California sea lions (Zalophus californianus) haul out on rocks like this one along the La Jolla coastline, a stretch of shoreline within the San Diego–La Jolla Underwater Park and Ecological Reserve. Adult males can weigh up to 800 pounds and are marked by a thick neck and a raised bony crest on the forehead, visible here among the smaller females and juveniles. Unlike harbor seals, California sea lions have visible ear flaps and can rotate their hind flippers underneath their bodies, letting them move on rocks with more mobility than true seals. The species is protected under the federal Marine Mammal Protection Act of 1972, which bars people from approaching or disturbing them on haul-out sites like this one.
Photo taken in November 2011.