A seafood bounty lures sea lions to S.F.'s Pier 39 in numbers not seen in 15 years

The echoes of barking and blubber-slapping have grown louder in San Francisco's Fisherman's Wharf.

An unusually large herd of sea lions hauled out of the bay waters to hang out on the docks at Pier 39, a popular tourist destination. It's the most sea lions the area has seen in 15 years, according to pier officials.

Over 1,000 sea lions were counted this week, Pier 39 harbormaster Sheila Chandor told multiple media outlets.

A bounty of anchovies and herring in the bay waters has drawn the pinnipeds to feast ahead of mating season, which starts next month, Chandor told SF Gate.

"It's all about the food," she told the Associated Press. "They are fueling up for the mating season. It's spring. They are ready to rock and roll down in the Channel Islands, and we're a nice pit stop with some great seafood."

'Sentinels for the sea'

The sea lion surge is generally a good sign of the animal's strong population and the health of its habitat, Adam Ratner, the director of conservation engagement at the Marine Mammal Center in Sausalito, Calif.

California sea lions serve as "sentinels for the sea," Ratner said. "Their population kind of reflects the health of the ocean. So seeing big numbers of California sea lions is obviously a great thing."

The bigger picture of the ocean's ecological health is harder to gauge. Because climate change can drive fish populations to relocate, Ratner said, the seafood buffet in the San Francisco Bay doesn't mean there's more fish overall.

"We see the fish stock shifting and moving into different places," he said. "It's not necessarily that we're seeing more fish, but the fish are going into different areas."

In recent years, the pier's sea lion population has hovered around 300 to 400 during the winter and up to 700 in spring, Chandor told the AP.

A sea lion hangout since 1989

The slippery residents have been a star attraction for tourists for almost 35 years. The waterfront has emerged as a hot spot for the mammals in 1989.

That fall, the docks at Pier 39 had just finished being remodeled, but the boats hadn't moved back in yet. That's when the sea lion invasion began.

"You had this open real estate essentially in downtown San Francisco that a couple of sea lions saw and said, hey, wouldn't this be a great place to rest and relax?" said Ratner.

The sea lion crowd grew from a handful that September to about 150 by January 1990, Ratner said. Their surprise arrival both drew fans and created enemies. Some marina residents and workers were put off by the stench and noise of their new neighbors, while others saw the animals as a bright spot after the devastating Loma Prieta earthquake, SF Gate reported in 2019.

Pier 39 officials turned to the Marine Mammal Center to figure out what to do about the sea lions. The final decision, Ratner said, was to let the sea lions stay and coexist with humans.

"It's really turned out to be a great thing," he said. "It's just a testament to how we can actually work together to think about how do we share our shores, essentially, with marine mammals and other wildlife in a way that benefits all the parties involved?"