About California's Sea Lions

California Sea Lion
Zalophus Californianus

Description: The California sea lion is probably the most commonly seen pinniped along the southern California coast. It has distinct external ears, and elongated front flippers. Its hind flippers can be turned forward under its body, allowing it to walk on land. In the water California sea lions swim with powerful strokes of the front flippers. The smaller hind flippers help in steering. The male's fur is usually dark brown, nearly black when wet, and the female's is often light brown or tan; there is no undercoat. The adult male has a thick neck and a protruding forehead formed by a bony crest on the skull roof.

Size: Males may measure up to 2.4 meters (8 feet) and weigh 270 kg (600 lbs); females may measure up to 1.8 meters (6 feet) and weigh 90 kg (200 lbs.)

Range and Habitat: As the common name suggests, this species occurs mainly in California's coastal waters, but is also found around the Galapagos Islands and Japan. This species ranges along the Pacific Coast, from British Columbia south to California and the coast of Mexico. The breeding range of Zalophus extends from the Channel Islands off southern California south along the coast of Mexico, possibly to the Tres Marias Islands.
A number of islands in the Sea of Cortez have breeding populations, but the major sites are San Miguel and San Nicolas islands in the Channel Island chain, along with several islands off the Pacific Coast of Baja California. Towards the end of the breeding season, both adult and immature males start moving north from the west coast of Baja California and the Channel Island rookeries. This migration peaks in September along central and northern California.

Behavior: Along the California coast, Zalophus can be seen on offshore rocks, quiet beaches, in bays, and sometimes on buoys. It's gregarious and curious, and will investigate swimmers and scuba divers. It can swim up to 16 kmph (10mph) when after food.

Reproduction: Females may breed at three years, males at five. The breeding season takes place between May and July. During the breeding season, dominant bulls establish beach-front breeding territories that they protect by barking at or moving aggressively towards intruding males. Occasionally, bulls engage in combat. Mating takes place on the beach or in the water. After a year-long gestation period, a single pup is born. They are weaned after several months, but may continue to nurse for up to a year.

Diet: California sea lions eat fish, mollusks, and crustaceans.
Predators: Orcas, great white sharks, and humans.

Conservation Status: Although the California sea lion is not considered an endangered species, it is protected in U.S. waters by the Marine Mammal Protection Act.

This educational information was provided to Hornblower Cruises & Events for our guests on the NEW Harbor Cruise & Sea Lion Adventure in partnership with the San Diego Natural History Museum located in Balboa Park of San Diego www.sdnhm.org. For more information about California sea lions visit the Marine Mammal Center web site at www.tmmc.org.