There are six species of sea lion: Steller's, Australian, South American, New Zealand, Galapagos and California (another, the Japanese sea lion, went extinct in the 1950s). Sea lions have external ear flaps, which distinguish them from true seals which are earless. Sea lions are also characterized by long fore-flippers, the ability to walk on all fours and short, thick hair.
The California sea lion is found along the coast of North America from southeastern Alaska (from about Icy Bay - just south of where the western Yukon border is) down to about Acapulco, Mexico. The breeding range is much smaller, from the top of northern California south to about Mazatlan, including the Gulf of California. They breed from May to August and in non-breeding season the males migrate to the northern ends of the range to feed and the females stay nearer the breeding grounds.
|Sea lions basking on rocks in Yaquina Bay, Oregon.|
|Basking on docks and swimming. It seemed like the males had most of the choice dock spots and the females swam around in the water.|
Males are substantially longer and heavier than females, around 7.9 feet long compared to 5.9 feet, and 770 pounds compared to 220 pounds. Males also have manes and thicker necks, chests and shoulders and a protruding crest that gives them a domed forehead.
|Large male California sea lions.|
|Female sea lions. Note the outer ear flaps.|
They eat squid and fish and sometimes clams and they are eaten by killer whales and sharks, particularly great white sharks.
|A swimming female.|
|A sleeping male. Note what appear to be battle marks.|
|A barking male.|
While we were in Newport, Oregon in January, in Yaquina Bay, we found a huge number of California sea lions on the docks and on the nearby breakwaters, with extremely loud barking and grunting. We could hear them from several miles away.
|Seals on a breakwater with Yaquina Bay Bridge in background.|
I have always associated the California sea lion with the female. It seems like that is what is always in zoos and what I have typically seen on rare occasions in Mexico and California. In Oregon, males seemed to predominate which is consistent with them being outside of the breeding range during non-breeding season.