Four times more sick and dying sea lion pups have gotten stranded on California beaches this year, and experts say unusually warm ocean water along the West Coast is to blame.
Officials with the National Oceanic and Atmospheric Administration said Wednesday about 940 sick and starving young sea lions have washed up on California beaches so far in 2015.
That compares to about 225 sea lion strandings that officials normally would see between January and April, said Justin Viezbicke, NOAA stranding coordinator for the West Coast region. Roughly 540 sea lion pups are being treated at rehabilitation centers between San Diego and San Francisco.
Scientists say warmer coastal waters are forcing nursing mothers in the Channel Islands or Mexico to head out farther for food, leaving behind their young for longer than the normal two or four days. An estimated 300,000 sea lions live from the Mexican border to Washington state.
NOAA Climatologist Nate Mantua said the warming is likely a historical record for the northeast Pacific and the West Coast. The ocean is between 2 and 5 degrees warmer for this time of year due to the same high-pressure system that has the state in its fourth year of drought.
This is the third year that an exceptional number of pups have stranded or died.
In 2013, more than 1,500 sea lions died in California, according to NOAA figures, leading officials to declare an "unusual mortality event'' for the species. Last year, 621 pups or yearlings washed ashore on beaches.
Scientists said this year could be comparable to 2013, as more sick and emaciated young sea lions wash ashore.
The crisis could put a strain on rescue facilities, Viezbicke said. He added the public should report the strandings and never touch or transport an animal.