These shy pinnipeds can tip the scales at over 250 pounds when fully grown. Even though there are over 300,000 of them in California they are not seen as much as you would think, at least not in those numbers. Harbor Seals have no external ear flaps like the sea lions. Harbor Seals are not very agile on land because they cannot rotate their hips under themselves to walk. Excellent swimmers, they can dive to over 600 feet and stay down for up to 30 minutes. Harbor Seals do not bark and are preyed upon by orcas, sharks and, of course, in times past, man. They eat whatever they can catch preferring a diet of squid and small fish.