Guadalupe fur seal

Last updated

Guadalupe fur seal
Arctocephalus townsendi.jpg
CITES Appendix I (CITES) [2]
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Clade: Pinnipedia
Family: Otariidae
Genus: Arctocephalus
Species:
A. townsendi
Binomial name
Arctocephalus townsendi
Merriam, 1897
Arctocephalus townsendi distribution.png
Dark blue: breeding colonies; light blue: other colonies

The Guadalupe fur seal (Arctocephalus townsendi) is one of eight members of the fur seal genus Arctocephalus . They are the northernmost member of this genus. Sealers reduced the population to just a few dozen by the late 19th century, but the species had recovered to 10,000 in number by the late 1990s. Many individuals can be found on Mexico's Guadalupe Island.

Contents

Description

Adult Guadalupe fur seals are dark brown or dusty gray with yellowish silver manes, called guard hairs, on the back of the neck. [3] Guadalupe fur seals are sexually dimorphic in size, as males are much larger and heavier than females; males can grow to about seven feet in length and weigh upwards of 400 pounds, while females are typically only five feet long and weigh about 110 pounds. [4] Additionally, males usually have a larger head and are lighter brown in color. Both males and females have a twenty-year lifespan. Guadalupe fur seals have distinctive ear flaps and large flippers for walking on land, confirming that they are not phocids (true seals) but are more closely related to sea lions. [5] Guadalupe fur seal pups are born with black coats similar to those of adult Guadalupe fur seals, but it is difficult to distinguish juvenile Guadalupe fur seals from juveniles of California sea lions and Northern fur seals due to physiological similarities.

Distribution and habitat

Guadalupe fur seals breed along the eastern coast of Guadalupe Island, approximately 200 km west of Baja California. In addition, individuals have been sighted in the southern California Channel Islands, including two males who established territories on San Nicolas Island. Stray seals have been found as far north as Oregon. [6]

Guadalupe fur seals were known to reside in Baja California, Mexico and Southern California but were heavily hunted in the 19th century and were believed to be extinct. However, the animals were found on Isla Guadalupe, Baja California in a cave in 1954; this is now the only place of Guadalupe fur seal reproduction. In 2013, the population of Guadalupe fur seals was estimated to be between 34,000 and 44,000, around one-fifth of the estimated historical population size. [7]

Feeding

Guadalupe fur seals are a pelagic species that spend most of their time on the open ocean. [8] Thus, they dive to catch food and forage for about two weeks before returning to land to feed. Guadalupe fur seals commonly hunt in shallow water (maximum depth of 250 feet/76 meters) and catch squid, mackerels, and lanternfish. They feed exclusively at night.

Behavior

Guadalupe fur seals create caves on land which can causes social pressures amongst the individuals. The seals that do not breed often play with each other by barking, lunging at each other, and pushing each other into the water. Other behaviors of the animal consist of waving their hind flippers in the water whist face down in the water. Additionally, when interacting with humans, these seals are not typically aggressive. They are often seen with their heads under the water and pay little attention to the observer. [9]

Breeding

Observations suggest that males of reproducing age claim particular sites for a number of years, though territorial fights are uncommon amongst males once regions have been taken. Tenure of territorial males lasts from 35 to 122 days. Males mate with up to twelve females during mating season, and births occur from mid-June through mid-July, though most births take place in June. After birth, females nurse their pups for 8–10 days. In the nine months following the birth, females alternate between spending 9–13 days foraging food for and spending 5–6 days nursing pups. [10] After this period, the pups are considered adults and are on their own. Mothers and pups recognize each other by unique noises and smells.

Impacts on Guadalupe fur seals

The major cause of the Guadalupe fur seal's decline was commercial hunting in the late 18th and early 19th centuries. The species was exterminated in southern California waters by 1825. Commercial sealing continued in Mexican waters through 1894.

Conservation and recovery efforts

The species is listed as Threatened by the U.S. National Marine Fisheries Service under the Endangered Species Act. [11] The principal cause of the decline in Guadalupe fur seals was commercial sealing. The species is now protected from such activity throughout its range, and the magnitude of the threat to the species is considered to be low. The portion of the Guadalupe fur seal's range which is under U.S. jurisdiction is at the limit of the species range. No activities in areas under U.S. jurisdiction are known to be adversely affecting recovery of this species now. Therefore, management activities in the U.S. portion of its range are not likely to contribute substantially to recovery. However, Guadalupe fur seals are protected from federal actions that are likely to jeopardize the species through interagency coordination under Section 7 of the Endangered Species Act. No other specific actions necessary for the recovery of the species have been identified, and no direct recovery actions are being implemented.

In Mexico, the Guadalupe fur seal, where the seal was discovered after being believed to be extinct, is protected in the Guadalupe Island Biosphere Reserve.

Related Research Articles

<span class="mw-page-title-main">Fur seal</span> Subfamily of mammals

Fur seals are any of nine species of pinnipeds belonging to the subfamily Arctocephalinae in the family Otariidae. They are much more closely related to sea lions than true seals, and share with them external ears (pinnae), relatively long and muscular foreflippers, and the ability to walk on all fours. They are marked by their dense underfur, which made them a long-time object of commercial hunting. Eight species belong to the genus Arctocephalus and are found primarily in the Southern Hemisphere, while a ninth species also sometimes called fur seal, the Northern fur seal, belongs to a different genus and inhabits the North Pacific. The fur seals in Arctocephalus are more closely related to sea lions than they are to the Northern fur seal, but all three groups are more closely related to each other than they are to true seals.

<span class="mw-page-title-main">Eared seal</span> Marine mammals in the family Otariidae

An eared seal, otariid, or otary is any member of the marine mammal family Otariidae, one of three groupings of pinnipeds. They comprise 15 extant species in seven genera and are commonly known either as sea lions or fur seals, distinct from true seals (phocids) and the walrus (odobenids). Otariids are adapted to a semiaquatic lifestyle, feeding and migrating in the water, but breeding and resting on land or ice. They reside in subpolar, temperate, and equatorial waters throughout the Pacific and Southern Oceans, the southern Indian, and Atlantic Oceans. They are conspicuously absent in the north Atlantic.

<span class="mw-page-title-main">Sea lion</span> Subfamily of aquatic mammals

Sea lions are pinnipeds characterized by external ear flaps, long foreflippers, the ability to walk on all fours, short and thick hair, and a big chest and belly. Together with the fur seals, they make up the family Otariidae, eared seals. The sea lions have six extant and one extinct species in five genera. Their range extends from the subarctic to tropical waters of the global ocean in both the Northern and Southern Hemispheres, with the notable exception of the northern Atlantic Ocean. They have an average lifespan of 20–30 years. A male California sea lion weighs on average about 300 kg (660 lb) and is about 2.4 m (8 ft) long, while the female sea lion weighs 100 kg (220 lb) and is 1.8 m (6 ft) long. The largest sea lions are Steller's sea lions, which can weigh 1,000 kg (2,200 lb) and grow to a length of 3.0 m (10 ft). Sea lions consume large quantities of food at a time and are known to eat about 5–8% of their body weight at a single feeding. Sea lions can move around 16 knots in water and at their fastest they can reach a speed of about 30 knots. Three species, the Australian sea lion, the Galápagos sea lion and the New Zealand sea lion, are listed as endangered.

<span class="mw-page-title-main">Pinniped</span> Infraorder of mammals

Pinnipeds, commonly known as seals, are a widely distributed and diverse clade of carnivorous, fin-footed, semi-aquatic, and mostly marine mammals. They comprise the extant families Odobenidae, Otariidae, and Phocidae, with 34 extant species and more than 50 extinct species described from fossils. While seals were historically thought to have descended from two ancestral lines, molecular evidence supports them as a monophyletic lineage. Pinnipeds belong to the clade Caniformia of the order Carnivora; their closest living relatives are musteloids, having diverged about 50 million years ago.

<span class="mw-page-title-main">Steller sea lion</span> Species of carnivore

The Steller sea lion is a large, near-threatened species of sea lion, predominantly found in the coastal marine habitats of the northeast Pacific Ocean and the Pacific Northwest regions of North America, from north-central California to Oregon, Washington and British Columbia to Alaska. Its range continues across the Northern Pacific and the Aleutian Islands, all the way to Kamchatka, Magadan Oblast, and the Sea of Okhotsk, south to Honshu’s northern coastline. It is the sole member of the genus Eumetopias, and the largest of the so-called eared seals (Otariidae). Among pinnipeds, only the walrus and the two species of elephant seal are bigger. The species is named for the naturalist and explorer Georg Wilhelm Steller, who first described them in 1741. Steller’s sea lions have attracted considerable attention in recent decades, both from scientists and the general public, due to significant declines in their numbers over an extensive portion of their northern range—notably in Alaska.

<span class="mw-page-title-main">Northern elephant seal</span> Species of marine mammal

The northern elephant seal is one of two species of elephant seal. It is a member of the family Phocidae. Elephant seals derive their name from their great size and from the male's large proboscis, which is used in making extraordinarily loud roaring noises, especially during the mating competition. Sexual dimorphism in size is great. Correspondingly, the mating system is highly polygynous; a successful male is able to impregnate up to 50 females in one season.

<span class="mw-page-title-main">Elephant seal</span> Genus of aquatic carnivores

Elephant seals are very large, oceangoing earless seals in the genus Mirounga. Both species, the northern elephant seal and the southern elephant seal, were hunted to the brink of extinction for oil by the end of the 19th century, but their numbers have since recovered. They are the largest extant carnivorans, weighing up to 5,000 kilograms (11,000 lb). Despite their name, elephant seals are not related to elephants, and the large proboscis or trunk that males have was convergently evolved.

<span class="mw-page-title-main">Harp seal</span> Species of mammal

The harp seal, also known as Saddleback Seal or Greenland Seal, is a species of earless seal, or true seal, native to the northernmost Atlantic Ocean and Arctic Ocean. Originally in the genus Phoca with a number of other species, it was reclassified into the monotypic genus Pagophilus in 1844. In Greek, its scientific name translates to "ice-lover from Greenland," and its taxonomic synonym, Phoca groenlandica translates to "Greenlandic seal." This is the only species in the genus Pagophilus.

<span class="mw-page-title-main">Hawaiian monk seal</span> Species of carnivore

The Hawaiian monk seal is an endangered species of earless seal in the family Phocidae that is endemic to the Hawaiian Islands.

<span class="mw-page-title-main">Northern fur seal</span> Only fur seal in the northern hemisphere

The northern fur seal is an eared seal found along the north Pacific Ocean, the Bering Sea, and the Sea of Okhotsk. It is the largest member of the fur seal subfamily (Arctocephalinae) and the only living species in the genus Callorhinus. A single fossil species, Callorhinus gilmorei, is known from the Pliocene of Japan and western North America.

<span class="mw-page-title-main">Antarctic fur seal</span> Species of carnivore

The Antarctic fur seal, is one of eight seals in the genus Arctocephalus, 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.

<span class="mw-page-title-main">Subantarctic fur seal</span> Species of carnivore

The subantarctic fur seal is a species of arctocephaline found in the southern parts of the Indian, Pacific, and Atlantic Oceans. It was first described by Gray in 1872 from a specimen recovered in northern Australia—hence the inappropriate specific name tropicalis.

<span class="mw-page-title-main">Juan Fernández fur seal</span> Species of carnivore

The Juan Fernández fur seal is the second smallest of the fur seals, second only to the Galápagos fur seal. They are found only on the Pacific Coast of South America, more specifically on the Juan Fernández Islands and the Desventuradas Islands. There is still much that is unknown about this species. Scientists still do not know the average life span of this species, or the diet and behavior of males apart from the breeding season.

<span class="mw-page-title-main">Galápagos fur seal</span> Species of carnivore

The Galápagos fur seal is one of eight seals in the genus Arctocephalus and one of nine seals in the subfamily Arctocephalinae. It is the smallest of all of the eared seals. They are endemic to the Galápagos Islands in the eastern Pacific. The total estimated population as of 1970 was said to be about 30,000, although the population has been said to be on the decline since the 1980s due to environmental factors such as pollution, disease, invasive species, and their limited territory. Due to the population having been historically vulnerable to hunting, the Galápagos fur seal has been protected by the Ecuadorian government since 1934

<span class="mw-page-title-main">Brown fur seal</span> Species of carnivore

The brown fur seal, also known as the Cape fur seal, South African fur seal and Australian fur seal, is a species of fur seal.

<i>Arctocephalus forsteri</i> Species of carnivore

Arctocephalus forsteri is a species of fur seal found mainly around southern Australia and New Zealand. The name New Zealand fur seal is used by English speakers in New Zealand; kekeno is used in the Māori language. As of 2014, the common name long-nosed fur seal has been proposed for the population of seals inhabiting Australia.

<span class="mw-page-title-main">South American fur seal</span> Species of mammal

The South American fur seal breeds on the coasts of Peru, Chile, the Falkland Islands, Argentina, Uruguay and Brazil. The total population is around 250,000. However, population counts are sparse and outdated. Although Uruguay has long been considered to be the largest population of South American fur seals, recent census data indicates that the largest breeding population of A. a. australis are at the Falkland Islands followed by Uruguay. The population of South American fur seals in 1999 was estimated at 390,000, a drop from a 1987 estimate of 500,000 - however a paucity of population data, combined with inconsistent census methods, makes it difficult to interpret global population trends.

<span class="mw-page-title-main">Ribbon seal</span> Species of mammal

The ribbon seal is a medium-sized pinniped from the true seal family (Phocidae). A seasonally ice-bound species, it is found in the Arctic and Subarctic regions of the North Pacific Ocean, notably in the Bering Sea and Sea of Okhotsk. It is distinguished by its striking coloration, with two wide white strips and two white circles against dark brown or black fur.

<span class="mw-page-title-main">The Marine Mammal Center</span> Zoo in California, United States

The Marine Mammal Center (TMMC) is a private, non-profit U.S. organization that was established in 1975 for the purpose of rescuing, rehabilitating and releasing marine mammals who are injured, ill or abandoned. It was founded in Sausalito, California, by Lloyd Smalley, Pat Arrigoni and Paul Maxwell. Since 1975, TMMC has rescued over 24,000 marine mammals. It also serves as a center for environmental research and education regarding marine mammals, namely cetaceans, pinnipeds, otters and sirenians. Marine mammal abandonment refers to maternal separation; pups that have been separated from their mother before weaning. At the center, they receive specialized veterinary care: they are diagnosed, treated, rehabilitated and ideally, released back into the wild. Animals in need of assistance are usually identified by a member of the public who has contacted the center. These animals represent the following major species: California sea lions, northern elephant seals, Pacific harbor seals, northern fur seals, Guadalupe fur seals, Hawaiian monk seals, and southern sea otters. On a few occasions, TMMC has taken in Steller sea lions and bottlenose/Pacific white-sided dolphins. The only non-mammals that TMMC takes in are sea turtles.

<span class="mw-page-title-main">Guadalupe Island Biosphere Reserve</span> Natural reserve in Mexico

The Guadalupe Island Biosphere Reserve,, is located in the Pacific Ocean and is part of Baja California state of Mexico. The Reserve consists of Guadalupe Island and several small islands nearby plus a large expanse of surrounding ocean. The Reserve was created by the government of Mexico on 25 April 2005 and is located 250 kilometres (160 mi) from the mainland. The Reserve is 4,770 square kilometres (1,840 sq mi) in size of which 263 square kilometres (102 sq mi) is land and the remainder is water.

References

  1. Aurioles-Gamboa, D. (2015). "Arctocephalus townsendi". IUCN Red List of Threatened Species . 2015: e.T2061A45224420. doi: 10.2305/IUCN.UK.2015-2.RLTS.T2061A45224420.en . Retrieved 13 November 2021.
  2. "Appendices | CITES". cites.org. Retrieved 2022-01-14.
  3. Gallo-Reynoso, Juan-Pablo; Figueroa-Carranza, Ana-Luisa (2010-04-30). "Pup growth of the guadalupe fur seal, Arctocephalus townsendi". Therya. 1 (1): 75–90. doi:10.12933/therya-10-8. ISSN   2007-3364.
  4. Fisheries, NOAA (2022-09-15). "Guadalupe Fur Seal | NOAA Fisheries". NOAA. Retrieved 2022-10-21.
  5. Ventura, Mailing Address: 1901 Spinnaker Drive; Us, CA 93001 Phone: 805 658-5730 Contact. "Guadalupe Fur Seal - Channel Islands National Park (U.S. National Park Service)". www.nps.gov. Retrieved 2022-10-21.
  6. KATU Staff (2020-12-19). "Seaside Aquarium rescues abandoned seal pup on Oregon beach". KATU. Retrieved 2020-12-21.
  7. García-Aguilar, María C.; Elorriaga-Verplancken, Fernando R.; Rosales-Nanduca, Hiram; Schramm, Yolanda (2018). "Population status of the Guadalupe fur seal (Arctocephalus townsendi)". Journal of Mammalogy. 99 (6): 1522–1528. ISSN   0022-2372. JSTOR   27007996.
  8. OctoberCMS. "Guadalupe Fur Seal | The Marine Mammal Center". www.marinemammalcenter.org. Retrieved 2022-10-21.
  9. Peterson, Richard S.; Hubbs, Carl L.; Gentry, Roger L.; DeLong, Robert L. (1968). "The Guadalupe Fur Seal: Habitat, Behavior, Population Size, and Field Identification". Journal of Mammalogy. 49 (4): 665–675. doi:10.2307/1378727. ISSN   0022-2372. JSTOR   1378727.
  10. "Guadalupe Fur Seal". Oceana. Retrieved 2022-10-21.
  11. "List of Endangered Species". awionline. Animal Welfare Institute. 2020. Retrieved 22 September 2020.