Guadalupe Fur Seal (Arctocephalus townsendi)

Guadalupe Fur Seal
(Arctocephalus townsendi)
Photo: NOAA

Did You Know?

· Guadalupe fur seals' breeding grounds are almost entirely on Guadalupe Island, Mexico.

· In the early 1900s, the Guadalupe fur seal was thought to be extinct.

· Guadalupe fur seals rest in the water with their head and their hindflippers jutting out of the water.

Status
ESA Threatened - throughout its range
MMPA Depleted - throughout its range

Taxonomy
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Otariidae
Genus: Arctocephalus
Species: townsendi

Species Description
Guadalupe fur seals are members of the "eared seal" family, Otariidae. Guadalupe fur seals are sexually "dimorphic" with males reaching average lengths of about 7 ft (2 m) and weighing about 400 lbs (180 kg) while females average lengths and weights are much smaller at about 5 ft (1.5 m) and 110 lbs (50 kg), respectively. They have a narrow, flat head with a pointed, narrow, and long snout. Their foreflippers are broad, with some hair, reaching slightly past their wrist. Their coloration is dark brown to black with adult males having tan or yellow hairs on the back of the mane.

Guadalupe fur seals are solitary, non-social animals. Males are "polygamous" and may mate with 4 to 12 females during a single breeding season. Males form small territories that they defend by roaring or coughing. Breeding season is June through August, with females arriving in early June; pups are born a few days after their arrival. A female will mate about a week after giving birth to her pup. Weaning occurs around 9 months.

Guadalupe fur seals feed mainly at night on squid, mackerel, and lantern fish by diving up to depths of 65 ft (20 m).

Habitat
Guadalupe fur seals reside in the tropical waters of the Southern California/Mexico region. During breeding season, they are found in coastal rocky habitats and caves. Little is known about their whereabouts during the non-breeding season (May to September).

Distribution
Guadalupe fur seals are non-migratory and their breeding grounds are almost entirely on Guadalupe Island, Mexico. There are small populations off of Baja California on San Benito Island and off of Southern California at San Miguel Island. It is the only species of the Arctocephalus genus that occurs north of the equator.

Population Trends
The Guadalupe fur seal population is slowly recovering from the brink of extinction. The current population abundance is approximately 10,000 animals. Of all the fur seal species, this one is the least studied due to their limited geographic locations. The Guadalupe fur seal population is increasing about 13.7% annually.

Threats
In the 1700s and 1800s, commercial sealers heavily hunted Guadalupe fur seals to the point where the species was thought to be extinct by the early 1900s. Insufficient data exist on the incidental bycatch of Guadalupe fur seals in fishing gear, although some juvenile seals have been documented with entanglement injuries.

Conservation Efforts
Guadalupe fur seals are classified as Vulnerable on the IUCN Red List .

Regulatory Overview
The Guadalupe fur seal was listed as threatened throughout its range on December 16, 1985 under the Endangered Species Act of 1973 and is also protected under the Marine Mammal Protection Act of 1972, as amended. In 1975, the government of Mexico declared Guadalupe Island a pinniped sanctuary. NMFS has classified the U.S. Guadalupe fur seal stock as a "strategic" stock.

Key Documents
(All documents are in PDF format.)

Title	Federal Register	Date
ESA Listing Rule	50 FR 51252	12/16/1985
Stock Assessment Reports	n/a	various

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