A wayward California sea lion named Fruitvale and five of his companions were released back into the ocean late this morning just off of the Farallon Islands.
Fruitvale, a 1-year-old sea lion, made headlines earlier this summer when Oakland police found him waddling down Interstate Highway 880. The Marine Mammal Center, a nonprofit veterinary hospital in Sausalito, has been treating him for malnourishment ever since.
He is one of hundreds of California sea lions the center is rehabilitating due to a major shortage of the schooling fish, such as anchovies and herring, which comprise the animals’ diets. These animals are coming ashore around the region in alarmingly high numbers, exhausted and looking for food.
For the past six weeks, Marine Mammal Center workers have been releasing some of these rehabilitated yearlings back into the ocean. The 45 sightseers who bought tickets for today’s SF Bay Whale Watching Cruise to the Farallon Islands were surprised to discover six sea lions in plastic carriers would be coming along as well.
The ship’s captain, Joe Nazar, lets the center use his cruises to return sea lions to the Farallones where food is more abundant and human contact is minimal.
Fruitvale and company endured choppy waters to arrive at the Farallones around 11:30 a.m. Here Nazar and Trish Mirabella, an educator at the center, gave visitors and unanticipated lesson in marine science. Nazar must participate because by law the ship’s captain is the only one who can open the gates on the side of the boat.
One by one, he and Mirabella positioned each plastic carrier at the open gate and released the door, allowing Fruitvale, Anquet, Hondo, Metheny, Prelude, and Superstar to dive head first into the ocean and swim away.
Heidi Andrews and her family came into San Francisco from Livermore for the seven-hour whale watching cruise. The surprise sea lion dispatch “was the best part of the day,” she said.
“We watched them all come out,” she said. “They all stuck together as they swam off.”
The sea lions were rescued between June 22 and July 5, from points including Fort Baker to as far south as Pismo State Beach near San Luis Obispo, according to the center. In the past six weeks, seven boats have ferried sea lions to the Farallones.
Fruitvale was one of the luckier sea lions, said Marjorie Boor, a volunteer with the Center. He was underfed, but was not suffering from the abscesses or fishing line injuries that plague other sea lions searching for food.
“He pretty much got to hang out and fatten up,” she said. Year-old sea lions usually weigh about 50 kilograms, or 110 pounds. The sea lions released today weigh 15 to 20 kilograms, she said.
Workers at the center have been feeding sea lions through tubes, Boor said, a difficult proposition since the animals have teeth.
This desperation for food also causes other health problems. Metheny the sea lion still has scarring around her neck from an encounter with fishing line. She was so hungry she most likely went after a fisherman’s bait, Boor said.
The lack of fish, coupled with a larger-than-average sea lion birth rate last year, means one-year-old sea lions are having trouble finding food when they leave their mothers to make room for the new crop of babies. Yearling sea lions are coming ashore all over the Bay Area emaciated, malnourished and sometimes injured.
“They’re just walking out of the surf and collapsing,” Boor said.
“There’s a crisis going on.”
The Center typically sees about 700 animals a year, mostly sea lions, elephant seals and harbor seals. So far more than 1,000 animals have come to the Center this year, and more than 700 are sea lions. Staff and volunteers are struggling to keep up, and many animals are too far gone to be saved, Boor said.
Warmer ocean temperatures are wreaking havoc on the food supply in several ways, according to Bob DeLong, a marine biologist with National Marine Mammal Laboratory in Seattle. The strong winds that typically “upwell” colder deep-ocean waters to the ocean surface ceased in late May, he said.
This creates a scarcity of phytoplankton, he said, which causes problems higher up on the food chain
Without this colder, nutrient-rich water, there is less phytoplankton at the ocean’s surface and in turn, less fish for sea lions to eat, according to DeLong. The warmer water also drives existing fish away as they seek colder temperatures farther out at sea.
Additionally, the West Coast has just entered into El Nino conditions, expected to raise water temperatures even further in three or four months.
“It could get a whole lot worse, but we don’t know how strong it’s going to be,” he said.