Sea lion pups cannot find enough food off Southern California, so they're coming ashore emaciated. Many are dying and the more fortunate mammals are ending up at overwhelmed care facilities intent on feeding and ultimately releasing them.According to CBS News, about 100 sea lions are rescued on California beaches annually. More than 700 have been rescued so far this year. Most are recently-weaned pups.
"They're very sick," said Keith Matassa of the Pacific Marine Mammal Center in Laguna Beach in Orange County.
The facility, one of a handful from Santa Barbara to San Diego, has rescued more than 130 sea lions, which is a record for the first three months of a calendar year.
"A normal sea lion at this age—8 to 9 months old—should be around 60, 70 pounds," Matassa said. "We're seeing them come into our center at 20 to 25 pounds, and they really look like walking skeletons."
"It boils down to these pups are not getting enough food to survive on their own," Dave Koontz, a spokesman for the facility, told the San Diego Union-Tribune. "After they are weaned from their mothers, the food is not there or [is] at a depth they can't reach."
Sea lions prey on small fish, including schooling bait fish such as anchovies and sardines. Mysteriously, these bait fish have been scarce for much of the winter and perhaps this caused adult sea lions to wean their pups prematurely.
What's worth noting, however, is that the sea lion population off California and the U.S. West Coast is robust, perhaps at or beyond carrying capacity. Sea lion numbers have skyrocketed since the Marine Mammal Protection Act was enacted in 1972, and the most recent population estimate, in 2008, was 297,750. This is just the U.S. (West Coast) stock, and does not include Mexico or Baja California.
The primary breeding and nursing grounds are the northern Channel Islands, and the highest concentration of sea lions is in Southern California.
Bait fish have been scarce for much of the winter off the Channel Islands, according to fishermen. Hence, wayward pups are finding their way ashore from Santa Barbara to San Diego.
I encountered a pup Sunday afternoon while walking just north of Swamis Beach in Encinitas (pictured at right). The skinny mammal was 40 yards from the water, climbing on boulders and falling between cracks in the rocks. I telephoned the SeaWorld stranding hotline and left a message, which was not returned. I assumed the facility was simply overwhelmed, so I continued my walk, hoping the sea lion would somehow survive, but realizing it probably would not.
--Top image is courtesy of the Pacific Marine Mammal Center. Second image, showing a stranded sea lion at Swamis Beach, is by Pete Thomas