Seal, Guadalupe Fur

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Seal, Guadalupe fur

Arctocephalus townsendi

phylum: Chordata

class: Mammalia

order: Carnivora

family: Otariidae

status: Vulnerable, IUCN Threatened, ESA

range: Mexico, USA (California)

Description and biology

Fur seals and sea lions differ from true seals in that they have external ear flaps. They are also able to turn their hind flippers forward for walking on land. While they use all four flippers for walking, they use only their long front flippers for swimming.

The Guadalupe fur seal can be distinguished from other fur seals by its long, pointed snout and light-colored whiskers. An average male Guadalupe fur seal may grow up to 6.5 feet (2 meters) in length and weigh up to 310 pounds (141 kilograms). Females are smaller, reaching 4.4 feet (1.3 meters) in length and weighing 110 pounds (50 kilograms).

Guadalupe fur seals have a behavioral trait that makes them unique among seals. When on land, they often retreat onto rocky recesses or into caves. Some scientists believe this

trait developed in the species in the nineteenth century when hunters mercilessly slaughtered the animals. To survive, Guadalupe fur seals withdrew to caves, a behavior that has since been passed down to the current generation.

The Guadalupe fur seal's diet includes squid and fish such as the lantern fish. The animal travels widely at sea and has been found 186 miles (300 kilometers) away from its main home range. Unlike other seals, the Guadalupe fur seal may be found on shore at any time during the year.

Mating between male and female Guadalupe fur seals takes place between May and July. Males compete with each other over the right to mate with females. A dominant male may breed with as many as ten females. After a gestation (pregnancy) period of about 12 months, a female Guadalupe fur seal gives birth in a cave to one or two pups.

Habitat and current distribution

Guadalupe fur seals range in the Pacific Ocean from the Farallon Islands off the coast of San Francisco, California, south to Islas Revillagigedo, a group of islands 450 miles (724 kilometers) off the coast of the Mexican state of Colima. The animals are known to breed only on the rocky east coast of Guadalupe Island, located west of the Baja California peninsula. Biologists (people who study living organisms) estimate the total Guadalupe fur seal population to be 6,000.

History and conservation measures

As many as 200,000 Guadalupe fur seals may have existed on Guadalupe Island alone before the nineteenth century. Hunters seeking the animals' fur and blubber (fat that was melted down to make oil) nearly wiped out the species. In fact, the Guadalupe fur seal was considered extinct until 1928, when two males were caught by fishermen. In 1954, a small breeding colony of 14 seals was discovered on Guadalupe Island. Since then, the population of Guadalupe fur seals has slowly increased.

In 1922, the Mexican government declared Guadalupe Island a wildlife sanctuary. In 1978, it declared all islands around Baja California wildlife reserves.

Despite these protective measures, the Guadalupe fur seal remains vulnerable because it has little fear of humans. Although legally protected, the animal may still fall prey to hunters. Noise from cruise ships and other human activities often prevent the Guadalupe fur seal from breeding.