Lifespan, longevity, and ageing

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Observations: The total gestation time probably includes a period of delayed implantation (Ronald Nowak 2003). In the wild, these animals have been estimated to live up to 23 years (David Macdonald 1985). Their longevity in captivity has not been studied in detail and hence their maximum longevity must be classified as unknown.
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Behavior

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Antarctic fur seals use vocalizations to communicate. Males use two main calls. One is a threatening roar which is directed towards other males. Else, it is used as a response to a specific threat, such as a predator. The other call they make is a "huff-chuff". This call is used when moving around breeding territories, interacting with females, and is used as a sign of status. Females can roar and "huff-chuff", but their main form of communication is with their pups. They use both sound and smell to establish a bond. The sound is a high pitched call that is reinforced after the pup is born so when the mother returns from hunting trips she can make the sound and the pup will recognize it. The mother and pup use smell at close distances to confirm each other's identity.

Communication Channels: acoustic ; chemical

Perception Channels: visual ; tactile ; acoustic ; chemical

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Widener, C. 2013. "Arctocephalus gazella" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Arctocephalus_gazella.html
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Carson Widener, Radford University
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Karen Francl, Radford University
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Kiersten Newtoff, Radford University
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Laura Podzikowski, Special Projects
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Conservation Status

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The number of Antarctic fur seals were reduced to below 3,000 individuals in the 1800s. In 1964, they became a “specially protected species,” which is a term given only to the “most vulnerable and endangered species,” (Proposal to De-list, 2006). Since then, Antarctic fur seals have greatly extended their range and are at little risk of extinction. Total population numbers are estimated at four to seven million seals and are increasing. In the CITES appendices Antarctic fur seals are listed in Appendix II, indicating that while they are not currently threatened with extinction they may become so unless trade is closely controlled.

US Federal List: no special status

CITES: appendix ii

State of Michigan List: no special status

IUCN Red List of Threatened Species: least concern

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Widener, C. 2013. "Arctocephalus gazella" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Arctocephalus_gazella.html
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Carson Widener, Radford University
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Karen Francl, Radford University
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Laura Podzikowski, Special Projects
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Benefits

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There are no known adverse effects of Antarctic fur seals on humans.

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Widener, C. 2013. "Arctocephalus gazella" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Arctocephalus_gazella.html
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Carson Widener, Radford University
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Karen Francl, Radford University
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Benefits

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In the 1800 and 1900s Antarctic fur seals were widely hunted for their fur. Since this time, however, Antarctic fur seals have had little economic importance to humans. Although, increasing commercial krill harvesting could affect populations in the future.

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Widener, C. 2013. "Arctocephalus gazella" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Arctocephalus_gazella.html
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Carson Widener, Radford University
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Associations

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Members of Antarctic fur seals are key predators of krill and various species of fish and squid. It has been found that there is a correlation between size of breeding colonies and prey availability, based upon short term environmental changes and the effect it has on the reproductive success of females.

Lungworms infect three members of the fur seals group. These parasites infect the lungs of their host.

Commensal/Parasitic Species:

  • lungworms Parafilaroides species
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Widener, C. 2013. "Arctocephalus gazella" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Arctocephalus_gazella.html
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Carson Widener, Radford University
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Laura Podzikowski, Special Projects
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Trophic Strategy

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Antarctic fur seals mainly feed on fish, krill, crustacean, and cephalopods, such as squid and octopods. Fish consitute almost 75% of the diet in non-winter months. At the South Georgia Islands, the main fish prey is the mackerel icefish. However, they also consume krill in large quantities as well. Lactating females mainly feed on krill. If krill is unavailable, they turn to fish. During winter months, adult and sub-adult males feed on 50% krill and 50% fish. They also prey on some smaller penguins (4-8 kg) as well, such as rockhopper and macaroni penguins. Previous studies suggested that fur seals only attacked king penguins on land, but Charbonnier et al. (2007) observed that adult males attack king penguins at sea, too. Although adult male and female Antarctic fur seals chased king penguins at sea, only adult males were successful in catching and killing or injuring the penguins.

Animal Foods: birds; fish; aquatic crustaceans

Primary Diet: carnivore (Eats terrestrial vertebrates, Piscivore , Eats non-insect arthropods)

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Widener, C. 2013. "Arctocephalus gazella" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Arctocephalus_gazella.html
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Carson Widener, Radford University
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Karen Francl, Radford University
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Laura Podzikowski, Special Projects
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Distribution

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Arctocephalus gazella, the Antarctic fur seal, has a very wide distribution. They are mostly found in waters south of the Antarctic Convergence, but some do inhabit areas slightly north of the Convergence. Most breeding populations are found on South Georgia Island and Bird Island, while other populations are found in the south Prince Edward, Crozet, Kerguelen, and Macquarie Islands. Vagrants, however, have been observed in the southern part of South America and the Juan Fernandez Islands. Populations in the south Indian Ocean, south of the polar front, are found on Heard and McDonald Islands and north of the polar front on distances and have been seen from these breeding islands up to the ice edge of the polar front. Females leave the breeding islands during the winter and between breeding seasons travelling south to the marginal ice zone and across the polar front. Bulls often remain at the breeding islands during winter. Pups stay close to the beaches where they were born but usually move on to the ocean as winter progresses.

Biogeographic Regions: antarctica (Native )

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Widener, C. 2013. "Arctocephalus gazella" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Arctocephalus_gazella.html
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Carson Widener, Radford University
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Karen Francl, Radford University
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Kiersten Newtoff, Radford University
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Laura Podzikowski, Special Projects
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Habitat

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Antarctic fur seals spend much of their time in the ocean, hunting for food. While on land, they prefer to stay in rocky habitats but will go to beaches and zones of vegetation. Males can dive up to a maximum of 350 meters, while females can only reach up to 210 meters. Females can travel long distances in the open ocean for long periods of time between breeding.

Range depth: 350 (high) m.

Habitat Regions: polar ; terrestrial ; saltwater or marine

Aquatic Biomes: pelagic ; coastal

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Widener, C. 2013. "Arctocephalus gazella" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Arctocephalus_gazella.html
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Carson Widener, Radford University
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Karen Francl, Radford University
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Laura Podzikowski, Special Projects
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Life Expectancy

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In captivity the lifespan of Antarctic fur seals has not been well studied and it remains unknown. In the wild, males live up to 15 years, while females can live up to 25 years.

Range lifespan
Status: wild:
25 (high) years.

Average lifespan
Sex: female
Status: wild:
23.0 years.

Average lifespan
Sex: male
Status: wild:
13.0 years.

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Widener, C. 2013. "Arctocephalus gazella" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Arctocephalus_gazella.html
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Carson Widener, Radford University
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Karen Francl, Radford University
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Kiersten Newtoff, Radford University
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Laura Podzikowski, Special Projects
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Morphology

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Sexual dimorphism is very evident in Antarctic fur seals. Males are four to five times heavier than females and one and a half times longer. The average length of the males is 180 cm while the average length of females is 129 cm. The average weight of males is 133 kg and for females it is just 34 kg. Their body is covered in hair except for the areas around the rhinarium (area around the nostrils), ear tips, and the palmar surface of the flippers. They have two different layers of hair, the under-pelt, which is made up of fine fur for insulation, and the other layer, which has two different types of guard hairs. These seals have nails on their hind flippers that are well developed and used for grooming. Antarctic fur seals also have the longest facial vibrissae, or whiskers, of any other pinniped, reaching up to 45 cm in bulls. The bodies in both males and females are thick, with long necks. Males are grayish brown in color, while their face is a darker gray. The chest may appear to be a silvery gray color as well. They have a heavy, grizzled mane. Female coats are also grayish brown in color, but their chest and neck are often white to gray. Pups are born black, with a grayish brown belly. They later molt to be completely grayish brown. About one out of every 100 pups born is born with leucistic morph resulting in a creamy white or yellow white exposed skin, which is normally pigmented. They have large canines that are used in territorial fights among males. A strong correlation has been found between canina length, mass, and width in male Antarctic fur seals and body size.

Range mass: 34 to 133 kg.

Range length: 129 to 180 cm.

Sexual Dimorphism: male larger; ornamentation

Other Physical Features: endothermic ; bilateral symmetry

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Widener, C. 2013. "Arctocephalus gazella" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Arctocephalus_gazella.html
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Carson Widener, Radford University
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Karen Francl, Radford University
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Kiersten Newtoff, Radford University
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Laura Podzikowski, Special Projects
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Associations

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One major predator of Antarctic fur seeals are the leopard seals. They are a major contributor to high seal pup mortality rates especially between January and March before the pups are weaned. This has limited the growth of the colony at Elephant and Livingston Islands in the South Shetlands. Antarctic fur seals also are also preyed upon by killer whales and sharks.

Known Predators:

  • Leopard seal (Hydrurga leptonyx)
  • killer whales (Orcinus orca)
  • sharks
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Widener, C. 2013. "Arctocephalus gazella" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Arctocephalus_gazella.html
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Carson Widener, Radford University
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Karen Francl, Radford University
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Kiersten Newtoff, Radford University
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Melissa Whistleman, Radford University
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Laura Podzikowski, Special Projects
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Reproduction

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Antarctic fur seals are polygynous and breed in colonies. Adult males arrive and establish territories, about one month before breeding females come ashore, which is around mid October or early November. Females give birth to pups conceived from the previous season. They mate again around six to seven days post-birth. Maintaining territories is very costly for males. They lose about 1.5 kg in weight per day and obtain face injuries from territorial disputes. Consequently, males do not tend to hold territory until they are at least eight years old. This also encourages a dominance hierarchy on the breeding beaches. The most successful males defend the most desirable territories (those near the water but above the high water mark). The weaker males occupy territories higher up the beach. Each territorial male is associated with, on average, 15 females or between 1 to 27 females.

Mating System: polygynous

Once returning to shore females give birth to one pup, on average, conceived from the previous year. The gestation period is 11.75 months and implantation is possibly delayed. Newborn pups weigh 6 kg on average. Males and females return to breeding sites, even within a few meters of previous territories. Survival of their young from previous years probably encourages returning to the same spot year after year. Pups are born in October or early November and weigh about six kilograms on average. While the mother is away, pups roam about and interact with each other. By early January some pups are already going to the water but cannot swim well until March. Females use vocalizations to find the pup once she is back on land and confirms the pup by scent. Pups are weaned at about 117 days and become reproductively mature at three or four years old.

Breeding interval: Antarctic fur seals breed once a year.

Breeding season: Antarctic fur seals breed during the month of December.

Range number of offspring: 0 to 2.

Average gestation period: 11.75 months.

Average weaning age: 117 days.

Range age at sexual or reproductive maturity (female): 3 to 4 years.

Range age at sexual or reproductive maturity (male): 3 to 4 years.

Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); sexual ; delayed implantation

Average birth mass: 6000 g.

Average gestation period: 257 days.

Average number of offspring: 1.

Female Antarctic fur seals have to regularly forage for food during the growth of their pups. Females alternate foraging trips with short suckling bouts until the pups are weaned after about 117 days. They forage at sea for 1 to 13 days at a time with an average trip duration of 5 days. They then return to feed the pup for about two days before returning to sea.

Parental Investment: female parental care ; pre-hatching/birth (Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Provisioning: Female, Protecting: Female)

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Widener, C. 2013. "Arctocephalus gazella" (On-line), Animal Diversity Web. Accessed April 27, 2013 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Arctocephalus_gazella.html
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Carson Widener, Radford University
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Karen Francl, Radford University
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Kiersten Newtoff, Radford University
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Laura Podzikowski, Special Projects
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Species Abstract

provided by EOL authors
The Arctarctic fur seal (also Kerguelen fur seal; scientific name: Arctocephalus gazella) is one of 16 species of marine mammals in the family of Eared Seals which include sea lions and fur seals. Together with the families of True seals and Walruses, Eared seals form the group of marine mammals known as pinnipeds. Eared seals differ from the true seals in having small external earflaps and hind flippers that can be turned to face forwards. Together with strong front flippers, this gives them extra mobility on land and an adult fur seal can move extremely fast across the beach if it has to. They also use their front flippers for swimming, whereas true seals use their hind flippers. Like other Eared seals, the male Antarctic fur seal is considerably larger than the female. Adults are covered with a dense velvety underpelt, which is both waterproof and windproof, and an outer layer of coarse grey-brown hair. The males can be distinguished from the females by their long mane of shoulder fur. In the species polygynous mating system, a dominance hierarchy of males is established through displays and fights that occur while defending territories. The Antarctic fur seal is surprisingly agile on land, attaining terrestrial speeds of twenty kilometers per hour on smooth surfaces. The breeding range of Antarctic fur seal is chiefly restricted to seasonally ice free islands south of the Antarctic Convergence, but some individuals have been found as far north as Brazil. South Georgia is the site of the greatest concentration of Antarctic fur seals, particularly on Bird Island. It is estimated that 95% of the species breed near the coast of South Georgia. Other breeding locations include King George Island, Bouvet Island, Crozet Islands, Heard Island, Kerguelen Islands, Macquarie Island, Marion Island, McDonald Islands, Prince Edward Islands, South Orkney Islands, South Sandwich Islands, and South Shetland Islands. The species population may be above four million. As with other fur seals, the Antarctic fur seal was long hunted for its skin and oil and was nearly driven to extinction at one time.
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Encyclopedia of Life; Peter Saundry. 2009. Antarctic fur seal. eds. Marion McClary, C.Michael Hogan, Cutler J.Cleveland. Encyclopedia of Earth. National Council for Science and the Environment. Washington DC
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C. Michael Hogan (cmichaelhogan)
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Diagnostic Description

provided by FAO species catalogs
The muzzle is short and moderately pointed. The nose does not extend much past the mouth, is not bulbous, and the nostrils point ahead. The ear pinnae are long, prominent, and naked at the tip. The creamy white vibrissae of adults are very long, particularly in bulls; some are the longest of any pinniped (up to 35 to 50 cm). The foreflippers are about one-third, and hindflippers slightly more than one-fourth, the total length. Adult males develop a mane on the chest, neck, and top of the head. There is an enlargement of this area with muscle and fat that occurs with maturity.

Adult females and subadults are medium grey, occasionally darker above, and paler below. There is usually a pale blaze on the flanks, extending towards the hindflippers. The chest and underside of the neck are palest; this pale colour extends onto the sides and back of the neck. The muzzle and face are also marked with lighter areas. Additional lighter areas often surround and highlight the ears, particularly in adult females and subadults. The tops of the flippers are generally darker than the back. At birth, pups are blackish, though they may be pale on the face and muzzle, and some animals are paler below. Adult males are dark greyish brown to charcoal, with frosting on the guard hairs of the back, mane, and flanks (these guard hairs often bunch up and reveal the fawn coloured underfur). There is an unusual pale (yellowish off-white to honey) form of the Antarctic fur seal that occurs infrequently.

The dental formula is I 3/2, C 1/1, PC 6/5.

Can be confused with: Antarctic fur seals might be confused with many southern otariids, most notably: Subantarctic fur seal, South American fur seal, Juan Fernandez fur seal, South African fur seal, and New Zealand fur seal, and South American sea lion and Hooker's sea lion. To distinguish bulls of the different fur seals, note overall size, characteristics of the muzzle and nose, coloration, relative length of the flippers, and length of the vibrissae (keeping in mind that vibrissae may be broken off).In some cases, it may not be possible to separate adult female and subadult fur seals. Most useful are body shape, coloration, vibrissae, ear size, eye shape, and flipper size and shape.

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Marine mammals of the world. Jefferson, T.A., S. Leatherwood & M.A. Webber - 1993. FAO species identification guide. Rome, FAO. 320 p. 587 figs. . 
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Food and Agriculture Organization of the UN
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Size

provided by FAO species catalogs
Adult males are up to 2 m long and weigh 110 to 230 kg, females up to 1.4 m and 22 to 51 kg. Newborns are about 63 to 67 cm and 6 to 7 kg.
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Marine mammals of the world. Jefferson, T.A., S. Leatherwood & M.A. Webber - 1993. FAO species identification guide. Rome, FAO. 320 p. 587 figs. . 
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Food and Agriculture Organization of the UN
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Brief Summary

provided by FAO species catalogs
Breeding is from late November to late December. After they mate and wean their pups, females disperse widely, possibly migrating north. Bulls also depart breeding areas, but subadults and adults can be seen around the rookeries at South Georgia all year.

Like other fur seals, Antarctic fur seals porpoise when swimming rapidly. When rafting they often assume the typical fur seal resting posture. At other times, they can be found busily engaged in grooming. Antarctic fur seals, especially adult females, feed heavily on krill, but also take fish in summer. Dietary patterns of females in summer indicate nocturnal feeding.

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Marine mammals of the world. Jefferson, T.A., S. Leatherwood & M.A. Webber - 1993. FAO species identification guide. Rome, FAO. 320 p. 587 figs. . 
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Food and Agriculture Organization of the UN
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Benefits

provided by FAO species catalogs
Conservation Status : This species was nearly exterminated by sealers. Harvesting occurred with numerous highs and lows in activity from the late 18th until the early 20th Century. Estimates are that only a few hundred may have survived. Rapid population growth occurred from 1958 to 1972 and slower but continuous growth from that point until the present. Although the population of Antarctic fur seals is still growing, entanglement of these seals in debris at a rate of 0.1 to 1% at South Georgia may become a factor in the stability of this species. IUCN:

Insufficiently known.

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Marine mammals of the world. Jefferson, T.A., S. Leatherwood & M.A. Webber - 1993. FAO species identification guide. Rome, FAO. 320 p. 587 figs. . 
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Food and Agriculture Organization of the UN
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Antarctic fur seal

provided by wikipedia EN

The Antarctic fur seal (Arctophoca gazella), is one of seven seals in the genus Arctophoca, and one of nine fur seals in the subfamily Arctocephalinae. Despite what its name suggests, the Antarctic fur seal is mostly distributed in Subantarctic islands[2] and its scientific name is thought to have come from the German vessel SMS Gazelle, which was the first to collect specimens of this species from Kerguelen Islands.[3]

Description

 src=
Antarctic fur seal pups on Salisbury Plain, South Georgia

This fur seal is a midsized pinniped with a relatively long neck and pointed muzzle compared with others in the family. The nose does not extend much past the mouth, the external ears are long, prominent, and naked at the tip. Adults have very long vibrissae, particularly males, up to 35 to 50 cm. The fore flippers are about one-third, and hind flippers slightly more than one-fourth, of the total length.[4] These seals find the antarctic warm so they take plunges in cold water to stay cold.

Adult males are dark brown in colour. Females and juveniles tend to be paler, almost grey with lighter undersides. Colour patterns are highly variable, and scientists reported that some hybridization between Subantarctic and Antarctic fur seals has occurred.[5][6] Pups are dark brown at birth, almost black in color. About one in 1000 Antarctic fur seals are pale 'blonde' variants - not albino - and they stay so as adults.[7]

Males are substantially larger than females. Males grow up to 2 m (6.5 ft) long and with a mean weigh of 133 kg (293 lb). Females reach 1.4 m (4.6 ft) with a mean weight of 34 kg (74.9 lb). At birth, mean standard length is 67.4cm (58–66) and mass is 5.9kg (4.9–6.6) in males and 5.4kg (4.8–5.9) in females.[8]

Antarctic fur seals live up to 20 years with a maximum observed for female of 24.[9]

Geographic Range and Distribution

Antarctic fur seals are believed to be the most abundant species of fur seal.[10] The largest congregation occurs on South Georgia, which holds approximately 95% of the global population.[11] The current best estimate for South Georgia is 4.5-6.2 million animals and 46,834 at Bouvetøya.[12] However, there are regional differences in population trends: some colonies are increasing in size (e.g. Kerguelen Islands, McDonald Islands), some are stables (e.g. Macquarie Island, Heard islands), some showing decrease (e.g. Bouvetøya).[13]

Antarctic fur seals have a circumpolar distribution and breed from 61° S to the Antarctic Convergence. Breeding colonies are found at South Georgia and the South Sandwich Islands, South Orkney Islands, South Shetland Islands and Bouvetøya in the Southern Atlantic Ocean; Marion Island, Crozet Islands, Kerguelen and Heard Island in the Southern Indian Ocean; and Macquarie Island in the Southern Pacific Ocean.[14] During winter, Antarctic fur seals range widely from the Antarctic continent to the Falkland Islands, and southern Argentina and Chile, reaching as far as the Mar del Plata and Gough Island.[15][16]

Behavior

 src=
Antarctic fur seal swimming near Clarence Island

Antarctic fur seals are one of the better-studied Southern Ocean predators. However, the vast majority of information has been collected during summer breeding months. The breeding system of the Antarctic Fur Seal is polygynous, and dominant breeding males mate with as many as 20 females during a successful season. Males establish breeding grounds in October to early November.[17] Females generally reach the colonies in December and give birth to a single pup several days later.[18] Gestation lasts between 8 and 9 months and it has been observed a high breeding synchrony across the species’ range, concentrating 90% of pup births in a 10-day window. Pups are weaned at about four months old.[19] Juveniles may then spend several years at sea before returning to begin their breeding cycles.

The ecology of Antarctic fur seals during the non-breeding winter is poorly understood. Adult and subadult males may form groups while moulting along the Antarctic Peninsula in late summer and early autumn. Adult females are gregarious but relatively asocial other than the strong bond they establish with their pups, although there are occasional aggressive encounters with nearby females or other pups and brief interactions with adult males to mate. These seals appear to be solitary when foraging and migrating.[20]

The usual food source for individuals in the Atlantic Region is Antarctic krill (Euphausia superba); while in the Indian Ocean the diet is mostly based on fish and squid. The fish prey are principally myctophids, icefish, and Notothenids, although skates and rays are also consumed.[21] Penguins are occasionally taken by Antarctic fur seal males.[22] Seasonal differences in diet have been recorded across colonies, seasons and years.[23][24] Studies have showed that female Antarctic fur seals can undertake wide-ranging foraging migrations during winter.[25] Interannual differences appear to be related to differences in local oceanographic conditions.[26][27]

Taxonomy

Antarctic fur seals are member of the genus Arctophoca, but were formerly classified in the genus Arctocephalus.

Antarctic fur seals can be confused with southern otariids that share their range, like Subantarctic (A. tropicalis), New Zealand (A. forsteri), and South American fur seals (A. australis), and the Juan Fernandez fur seal (A. phillippii), as well as the South American (Otaria flavescens) and New Zealand sea lions (Phocarctos hookeri), are the most likely species to consider.[28] Genetic studies on population structure[29] have suggests that there are two genetically distinct regions: a western region including the islands of the Scotia Arc, Bouvetøya, and Marion Islands, and an eastern region, including Kerguelen and Macquarie Islands. Seals from Crozet Islands and Heard Island are mixtures from both regions.

Population status

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Antarctic fur seals and king penguins at Salisbury Plain, South Georgia

South Georgia islands, which hold approximately 95% of the global population,[30] had a total population in 1999/2000 between 4.5 and 6.2 million.[31] The South Georgia population reached carrying capacity fairly recently and may thus be spilling over into relatively nearby, lower density sites.[32] However, the abundance of adult females is estimated to have declined by some 30% between 2003 and 2012, and by 24% since 1984 to around 550,000. The population trend according to the IUCN Red list is ‘decreasing’ and it has been suggested that this decline is due to the effects of global climate change on prey availability.[33]

Threats

Historically the species were decimated by the sealing industry for its fur and its population was driven close to extinction by the 19th century.[34] Since sealing operations ceased in the early 20th century, the species has recovered at different rates across its former geographic range.[35]

Waters inhabited by Antarctic Fur Seals are exploited by few fisheries, but these may expand in their range in the future.[36] A 1997 study at South Georgia indicated that several thousand Antarctic fur seals were entangled in man-made debris such as discarded fishing line, nets, packing bands and anything that can form a collar.[37] Consequently, CCAMLR campaigned for compliance with MARPOL provisions relating to waste disposal at sea, and for cutting of any material jettisoned which could form collars to entangle seals. Subsequent monitoring of entangled fur seals confirmed that entanglement is still a persistent problem, but it has halved in recent years.[38] Trawling activities developing around Macquarie Island may affect the prey base of the primarily fish-eating Antarctic fur seals that breed on those islands. Recent work indicates that there is significant overlap between foraging areas and fisheries activities, suggesting a potential for competition for prey resources may exist.

Leopard Seals have been noted to take as many as a third of the Antarctic Fur Seal pups born at sites in the South Shetland Islands.[39] Levels of predation may be high enough to cause a population decline at these sites.[40] New Zealand Sea Lions have been reported to kill up to half of the Antarctic Fur Seal pup production in a season at Macquarie Island.[41]

As well as the effects of hunting and fishing, the numbers of humans visiting the Antarctic and sub-Antarctic each year for tourism and scientific expeditions has risen. This increase in visits has led to greater interaction between the local fauna and humans.[42] With this greater interaction comes the risk of impacting the territoriality of seals especially during the mating season. This can also increase the possibility of ‘exotic’ injuries to humans. In 2015 a man was rescued from a South Georgia Island by British Forces after receiving a serious bite from a fur seal.[43] Due to the remote location of where these injuries occur this can lead to complications in getting people to a physician with the relevant experience in treating exotic animal bites. This issue is compounded by the complexity of fur seal behavior and how serious a bite can be[44] and the risk of transfer of diseases.[45] The implication for Antarctic Fur Seals but this species is considered to be one of several pinnipeds at high risk of future disease outbreaks because of their tendency to congregate in large dense aggregations and the effect of environmental changes associated with global warming on the spread of diseases.[46]

Finally, the 19th century population bottleneck led to reduced genetic diversity, leaving it again more vulnerable to disease and stresses of climate change. In particular, the Antarctic fur seal's primary prey base, krill, could be reduced as a result of ocean acidification, or the distribution could be altered by climate change.

Conservation status

IUCN Conservation status: Least Concern.[47] The species is protected by the governments in whose waters it resides (Australia, South Africa, France) and by the Convention for the Conservation of Antarctic Seals in waters south of 60° S.[48] The animal is also listed in Appendix 2 of CITES.[49]

References

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Antarctic fur seal: Brief Summary

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The Antarctic fur seal (Arctophoca gazella), is one of seven seals in the genus Arctophoca, and one of nine fur seals in the subfamily Arctocephalinae. Despite what its name suggests, the Antarctic fur seal is mostly distributed in Subantarctic islands and its scientific name is thought to have come from the German vessel SMS Gazelle, which was the first to collect specimens of this species from Kerguelen Islands.

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