California Sea Lion (Zalophus californianus)
California Sea Lion
Photo: NMFS National
Marine Mammal Laboratory
Did You Know?
· California Sea Lion Unusual Mortality Event declared in southern CA.
Video: What do California sea lions eat? How do we find out?
Credit: Alaska Fisheries Science Center, NOAA Ocean Media Center
MMPA - California sea lions, like all marine mammals, are protected under the MMPA.
|Weight:||700 pounds (315 kg) for males, but can exceed 1,000 pounds (455 kg);
240 pounds (110 kg) for females
|Length:||7.5 feet (2.25 m) for males;
6 feet (2 m) for females
|Appearance:||dark brown with broad foreflippers and a long, narrow snout|
|Diet:||squid, anchovies, mackerel, rockfish, and sardines|
|Behavior:||social animals, they form groups of several hundred individuals onshore;
fast, agile swimmers;
deep divers, up to as much as 1,760 feet (535 m) deep
California sea lions are members of the "eared seal" family, Otariidae. They are the most recognized pinniped species, because they are commonly seen doing acrobatic tricks in shows at zoos and aquariums.
Male California sea lions have a robust body while females and juveniles have a more slender body. They have broad foreflippers and a long, narrow snout. Males have a broad forehead. Their coats are dark brown with females being slightly lighter in color.
California sea lions are sexually "dimorphic" with males reaching average lengths of 7.5 feet (2.25 m) and weighing about 700 pounds (315 kg). Some large males exceed 1,000 pounds (455 kg). Females are much smaller, reaching average lengths of 6 feet (2 m) and weighing about 240 pounds (110 kg). They have a lifespan of 20 to 30 years.
California sea lions are social animals and form groups of several hundred individuals onshore. They are fast, agile swimmers and are often seen porpoising and wave riding. The deepest dive ever recorded for a California sea lion is 1,760 feet (535 m).
Males are "polygamous" establishing breeding territories that may include up to fourteen females. They defend their territories with aggressive physical displays and vocalization. Sea lions reach sexual maturity at 4-5 years old. Breeding season lasts from May to August while most pups are born from May through July. Three weeks after giving birth, females are ready to mate again. Pups are weaned at 10 months old.
California sea lions feed mainly in upwelling areas on a variety of prey such as squid, anchovies, mackerel, rockfish, and sardines. They also take fish from commercial fishing gear, sport-fishing lines, and at fish passage facilities at dams and rivers.
California sea lions reside in the Eastern North Pacific Ocean in shallow coastal and estuarine waters. Sandy beaches are preferred for haul out sites. In California, they haul out on marina docks as well as jetties and buoys.
California Sea Lion Range Map
(click for larger view PDF)
California sea lions range from the Pacific coast of Central Mexico north to British Columbia, Canada. Their primary breeding range is from the Channel Islands in Southern California to Central Mexico. There is one stock of California sea lions in U.S. waters that ranges from the U.S./Mexico border and extends to Canada.
The abundance of the U.S. stock of California sea lions is updated in the most recent stock assessment report. The population has been increasing since at least 1975.
- incidental catch and entanglement in fishing gear, such as gillnets.
However, estimated and reported levels of fishery-related mortality are so low that they likely have an insignificant impact on the population.
- biotoxins, as a result of harmful algal blooms
- gunshot wounds and other human-caused injuries, as California sea lions are sometimes viewed as a nuisance by commercial fishermen
California sea lions are classified as Low Risk-Least Concern on the IUCN Red List .
This species is protected under the Marine Mammal Protection Act of 1972, as amended.
|Stock Assessment Reports||n/a||various|
- NOAA authorized WA, OR, and ID to remove California sea lions that threaten protected salmon in the Columbia River Basin
- NMFS National Marine Mammal Laboratory California Sea Lion Information and Research
- NMFS Southwest Fisheries Science Center California Sea Lion Information
- NMFS West Coast Regional Office Safely Deterring Seals & Sea Lions [pdf]
- NOAA's National Marine Sanctuaries
- Ocean Biogeographic Information System (OBIS-SEAMAP) California Sea Lion Species Profile
Updated: May 15, 2014