Pier 39's Sea Lions - Gone For Good?

Fisherman’s Wharf’s famed resident sea lions who moved into Pier 39 twenty years ago have virtually disappeared. In 1989-90, hundreds of sea lions began to show up on the docks at Pier 39 for unknown reasons. At first many viewed the colony as pests. Smelly and noisy, the sea lions took over the docks, displacing boats that had been harbored there and destroying the docks with their weight.

Nuisances aside, the marine mammals quickly became a popular tourist attraction. In winter months over the past twenty years as many as 900 sea lions typically camped out at the pier, feasting regularly on local herring.

October 2009 marked the beginning of mysterious events surrounding the sea lions. At a time of year when there are usually 200 of the animals at Pier 39, October saw a whopping surge of 1,700, for reasons no one seems to know. At the end of November 2009, the Pier 39 colony had dwindled to only 20 animals, and recently a mere handful of the animals have been seen there. The Bay Area’s Marine Mammal Center received about 1,000 starving sea lion pups in May and June of last year. This too is strange; usually the Center receives only 600 marine mammal patients in an entire year.

The mystery of our vanishing sea lions is all over the web but there’s no consensus on why they’ve left. Some scientists say that diminishing local food sources due to warming oceans have driven the sea lions north in search of food. Others refute that theory claiming that while the planet’s heating up, Bay Area ocean temperatures have remained relatively consistent. Other scientists say that while it’s normal for the sea lions to travel north in winter to hunt for food, it’s extremely odd for them to migrate in such high numbers. A fisherman who moved to the Bay Area in November 2009 has his own theory. He claims that his dog’s penchant for approaching and barking at the sea lions is what drove them away. (If so, it should be noted that laws prohibit pets from disturbing wildlife.)

By all accounts 2009 was a very difficult one for California’s sea lions. Despite normal birth rates, marine biologists estimate that about 75% of the pups born last year in Southern California’s Channel Islands starved to death after being abandoned by mothers.

Just recently, a couple of thousand sea lions have appeared off the coast of Oregon. Some scientists believe these are Pier 39’s former residents who’ve simply traveled north as they follow food sources.

Pier 39 had planned an event for January 15, 2010 to celebrate the 20th anniversary of the sea lions’ arrival. Now that stars of that party are gone, the celebration may have to be rescheduled. As the mystery continues to swirl, one thing is certain: many Bay Area residents miss the sea lions and mourn their sudden departure. No doubt tourists will miss them too.

As of now, whether the sea lions will return “home” to Fisherman’s Wharf is anyone’s guess.

Lisa-Anne Manolius is the multi- talented owner/trainer of Oh Behave! in San Francisco. A graduate of the S.F. SPCA's Academy for Dog Trainers and U.C. Berkeley's Boalt School of Law, she's available for dog behavior consultations, private training sessions, and to teach a variety of group classes. She can be reached at lisaohbehave@gmail.com.

Flickr Photo Credit: Bill Lim