SANTA CRUZ — An overabundance of sea lion pups and an apparent lack of food has local animal rescuers racing to save them.

“We haven’t seen anything like this outside of an El Niño year,” said Shelbi Stoudt of the Marine Mammal Center in Moss Landing.

Local marine animal experts are searching for answers.

“They get the live ones and we get the dead ones,” said Teri Sigler at Long Marine Lab in Santa Cruz. “We’re doing necropsies to try to solve the questions of what’s going on. Why are they here and why are they dying? And there is the question of whether another El Niño is coming.”

El Niño is the unseasonable warming of the Pacific Ocean off South America. The phenomenon changes the climate by causing more rain than normal in the Southwest, and less precipitation in the Northwest, said Bob Benjamin of the National Weather Service Office in Monterey. El Niños also can result in fewer bait fish and other marine life eaten by sea lions.

Not surprisingly, there also tends to be an increase in female sea lions and pup deaths during El Niño years, according to the National Marine Fisheries Service. After birth, sea lions nurse for about 10 months before being let loose to hunt and feed on their own, Stoudt said. Sea lions are “opportunistic eaters,” meaning the carnivores will eat when food, which consists of perch, squid, herring and other fish found close to shore, is available.

The Sausalito-based Marine Mammal Center, which also has offices in Moss Landing and Morro Bay, has been rescuing 10 to 15 sea lions daily. The Central Coast facilities are operating as holding zones for sick and injured sea life, because the center’s newly opened hospital in Sausalito is at capacity, she said.

Numerous pups have been hanging around the rocks at Lighthouse Point in Santa Cruz, and around the Municipal Wharf. Numerous pup carcasses also have washed up on county beaches.

Year to date, the Marine Mammal Center has helped nearly 200 sick and injured sea lions stranded on Santa Cruz County beaches, many pups, Stoudt said. That’s more than double the 78 stranded animals rescued around the same time last year. All sea mammals combined, the center has helped about 470 this year, compared to 325 last year at this time. Annually, the center sees about 600 sea mammals.

There are roughly 240,000 sea lions living along California’s coast, according to the National Marine Fisheries Service. Regardless of the sea lion pup deaths, there appears to be no drop in the overall sea lion population, center officials said.

While the Marine Mammal Center’s staff is able to release many of the marine mammals back into the wild, some die while in their care, she said.

“The pups are usually so malnourished by the time we get to them, that their stomachs atrophy,” she said.

Sea lions range from Vancouver, British Columbia, to Baja California. They can live about 30 years with males growing up to 7 feet long and weighing 860 pounds. Females grow up to 6 feet in length and weigh 220 pounds, according to the center’s Web site.

Sea lions give birth to one pup at a time in May and June, Stoudt said. The pups seen sunning themselves in Santa Cruz are last year’s births, many of which were low weight when they were born, Stoudt said.

While pups are curious and not afraid of humans, people should stay away, she said.

“Do not feed them or pet them or wrap them in blankets,” she said. “One was found Saturday in the Monterey Harbor. People had been feeding it burritos, hot dogs and dead rays.”