Emperor goose | |
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An adult emperor goose | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Anseriformes |
Family: | Anatidae |
Genus: | Anser |
Species: | A. canagicus |
Binomial name | |
Anser canagicus (Sevastianov, 1802) | |
Synonyms [3] | |
The emperor goose (Anser canagicus), also known as the beach goose [6] or the painted goose, [7] is a waterfowl species in the family Anatidae, which contains the ducks, geese, and swans. In summer, the emperor goose is found in remote coastal areas near the Bering Sea in arctic and sub-arctic Alaska and the Russian Far East, where it breeds in monogamous pairs. It migrates south to winter in ice-free mudflats and coasts in Alaska, mostly the Aleutian Islands, and Canada's British Columbia, rarely reaching the contiguous United States. Listed as near threatened by the International Union for Conservation of Nature, the species' population is declining due to threats such as pollution, hunting, and climate change. [1]
The emperor goose was described in 1802 as Anas canagica. Its type locality is Kanaga Island, which is located in the Aleutian Islands, Alaska. The species has sometimes been classified in the genus Chen and less commonly in its own genus, Philacte. [8]
The emperor goose has a stout blue-gray body, [6] with spots of black and white, which cause it to have a "scaled appearance". [9] Its head and the back of its neck are white and tinged with amber-yellow; [7] unlike the snow goose, the white does not extend to the front of the neck.
The goose is also characterized by a black chin and throat, a white tail, a pink bill, which is tipped with white, and yellow-orange legs and feet. [7] [10] The underside of the emperor goose's wings is gray, unlike the snow goose, which has black and white on the underside of its wings. The head of adults frequently turns to a reddish-brown color in summer, due to its feeding in tidal pools with iron oxide. [10]
Goslings (i.e. young shortly after hatching) are grayish-white colored; unlike adults, their bill is black. Goslings are also distinguished from adults by having gray, brown, or black feet and an area of white surrounding the bill for the first three weeks after hatching.
Juveniles (i.e. immature specimens older than goslings) are mostly gray colored, with a small amount of white on their feathers. Younger juveniles have a dark head and neck, [10] with their head being dusty-colored with patches of white. [7] However, after October, their head and upper neck turn to mostly white, although they still have scattered darker feathers. By the first winter, juveniles have the same coloring and features as adults. [10]
Adult males grow to a total length of 26–28 inches (66–71 cm) and females 25.6–27.5 inches (65–70 cm).
Other measurements in males, sampled from four specimens in Alaska and California, include a 2.5–2.98-inch (6.4–7.6 cm) tarsus (lower leg), a 1.42–1.6-inch (3.6–4.1 cm) bill, and a 13.5–15.5-inch (34–39 cm) folded wing. These measurements are similar in females, but females have a slightly shorter folded wing of 14.75–15.45 inches (37.5–39.2 cm) based on two Alaskan individuals. [11] The goose has a wingspan of 119 centimetres (47 in). [8] Because of its short wings, it flies slowly, requiring quick strokes. [10]
Males weigh between 2.766 kilograms (6.10 lb) and 3.129 kilograms (6.90 lb). They have a mean weight of 2.316 kilograms (5.11 lb), while females have a mean weight of 1.945 kilograms (4.29 lb). [8] The average weight of juveniles is 1.165 kilograms (2.57 lb) in males and 1.107 kilograms (2.44 lb) in females. Roughly 5–7.5 weeks after hatching, the goose averages a weight of 2.370 kilograms (5.22 lb) and 1.926 kilograms (4.25 lb) in males and females, respectively. [10] It has a heavy body and short neck compared to other geese. [12] Although the species can live to age 25 in captivity, it reaches age 12 in the wild. [13]
The emperor goose is migratory, traveling north in the summer to breed and south for the winter. [14] Unlike many goose species, which migrate thousands of miles, the emperor goose travels a few hundred miles for migration, [15] usually about 370 miles (600 km) to 470 miles (760 km). [8] Breeding birds molt near the breeding colonies, but geese unsuccessful with breeding move to either St. Lawrence Island or the Chukchi Peninsula to molt prior to the main southerly migration for winter. [16]
The breeding season starts in late June in Russia, but begins a few weeks earlier in Alaska, generally between 20 May and 3 June. [8] Only individuals three years or older will mate. A monogamous species, female emperor geese have a single mate throughout their life and only mate with any other male if their mate dies. [13] The species molts from late July to early August and leaves its breeding grounds later than any other species. [11]
The emperor goose breeds on tundra, building its nests in areas 10 miles (16 km) or closer to the coast. [14] The nests are typically constructed in marshes. [11] They are built as holes in the ground without containing nesting material, but are later built up with vegetation, such as leaves, [7] and feathers, which the female plucks from herself. [11]
The species usually lays 4–6 eggs, but it can lay anywhere from 2 to 8; eggs are often laid in the nests of other emperor geese families. [14] Eggs measure 7.86 centimetres (3.09 in) by 5.21 centimetres (2.05 in) on average, with an elliptical shape and a smooth shell. They are initially white colored, but become speckled with stains from their nest. [12] Egg incubation, usually lasting 24 days, is performed only by females. [14]
According to The Game Birds of California, a 1918 book, surveys of the species' nests showed that the male did not stay with the nest. However, the Beardsley Zoo says that although the male does not help build the nest, it defends it. The eggs hatch in late June and early July. [11] Exhibiting precociality, young are able to walk and swim hours after hatching, [14] as well as feed themselves. They typically vacate the nest the same day as their hatching, although they do not wander far from their parents until after two months. [13] Young can fly once 50−60 days old. [14] 10% of emperor geese remain alive after their first year. [13]
Individuals of the species usually only interact with their family; however, larger flocks collect during the breeding season and the molting season. [13] It is one of the most unsocial goose species; the only goose less social than it is the black brant. [11] It stays low when flying, usually keeping below 90 feet (27 m) above the ground and often coming close to touching the ground with its wings. [12]
In the summer, the species' diet consists of vegetation, such as shoots, roots, and berries, while in the winter it primarily eats bivalve molluscs (which it uses its sense of touch to catch) [13] and algae. [14]
Unlike other goose species, [10] its diet mostly consists of animals, [12] causing its flesh to have a strong flavor. [12] When living near water, it eats at the edge of water bodies, which has given it the name "Beach Goose". [6] If the species feels threatened, it goes into a body of water and swims away until the threat is a safe distance from it. [13]
Its vocalizations, according to Edward William Nelson, sound like "kla-ha, kla-ha, kla-ha", [12] and can be differentiated from those of other geese by having a more "nasal" sound. [8] It vocalizes less often than other geese, such as the white-fronted goose. [12]
During the summer, the emperor goose lives in Arctic and subarctic climates in the Bering Sea, around Alaska and a small part of northeast Russia. [17] Its habitats in this season include freshwater pools, inland lakes, and coastal lagoons. [13] 90% of specimens nest on the Yukon-Kuskokwim Delta. [15] In the winter, after its southerly migration, it lives primarily among the Aleutian Islands, [1] as well as on the Alaska Peninsula and the Kodiak Island. [15] It sometimes spends winters in Canada [1] and rarely as far south as northwestern California. Some areas in California the species has been found living in, as of 1918, include Humboldt Bay, Gridley, Davis, Rio Vista, Colusa County, Ingomar, Modesto, and Dixon. [11] Its habitats are mudflats and rocky shores in the winter, [14] in areas free of ice, [17] and tundra wetlands in the summer. [9] Its extent of occurrence is estimated to be 775,000 square kilometres (299,000 sq mi). [1]
As of August 2017, the emperor goose's population is increasing slowly. [18] In 1879, the emperor goose was found by Edward William Nelson to be abundant along the Yukon-Kuskokwim Delta.
In 1923, however, Arthur Cleveland Bent observed much fewer specimens, and reported that the population had decreased over the past 30 years prior to that. Bent said that "large numbers are killed each year and their eggs taken by the natives, even within the limits of what is supposed to be a reservation", which was a major reason for the goose's decrease in population. [12] In 1964, the goose's population was 139,000, which decreased to 42,000 in 1986.
The population subsequently increased, [6] with its population having been 85,000 in 2002 and over 98,000 in 2015; [19] According to the emperor goose's entry on the Red List of the International Union for Conservation of Nature (IUCN), which was entered on 1 October 2016, the total population of the emperor goose is decreasing.
However, it also said that the trend is not clear and it is increasing in parts of North America. [1] Julian Fischer, a wildlife biologist, said in a news article published in August 2017, that the population has been experiencing a slow, steady increase.
He stated that the population had over doubled in size from the early 1980s, and that it may be as large as 170,000. [18]
Although the reasons for the emperor goose's population decline are not well known, it is believed to be threatened by oil pollution, hunting, and climate change. [1]
Other factors contributing to the species' population decline include competing with the cackling goose for food and the preying of goslings. [10] The emperor goose is listed as near threatened on the IUCN Red List [1] and rated 14 out of 20 on the Continental Concern Score. The 2016 State of North America's Birds' Watch List, a list of threatened birds that have no major conservation actions taking place for them, includes the emperor goose. [19]
Due to its low population in the 1980s, recreational and subsistence hunts closed for the goose in 1986 and 1987, respectively. However, 30 years later, hunts became legal again after the population grew significantly. In 2015, the Alaska Migratory Bird Co-Management Council suggested for hunting of the bird to be allowed if the population were to grow to a certain number. On 2 April 2017, subsistence hunting was allowed for the emperor goose, with hunters able to kill an unlimited number of geese. In fall 2017, emperor geese were allowed to be hunted for recreational purposes by locals of Alaska with a permit, with a limit of one bird per person.
In 2018, hunters who were not residing in Alaska were permitted to hunt the geese with a permit. However, the species cannot be hunted anywhere in the contiguous United States. [15] [18]
A goose is a bird of any of several waterfowl species in the family Anatidae. This group comprises the genera Anser and Branta. Some other birds, mostly related to the shelducks, have "goose" as part of their names. More distantly related members of the family Anatidae are swans, most of which are larger than true geese, and ducks, which are smaller.
The nene, also known as the nēnē or the Hawaiian goose, is a species of bird endemic to the Hawaiian Islands. The nene is exclusively found in the wild on the islands of Oahu, Maui, Kauaʻi, Molokai, and Hawaiʻi. In 1957, it was designated as the official state bird of the state of Hawaiʻi.
The greylag goose or graylag goose is a species of large goose in the waterfowl family Anatidae and the type species of the genus Anser. It has mottled and barred grey and white plumage and an orange beak and pink legs. A large bird, it measures between 74 and 91 centimetres in length, with an average weight of 3.3 kilograms. Its distribution is widespread, with birds from the north of its range in Europe and Asia often migrating southwards to spend the winter in warmer places, although many population are resident, even in the north. It is the ancestor of most breeds of domestic goose, having been domesticated at least as early as 1360 BCE. The genus name is from anser, the Latin for "goose".
The greater white-fronted goose is a species of goose that is closely related to the smaller lesser white-fronted goose. The greater white-fronted goose is migratory, breeding in northern Canada, Alaska, Greenland and Russia, and winters farther south in North America, Europe and Asia. It is named for the patch of white feathers bordering the base of its bill: albifrons comes from the Latin albus "white" and frons "forehead". In the United Kingdom and Ireland, it has been known as the white-fronted goose; in North America it is known as the greater white-fronted goose, and this name is also increasingly adopted internationally. Even more distinctive are the salt-and-pepper markings on the breast of adult birds, which is why the goose is colloquially called the "specklebelly" in North America.
The pink-footed goose is a goose which breeds in eastern Greenland, Iceland, Svalbard, and recently Novaya Zemlya. It is migratory, wintering in northwest Europe, especially Ireland, Great Britain, the Netherlands, and western Denmark. The name is often abbreviated in colloquial usage to "pinkfoot". Anser is the Latin for "goose", and brachyrhynchus comes from the ancient Greek brachus "short" and rhunchos "bill".
The snow goose is a species of goose native to North America. Both white and dark morphs exist, the latter often known as blue goose. Its name derives from the typically white plumage. The species was previously placed in the genus Chen, but is now typically included in the "gray goose" genus Anser.
The barnacle goose is a species of goose that belongs to the genus Branta of black geese, which contains species with largely black plumage, distinguishing them from the grey Anser species. Despite its superficial similarity to the brant goose, genetic analysis has shown it is an eastern derivative of the cackling goose lineage.
The Canada goose, sometimes called Canadian goose, is a large wild 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, Finland, Sweden, Denmark, 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.
The surf scoter is a large sea duck native to North America. Adult males are almost entirely black with characteristic white patches on the forehead and the nape and adult females are slightly smaller and browner. Surf scoters breed in Northern Canada and Alaska and winter along the Pacific and Atlantic coasts of North America. Those diving ducks mainly feed on benthic invertebrates, mussels representing an important part of their diet.
Steller's eider is a migrating Arctic diving duck that breeds along the coastlines of eastern Russia and Alaska. It is the rarest, smallest, and fastest flying of the eider species.
The swan goose is a large goose with a natural breeding range in inland Mongolia, Northeast China, and the Russian Far East. It is migratory and winters mainly in central and eastern China. Vagrant birds are encountered in Japan and Korea, and more rarely in Kazakhstan, Laos, coastal Siberia, Taiwan, Thailand and Uzbekistan.
Ross's goose is a white goose with black wingtips and a relatively short neck. It is the smallest of the three white geese that breed in North America. It is similar in appearance to a white-phase snow goose, but about 40% smaller. Other differences from the snow goose are that the bill is smaller in proportion to its body and lacks "black lips". The dark phase is extremely rare.
The spectacled eider is a large sea duck that breeds on the coasts of Alaska and northeastern Siberia.
The kelp goose is a species of waterfowl in tribe Tadornini of subfamily Anserinae. It is found in Argentina, Chile, and the Falkland Islands.
The cackling goose is a species of goose found in North America and East Asia.
A domestic goose is a goose that humans have domesticated and kept for their meat, eggs, or down feathers. Domestic geese have been derived through selective breeding from the wild greylag goose and swan goose.
Anser is a waterfowl genus that includes the grey geese and the white geese. It belongs to the true goose and swan subfamily of Anserinae under the family of Anatidae. The genus has a Holarctic distribution, with at least one species breeding in any open, wet habitats in the subarctic and cool temperate regions of the Northern Hemisphere in summer. Some also breed farther south, reaching into warm temperate regions. They mostly migrate south in winter, typically to regions in the temperate zone between the January 0 °C (32 °F) and 5 °C (41 °F) isotherms.
Pilgrim geese is a breed of domestic goose. They are considered to be a relatively quiet, lightweight and medium-sized breed. The pilgrim goose is a rare and critically endangered species according to the American Livestock Breeds Conservancy (ALBC) and was officially entered into the American Poultry Association's Standard of Perfection in 1939. Generally, they can live for 15 to 25 years. In most breeds of geese, males and females are indistinguishable from one another; however, the pilgrim goose is well known for its auto-sexing trait. Males are characterised by white feathers while the females have grey. This sexual dimorphism makes pilgrim geese desirable for breeding as the sexes are easily determined. Their commercial use is primarily limited to the United States where they are bred for eggs and meat. They are known to grow relatively fast and are easy to handle.
The bean goose is a goose that breeds in northern Europe and Eurosiberia. It has two distinct varieties, one inhabiting taiga habitats and one inhabiting tundra. These are recognised as separate species by the American Ornithologists' Union and the IOC, but are considered a single species by other authorities, such as the British Ornithologists' Union. It is migratory and winters further south in Europe and Asia.
The dusky Canada goose is a subspecies of the Canada goose. They are the darkest variant, similar to the Pacific cackling goose. Tagged dusky geese have red bands with white letters on them attached to their neck. They represent one of the smallest populations of Canada goose in the Pacific Northwest. Due to the species minimal population and exclusive breeding grounds, the dusky Canada goose is a species of interest to the Pacific Flyway Council and the U.S. Forest Service. The Cordova Ranger District, on the Chugach National Forest, has been working since 1984 to implement a monitoring and restoration program for the geese.