California Sea Lions show a large difference in size and weight between males and females. Males can weigh over 770 pounds while females, on average, weigh ‘only’ 220 pounds.

Males also have a prominent crest on the head (sagittal crest) which starts grow around age 5.

It is a very vocal species and males, during the breeding season, threat rivals with physical and vocal demonstrations, hence keeping them away from their females. Females and calves also have unique vocalizations among themselves.

This species is found from the southeast coast of Alaska to Mexico.