The return of the pinnipeds - seal, sea lion, and walrus populations; includes information on viewing opportunities and volunteer protection organizations

FOR CONSERVATIONISTS, the West Coast's pinniped recovery is one of the biggest -- and least talked about -- success stories of the past 20 years. For fishermen and harbor masters, it's a mixed blessing." That's how Dr. Steven Webster of the Monterey Bay Aquarium sums up the West Coast's pinniped recovery. While much has been made of the heartening recovery of some whale species, an equally astonishing comeback can be seen in some of the whale's furry marine mammal cousins -- seals, sea lions, and walruses.

Nearly 20 years after passage of the Marine Mammal Protection Act, we're seeing pinnipeds in record populations and unusual situations -- elephant seals blanketing rookeries from the Farallons to the Channel Islands in numbers our great-grandparents couldn't have seen. At San Francisco's Pier 39, 400 California sea lions are taking over boat docks and becoming a tourist attraction. In Carpinteria, California, in sight of housing tracts, shy harbor seals are claiming a state park beach (volunteers protect them from harassment).

Conversely, some fishermen say pinniped populations are out of control, and they often watch sea lions devour fish out of nets or pick off migrating steelhead at fish ladders.

While populations of some pinnipeds are thriving, scientists are racing to study and save other species, and making surprising and disturbing finds along the way. What they've learned: elephant seals can dive deeper than most submarines; sea lions may have a kind of vocal communication; ocean pollution is suspected in new, mysterious diseases showing up in a few seals.

Some of the world's best viewing opportunities are on the West Coast. Five species are common year-round; in winter all but the walrus spend time ashore where you can see them (three more, northern fur, Guadalupe, and monk seals, are rarely seen on land). On pages 108 and 109, we list characteristics and top viewing areas.

Watching pinnipeds is more fun when you know some key behaviors. We tell what scientists have learned, where to go, how to join the rescue effort. They're federally protected -- illegal to hunt or harass; don't approach closer than 100 yards.

From the brink of

extinction

Of the eight species shown, three have seen dramatic turnarounds.

The Guadalupe fur seal is returning from near extinction -- only 14 remained in 1954. In the late 1970s, when large numbers of northern elephant seals came bellowing back to the California mainland at Ano Nuevo in San Mateo County, those seals drew major crowds and eventually got their own preserve. Their populations have nearly doubled in each of the last five years, and now the seals are being sighted at a new mainland rookery. The third species, the California sea lion, is the most visible of the big five and the most vocal; in Monterey, guest at some bayside hotels complain about the barking from a nearby colony.

The future of two species remains clouded. Although its numbers are higher now, the Guadalupe fur seal is still at risk; a major oil spill could seriously threaten its existence. The Hawaiian monk seal, estimated to number around 1,500, may be coming close to extinction.

What to watch for

Take time to watch them closely and you'll be charmed by their playful behavior and pleading, dog-like eyes. A good pair of binoculars and a field guide help. Check tide tables: in general, animals will be out feeding during the highest tides (when their haul-out sites are submerged) and resting between tides and between diving periods. Watch for individual traits and you'll capture better photographs.

First, the basics. How can you tell a harbor seal from a sea lion when you see just a head above water? Check first for external ears (sea lions have tiny ear flaps; seals don't). "Seals sink, sea lions dive" often holds true as they head back underwater. Except for harbor and monk seals, males are a third larger than females. Drawings on pages 108 and 109 highlight more features.

Next, check the flippers. These animals are called pinniped from the Latin word meaning "feather footed" because of their fan-shaped flippers, which they use mainly to propel themselves through the water at up to 35 mph. Elephant seals use their front flippers to throw cooling sand over themselves when the day heats up. Harbor seals use the long claws on their flexible foreflippers to groom.

Watch how they move. When sea lions are in the water, you may see groups of them "rafting" -- holding their flippers straight up in the air. It's a way of cooling off or warming up, letting air or sun reach the network of tiny veins in the flippers and warm or cool the blood. Unlike humans, they can't sweat, yet this way they're able to maintain a body core temperature cloe to ours under their furry skin and layer of fat.

In the water, pinnipeds are agile swimmers, but slower than whales or porpoises. They can also doze off at sea; elephant seals have been recorded at tremendous depths in a kind of torpor. You'll often see harbor seals "bottler"--asleep bolt upbright in the water with just their noses poking above the surface.