The Guadalupe Fur Seal (Arctocephalus townsendi) is a fur seal. It is one of six members of the Arctocephalus genus, but the only one to be found in the Northern Hemisphere. 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.
Guadalupe fur seals are sexually dimorphic in size, with the males being much larger than females, although few specimens have been measured. Individuals of both sexes are dark brown or dusky black, with the guard hairs on the back of the neck being yellowish or light tan. Pups are born with a black coat similar to that of adults. Observations suggest that reproductive males are faithful to particular sites over a number of years. Tenure of territorial males lasts from 35-122 days. Births occur from mid-June through July, with most births taking place in June.
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.
The major cause of the Guadalupe fur seal's decline was commercial hunting in the late 1700s and early 1800s. The species was exterminated in southern California waters by 1825. Commercial sealing continued in Mexican waters through 1894.
No recovery plan for this species has been prepared, neither has a recovery team been established. 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 at the present time. 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.