- Common Name:
- California sea lion
- Scientific Name:
- Zalophus californianus
- Type:
- Mammals
- Diet:
- Carnivore
- Group Name:
- Herd, raft
- Average Life Span:
- Up to 30 years in the wild
- Size:
- Up to 8 feet
- Weight:
- Up to 1,000 pounds
- IUCN Red List Status:
- Least concern
- Current Population Trend:
- Increasing
What is a California sea lion?
California sea lions often live close to people. They gather in shallow waters, beaches, and manmade structures like docks, buoys, and jetties on the western coast of North America, along the Pacific Ocean.
These marine mammals from the seal family, or pinnipeds (meaning “fin-footed” in Latin), can be identified by their ear flaps, large front flippers, and strong rear flippers that rotate under their body, allowing them to “walk” on land. You’ll also hear them—they gather in herds and bark like dogs.
Adult females and pups are slender-bodied and are lighter in color (blonde to tan), while adult males are generally larger and mostly dark brown to black. These sea lions are intelligent and trained easily, which is in part why they’re commonly seen in zoos and aquariums.
California sea lions eat a variety of prey found in coastal waters, including squid, anchovies, mackerel, rockfish, and sardines. Though the sea lions aren't eating the toxic algae directly, bad algae gets in their bodies by accumulating in the fish they eat.
Social behavior and reproduction
California sea lions are very social, gathering in groups up to 1,500. They like to rest packed on top of each other on beaches, docks, and jetties, but will also float together in the ocean in groups called “rafts.”
They’ve even been seen interacting with other pinnipeds, like harbor seals and Northern fur seals.
The animals return to their rookeries (breeding grounds) in central and south California annually, where females give birth to pups in early summer. Mothers carry pups for around nine months, like humans. Each mother will usually give birth to only one pup.
Newborns weigh 13 to 20 pounds and stay with their mother for about a year to nurse and learn how to swim and find food. Mothers and pups identify each other through smell and vocalizations.
Conservation
California sea lion populations has been increasing since at least 1975. Like all marine mammals, they are protected under the Marine Mammal Protection Act.
However, humans still pose a major threat. For example, these sea lions often get caught in fishing gear. Once entangled, they may drag the gear for long distances, causing fatigue and injury, compromising their ability to feed. This may result in inability to breed or death.
California sea lion populations have also been affected in recent years by ecological changes, often connected to climate change and pollution. These can result in a decrease in prey resulting in malnutrition, poisonous algal blooms, and infectious disease have also affected California sea lion populations in recent years.
Being easily accessible for humans is also dangerous. When people illegally try to feed them, it changes their natural behaviors, making them less wary of people and boats. They also may associate people with an easy meal, which poses a problem for fishermen who don’t want them near their boat.
It is important to view these wild animals from a safe and respectful distance for their safety—and yours. If you see a sick or injured seal or sea lion, please call your nearest marine mammal rescue organization.
DID YOU KNOW?
— NOAA Fisheries
California sea lions have been seen surfing breaking waves—just like humans, without a surfboard.
— The Marine Mammal Center
California sea lions can regulate their body temperature through capillaries in their fins. When their fins warm or cool, the effect spreads through their body.
— Dolphin Research Center