Hundreds of Emaciated Stranded Sea Lion Pups Are Washing Ashore in California

Since January, hundreds of emaciated, weak sea lion pups have washed up on the shores of Southern California, Wired reports. And as the months passed, there have more, rather than fewer, of them. Scientists say the number of stranded pups are alarming and abnormal, but they have no idea what is behind the worrisome trend.

So far, Wired writes, a handful of rescue centers between San Diego and Santa Barbara have admitted 517 pups. Most of the pups are around nine months old. They weigh just half of what healthy pups should, and they show signs of hypothermia and dehydration in addition to malnourishment. Some scientists suspect the pups are leaving home early, but why they would chose to do so remains a mystery.

While hundreds of the pups will spend several months in rehab before hopefully being returned to sea in healthy condition, others are not so lucky. Many had to be humanely euthanized since they were beyond help.

Nesting pelicans, too, seem to be doing poorer than usual. Researchers suspect that there may be something amiss with the prey species such as sardines and anchovies that both sea lions and pelicans feed on, though further investigations are needed before they can definitively make this link.

In the meantime, shelters are struggling just to keep up with the number of pups admitted in need of immediate help, and those numbers seem only to be accelerating.

More from Smithsonian.com:

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Rachel Nuwer | | READ MORE

Rachel Nuwer is a freelance science writer based in Brooklyn.