1. California sea lions are social animals. They can be seen resting close together at chosen "haulout" sites or floating together on the ocean surface in groups called "rafts."

2. Sea lions, fur seals, seals and walruses are collectively called pinnipeds, Latin for "feather feet." Their streamline bodies and flippers allow them to move quickly through sea water which is eight hundred times denser than air.

3. California sea lions are opportunistic feeders, feeding on whatever is available including squid, octopus, herring, rockfish, smelt, hake and lampreys.

4. During the breeding season of June and July, California sea lion males establish and protect territories, both on land and in water. The best territory is one where many females come to give birth.

5. California sea lions are known for their intelligence, playfulness and noisy barking. (trained "seals" in zoos and aquariums are usually sea lions.)

6. The California sea lion is a member of the eared seal family of Otariidae because they have visible external ear flaps and the ability to rotate their hind flippers forward, walking on all flippers on land.

7. Although the California sea lion is not an endangered species it serves as an indicator to scientists of the health of the ocean. The more we learn about California sea lions the better able we are to help other threatened species like the Steller sea lion.

8. To tell mature California sea lion males from females, look for the bump or "crest" the males develop on their heads around five years of age. As males get older the fur on the crest and around their whiskers gets lighter.

9. Adult male California sea lions can reach 1,000 pounds in weight and 7 feet in length. Adult females can grow to 350 pounds and 6 feet in length.

10. Despite their name, California sea lions look more like dogs than lions. What's more, they "bark" and their young are called pups.

11. The body of a sea lion is so pliable that they can practically bend over backward and touch their nose to the tips of their back flippers.

12. Killer whales and great white sharks are the California sea lions greatest natural predators. However man contributes to sea lion deaths through ocean pollution, illegal shooting and entanglement in nets.

13. California sea lions may be mistaken for dolphins when they "porpoise," or jump out of the water, to make faster time swimming. Young sea lions are often seen riding waves alone the shore like human body surfers.

14. California sea lions range along the Pacific Coast from Vancouver to the southern tip of Baja. Years ago there was also a population off the coast of Japan. Unfortunately it was hunted to extinction.

15. California sea lions usually breed on offshore islands from the Channel Islands near Santa Barbara to Mexico. They occasionally breed on Año Nuevo and the Farallon Islands in Northern California.

16. Unlike other marine mammals, seals and sea lions can live for long periods both in the ocean and on land. They hear relatively well both in air and underwater.

17. Sea lions vs. seals, how can you tell the difference? Sea lions have visible external ear flaps, and walk on their flippers while on land. Seals have small ear holes and they crawl on their bellies on land.

18. Special contracting nose muscles allow California sea lions to seal their noses closed. They can remain submerged for 10 to 15 minutes, but sea lions are mammals so they must surface for air.

19. California sea lions coexists with PIER 39's marina tenants, thanks to management's thoughtful decision to vacate "K" dock, leaving the sea lions undisturbed.

20. You can help sea lions (and seals and sea otters and whales and dolphins) by becoming a member or a volunteer of The Marine Mammal Center located near Sausalito in the Marin Headlands.

21. Even on crowded rookeries, where thousands of sea lions congregate, California sea lion females and pups recognize each other mainly through smell and vocalizations.

22. California sea lion pups are born in June or July. They weigh 12 to 14 pounds at birth and nurse at least 5-6 months, sometimes up to one year. Pups have never been observed at PIER 39.

23. Like human hands, seal and sea lions flippers have five skeletal digits. However at a distance these digits are not always visible in sea lions. The front flippers of seals do have five visible claws.

24. No one really knows why the first group of California sea lions began "hauling" out on PIER 39's "K" dock in 1990, but the abundant food supply in the ocean and the protected environment keeps them coming back year after year.

25. California sea lions are various shades of chocolate brown. Pups are born with a black coat, after about three weeks they grow their brown fur which they will lose or molt every year. Males are usually darker in color than females.

26. California sea lions are polygamous. A mature male may breed with 3 to 40 females in a season, depending on his size and strength.

27. California sea lions are warm-blooded animals with a thick layer of blubber to insulate them against the cold. Their short fur mainly serves to protect their skin when "hauling out" on rocks.

28. Sea lions and seals tear profusely to cleanse their eyes of excessive salt and other impurities. They do not cry. They see much better underwater, on land they are somewhat nearsighted.

29. California sea lions in the wild may live up to 18 years. Those in captivity have been known to live 23 years or more.

30. Years ago there were two types of sea lions found off San Francisco - the California sea lion and the Steller sea lion. The Steller sea lion, which is twice the size of the California sea lion, is a threatened species and now rarely seen in our area.

31. California se lions can swim up to 25 mph in short bursts. They often dive to depths of 360 feet, with recorded maximum dives reaching 800 feet.

32. Since they're animals of habit, it's a good bet (but not a sure thing) that the California sea lions will keep returning to PIER 39's "K" dock.

33. California sea lions are protected by the Marine Mammal Protection Act. It is unlawful for unauthorized persons to feed, handle or harass them.

34. Like humans, sea lions and other marine mammals can develop diseases such as pneumonia, cancer and epilepsy.

35. One of the biggest dangers to sea lions today is becoming entangled in plastic pollution. Please cut six-pack rings and any plastic that forms a ring, before throwing it away.

36. Sometimes a spotted harbor seal will "haulout" with the California sea lions at PIER 39. The sea lions always rest a few feet away, giving the seal "its space."

37. California sea lions will bite if provoked. Don't ever approach a beached sea lion or seal. If you think you have found a marine mammal in distress, call The Marine Mammal Center at 415.289.7325.

38. All sea lions and fur seals propel themselves through the water using their long front flippers. Their back flippers act as stabilizers and are not used much in swimming.

39. PIER 39 has enlisted the expertise of The Marine Mammal Center to help our visitors know more about the California sea lions. Visit The Marine Mammal Store and Interpretive Center located at PIER 39, on the 2nd level near where the sea lions "haulout."

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