The national Oceanic and Atmospheric Administration announced on Tuesday that so far in this year they have spotted eighty Guadalupe fur seals stranded on the California coast. It said the sightings are far above the average of 10 to 12.

The agency said when they spotted the seals 42 of them were dead, 38 alive, but only 11 of them lived to be rehabilitated and released. When found most of the seals were emaciated.

NOAA declared that strandings is an unusual mortality event. It also made a similar declaration for California sea lions in 2013, but officials said numbers of sea lions stranded this year are returning to normal.

Both the species have different habits and ranges, but both may be suffering from changes in the availability of food because of warmer Pacific waters, said officials. Guadalupe fur seals, once brought to the brink of extinction by commercial hunting, now number around 15,000, officials said.

Guadalupe fur seals breed almost exclusively on the Mexican island of Guadalupe, but range as far north as Vancouver Island.

Scientists are studying ocean-warming trends to figure out why endangered Guadalupe fur seals are stranding themselves and dying in alarming numbers along the central California coast.

The majority of the stranded seals were pups born last year, but at least four were adult females, said Tenaya Norris, a scientist at the Marine Mammal Center in Sausalito, where most of the animals were rehabilitated.

“We think that warm water conditions have really changed the range of quite a few of the forage fish species that the fur seals would be going after,” he said.

“We don't know a lot about their diet,” she said, “but from what we do know it looks like they primarily eat squid. It might be that the squid have moved to different locations or that there is not a lot of it.”