An increasing number of California sea lion pups have been stranding along the coast of in Los Angeles, Orange and San Diego counties.
The number of pups needing emergency care is so great that one rescue organization has declared a state of emergency.
“We don't know what the problem is now,” said Susan Chivers, a biologist with the National Marine Fisheries Service.
“What we're seeing is a lot of skinny pups, which suggests they’re not getting sufficient nourishment, and dying of starvation."
In just three days, SeaWorld San Diego staffers rescued 11 sea lion pups that wandered ashore beaches, including one pup that was spotted sitting on the boardwalk Sunday night at Mission Beach in San Diego.
The phenomenon has been happening for nearly two weeks along beaches in Southern California, but the number of sea lion rescues has been unusually high all year, said Peter Wallerstein, director of rescue at Marine Animal Rescue in El Segundo.
"Since the beginning of the year, I've rescued 92 -- and that's a very high number," Wallerstein said in February following the rescue of a sea lion pup that wandered into an intersection in Carson, which is about six miles from the beach.
On Monday, the Pacific Marine Mammal Center in Laguna Beach declared its own state of emergency after it performed 12 rescues Saturday – a single-day record for the organization.
Marine mammal experts are beginning to discuss the problem and gather data, so they can better understand why the pups are wondering ashore this early in the year and why some are dying, Chivers said.
“There’s something going on oceanographically that there’s not sufficient food available for the moms to nurse their pups or the pups, as they’re starting to eat on their own, to find,” Chivers said.
The typical sea lion pup is round and robust. As she looked at a photo of a California sea lion pup taken recently along the coast, Chivers described evidence showing dehydration and malnourishment.
"Basically, you can see its backbone. You can see its shoulder blades," she said.
The next step for all these groups is to work together to find out why.
Part of that process will be to perform necropsies on the dead sea lion pups that have been found. Scientists are hoping that finding the exact cause of death may help them find out what is happening.
To help provide emergency care for rescued pups, the Pacific Marine Mammal Center is accepting donations, as the pups may need to stay at the center for two to four months before returning to the wild.
"With this high number of animals, we are going through our financial resources at an alarming rate," said executive director Keith Matassa.
Anyone who spots a marine mammal that might be in need of help is asked to notify a lifeguard, park ranger or the local marine mammal rescue facility.
The hotline for the SeaWorld Animal Rescue and Rehabilitation Program is 800-541-SEAL. The Pacific Marine Mammal Center is also accepting reports of stranded marine mammals at 949-494-3050.