What is taxonomy?
California sea lions are playful, smart, and graceful in the water. The trained "seals" in zoos and aquariums are often California sea lions because they are intelligent, agile and easy to train.
Young male and female California sea lions look very similar with blond or light brown fur, but when males reach 4 or 5 year old, their fur changes to a dark red or chocolate brown color and they develop a blonde patch on top of their head as they age. Adult males may be up to 8 feet long and 1,000 pounds. California sea lion females are blond to dark brown. Females maybe over 5 feet long and weight up to 220 pounds. Pups are dark brown at birth and weigh about 16 pounds. When pups are 4 or 5 months old they molt their dark brown coat for a light brown or silver coat.
California sea lions are very social on land and in the water, but during the breeding season the males will aggressively defend their territories and females will fight other females to protect their pups. While on the breeding islands, California sea lions are very skittish of humans and will run into the water if they see or smell people.
- The number of California sea lion pups born each year has almost tripled since 1975!
- California sea lion males are larger than females. Males may weigh up to 1,000 pounds and females may weigh up to 220 pounds.
- California sea lion males bark like a dog to communicate with other males and females. Females and pups communicate using vocalizations that are unique to the female and pup. Each pup and female have a unique scent that also identifies them. A female can locate her pup among hundreds of physically identical pups by her pup's vocalization. When she finds her pup she smells the pup as a final check that the pup is hers.
- California sea lions separate their nursing and feeding activities. They nurse their pups for 1 to 2 days and then leave the pup ashore while they travel to feeding areas at sea. They spend 2 to 5 days feeding and then return to nurse the pup. During the mother's absence, the pup fasts. Females continue a pattern of going to sea for several days and nursing ashore for several days until they wean their pup. Females nurse their pups for almost a year!
- California sea lions feed on fish and squid near the ocean surface down to 80 feet but can dive to depths greater than 500 feet. Their dives are usually about 3 to 5 minutes long. They may dive continuously for up to 30 hours.
- Male California sea lions migrate during the winter to feeding areas off California, Oregon, Washington and British Columbia, Canada, but females and pups remain at the breeding colonies until the pup is weaned.
What I should know about California sea lions!
- Where do California sea lions live?
- How many California sea lions are there?
- How can I identify a California sea lion?
- What do California sea lions eat?
- How do California sea lions have their young?
- How long do California sea lions live? How do they die?
- Where can I find more information about California sea lions?
California sea lions can be found from southern Mexico, north to southwestern Canada. They breed on the Channel Islands off California, and on islands on both coasts of Baja California in Mexico.
The population, in 2001, of California sea lions is estimated to be 200,000!
Males are dark grayish brown to black coat as well as a recognizable crest on their forehead, which becomes larger with age. Females have a light brown coat. The California sea lion also has a long snout giving it an almost dog-like face. Adult male California sea lions measure up to 8 feet in length and weigh an average of 800 pounds, while adult females measure an average of five feet in length and weigh 200 pounds. The pups of California sea lions will weigh about 16 pounds at birth.
The main diet of California sea lions consists of anchovies, sardine, whiting, mackerel, rockfish and market squid.
Each year between May and early August, males and females aggregate at the breeding colonies to breed and give birth. Males establish territories and pregnant females give birth to a single pup in May or June in the territories. After nursing the pup for 5 to 8 days, the female leaves the pup for her first feeding trip. She feeds for 2 to 5 days and then returns to nurse the pup for 1 to 2 days. The female alternates feeding trips with nursing visits until the pup is weaned. Females nurse their pups for 6 to 11 months. California sea lions are the only species of pinniped that separates pupping and breeding activities in time. Breeding occurs 30 days after the female has given birth and occurs in July and early August.
It is unknown how long California sea lions live in the wild, but in captivity they may live up to 24 years. The age of California sea lions can be determined by extracting a canine tooth after they die and reading annuli that represent periods of growth of the animal over time (like aging a tree by tree rings).
California sea lions have no land predators but Great White sharks and Killer whales eat California sea lions in parts of their range. Pesticides and entanglement in fishing gear may also contribute to the mortality of California sea lions. Environmental events such as El Niño events can result in temporary declines in pup births and high mortality of pups and juveniles.
- Marine Mammal Laboratory
- Office of Naval Research
- Seal Conservation Society
- University of Michigan - Museum of Zoology
- The Marine Mammal Center
This portion of the MML website is intended for a student audience and their educators.
Information within the education website should not be cited in scientific journals or publications.