Arctocephalus townsendi

(Merriam, 1897) - Guadalupe fur seal

Distinctive Characteristics

Guadalupe fur seals have a thick pelage, with dense underfur. The forehead is flattened to slightly convex. Adults have moderate length whitish cream vibrissae and long prominent ear pinnae. The foreflippers have pelage that covers the black leathery skin on the upper surface, well past the wrist. The hindflippers are moderately long. The toes of the hindflipper are all approximately the same length; the hallux is only slightly wider and thicker than the other digits. Adult males have a very long, flat-topped, pointed muzzle with a large bulbous nose with downward pointing nostrils (they can have a shark-like silhouette). Adult males develop a mane of long coarse guard hairs that cover the neck. This area is also thickened and more muscular in bulls.

Coloration of adult males is dark greyish brown to greyish black. The longer guard hairs of the mane may be light tipped, yielding a greyish grizzled appearance. Much of the head and back of the neck often appears tan to yellowish, whereas the throat and underparts of the neck are darker. Coloration of adult females is dark grey-brown to greyish black above, variably paler below (especially on the chest and underside of the neck, which can be creamy grey). There may be areas of lighter colour on the face.

The dental formula is I 3/2, C 1/1, PC 6/5.

Can be confused with

Three other otariids, the northern fur seal and California and Steller sea lions, share the present range of the Guadalupe fur seal. The Guadalupe fur seal can be distinguished from them by head shape, ear size, hindflipper length, and coloration differences. Note the differences between the amount of fur on the foreflippers between Guadalupe and northern fur seals.


Two adult males were about 1.8 and 1.9 m in length and the latter specimen was estimated to weigh 160 to 170 kg. Two adult females were about 1.2 and 1.4 m; the latter was estimated to weigh 45 to 55 kg.

Geographical Distribution

Guadalupe fur seals have a relatively small core range. At present, the only place they are known to breed is on Guadalupe Island off central Baja California, Mexico. Males are now regularly seen on San Miguel and San Nicolas Islands of southern California. They are also occasionally sighted at sea in the Southern California Bight, and on beaches in central and northern California. The pelagic distribution of this species is unknown. When ashore, Guadalupe fur seals prefer volcanic caves and grottos, or other rocky habitats. The former range of this species was apparently much more extensive.

Biology and Behaviour

Breeding and pupping in this species are from mid-June to August; most pups are born from the middle to the end of June. Females with pups and subadults may be seen on or around the island throughout the winter and into the spring.

Knowledge of activities and behaviour at sea, away from Guadalupe Island, are limited to a handful of records. At sea, they appear to be mostly solitary. Observations of animals in captivity suggest that they spend much of their waking time grooming. They raft at the surface to rest in the characteristic “southern fur seal” head-down posture. They also float with 1 or more flippers extended out of the water. When traveling rapidly, they have been observed to porpoise.

Feeding activities and food habits are nearly unknown.


Guadalupe fur seals were nearly exterminated by humans in the 19th Century, and by the turn of the century the species was considered extinct. Following the observation of several dozen fur seals on Guadalupe Island in 1926, and the collection of 2 animals for the San Diego Zoo in 1928, none were seen again until 1949 when a lone bull landed on San Nicolas Island. A 1954 search of Guadalupe Island found 14. A count from 1987, yielded 3259 animals including 998 pups. Guadalupe Island has been a protected pinniped sanctuary since its designation by the Mexican government in 1975. These fur seals are fully protected under Mexican law.

IUCN Status