Someone is killing California's protected sea otters

Rehabilitated sea otter Walter, right, who was blinded after a shotgun blast to the face near Tofino, British Columbia, Canada, swims with female Tanu after being introduced to her for the first time at the Vancouver Aquarium in Vancouver, British Columbia, Canada on Thursday, Nov. 6, 2014. (AP Photo/The Canadian Press, Darryl Dyck)

Before being hunted to near extinction for their pelts in the 18th and 19th centuries, sea otters littered the Pacific coast. Today the biggest threats to the 3,000 that remain are oil spills and tankers, reports the Guardian, and now a shooter on the loose near Santa Cruz, Calif.

Authorities have found in just a matter of days four male sea otters washed ashore, though the fourth body was so deteriorated it's not yet been determined whether it was also shot, reports the San Francisco Chronicle.

The endangered furry marine mammals are protected by the Marine Mammal Protection Act, California state law, and the Endangered Species Act, and the killer could face fines up to $100,000 and jail time.

"Finding several gunshot sea otters at the same general location during such a short time frame is very unusual," says a Fish and Wildlife Service rep.

"They’re a keystone species.... With the loss of these sea otters, we also have the loss of their benefit to the ecosystem." Almost exactly three years ago, three sea otters were found dead near Asilomar state beach in Pacific Grove, Calif., in what the FWS rep says is now considered a "cold case." The recently found otter carcasses are undergoing necropsies at a FWS lab in Oregon.

(One famous sea otter who survived an oil spill was ultimately nabbed by another ocean dweller.)

This article originally appeared on Newser: Someone Is Killing California's Protected Sea Otters

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