Endangered Spotlight: Guadalupe Fur Seal (Arctocephalus townsendi)

Guadalupe fur seal. Photo: Bradford Hollingworth,
courtesy of Ocean Oasis.

Today, Guadalupe fur seals are rare visitors to our Sanctuary, but in the early 18th century they foraged up and down the California coast. Commercial hunting brought the species to near extinction—by 1825 they were nonexistent in California waters. By 1928, Guadalupe fur seals were considered completely extinct.

A quarter century later, a few dozen seals were rediscovered on Guadalupe Island, 200 km west of Baja California, Mexico. By the 1990’s, the species had recovered to around 10,000 seals.

Physical Appearance

In the ocean, Guadalupe fur seals are difficult to distinguish from northern fur seals, but they are slightly smaller and lighter brown in color.  They have a dark brown black coat with light hairs on the back of the neck. The seals have external ear flaps, and they have long front and hind flippers, which they use to "walk" when on land.

Guadalupe fur seals are a dimorphic species, where males are much larger than females.  Male seals reach roughly six feet and weigh 300 pounds, while females grow to four feet and weigh approximately 100 pounds.

Range and Habitat

There is evidence that Guadalupe fur seals once bred as far north as Point Conception in Central California. Today, however, the only known breeding colonies are on Isla de Guadalupe and Isla Benito del Este off the coast of Baja California.

Increasing numbers have been seen in California's Channel Islands, and in recent years, several Guadalupe fur seals have stranded along the central California coast. Individuals are occasionally sighted as far south as the Mexico-Guatemala border and as far north as the Point Reyes National Seashore in California.

The Guadalupe fur seal is the rarest of all fur seal species, and is the only species of Arctocephalus found north of the equator.  They feed on squid and fish.  Sharks are known to prey on the seals.

Mating

Guadalupe fur seals breed on rocky beaches or in caves from June to August. Adult males fight for territories containing an average of 4 females, although they have been known to breed with as many as 12 females in a single territory.

Females give birth to a pup within a few days of their arrival, then mate 7-8 days later. After mating, females return to feed at sea for 9-13 days, after which they will return to nurse their pup for 5-6 days. This feeding cycle lasts 8-9 months, which is long compared to other fur seal species.

Conservation Status

Guadalupe fur seals are now protected by law in the United States and in Mexico, and Guadalupe Island has been designated a pinniped sanctuary.

Hopefully, this protection will restore the Guadalupe fur seal to its former range, and we will see them thrive again off the coast of California.