratio of 1:1. Hatchlings fledge in 68 to 78 days after hatching.
Breeding interval: Canada geese breed once yearly.
Breeding season: Females start laying eggs during the first weeks of March and continue as late as June in parts of the Arctic.
Range eggs per season: 2 to 9.
Average eggs per season: 5.
Range time to hatching: 23 to 30 days.
Range fledging age: 68 to 78 days.
Average age at sexual or reproductive maturity (female): 1 years.
Average age at sexual or reproductive maturity (male): 1 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous
Average eggs per season: 5.
After the eggs hatch, the family group (the offspring and parents) leave the nest and begin to travel together to feed and seek shelter. Both males and females feed and guard their young. Upon hatching, young Canada geese are able to follow their parents around and leave the nest.
Parental Investment: precocial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Male, Female, Protecting: Male, Female); pre-independence (Provisioning: Male, Female, Protecting: Male, Female)
