stranded sea lion in California
This sea lion pup was rescued in San Clemente and taken in by the Pacific Marine Mammal Center in January, 2015. He was malnourished and dehydratedThe Pacific Marine Mammal Center

More than 1,450 starving sea lion pups have been washed ashore along beaches in California so far this year in what experts are calling one of the worst stranding events in recent history.

The Pacific Marine Mammal Center is one of many rescue centres being inundated with calls about lost, emaciated sea lions – with some reports predicting the number of pups could be closer to 1,600.

It is not uncommon for sea lions to wash ashore each spring as pups leave their mothers, but the number of stranded babies this year is five times greater than in 2013.

"These animals are coming in really desperate. They're at the end of life. They're in a crisis," said Keith A Matassa, executive director at the Pacific Marine Mammal Center.

"And not all animals are going to make it."

Experts blame the shortage of food on waters being unusually warm – two to five degrees up – for this time of year, which is forcing prey away from where the sea lions breed and wean their young. Mothers are then spending their time away from their pups as they hunt for food, leaving them stranded and often washed up along the beaches from San Diego to San Francisco.

The situation has become so bad that Sea World has suspended its sea lion show to help with rescuing the pups.

The theme park has treated 400 pups, more than double the number it would care for in a typical year, and built two temporary pools to look after them.