Researchers have found an answer to a grim, whodunit-style mystery where the headless bodies of harbor seal pups were found on Northern California beaches from Santa Cruz to Mendocino.
The answer, caught on hidden motion sensor cameras, not only ended the mystery but also showed nature taking its course: coyotes eating those seal pups.
The cameras are part of UC Santa Cruz PhD student Frankie Gerraty’s research on the connection between land and sea.
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“One of the most interesting findings from our recent research has been that coyotes are not only scavenging mammal carcasses, but they are also, on occasion, killing seal pups as well,” Gerraty said.
From Ano Nuevo State Beach to the Mendocino County Coastline, coyotes have killed dozens of harbor seal pups — and, in many cases, bitten off their heads.
While those coyotes don’t appear to be attacking giant elephant seals, there is evidence that they are now going after the fins of elephant seal pups.
Research scientist Rachel Reid, who studies the eating habits of coyotes along the California coast, said seals currently make up 20% of their diet.
“I think coyotes have been using the beach for quite some time,” Reid said. “The reason it’s attractive is that there are food resources that are very high-quality. A marine mammal has a huge fat content.”
More coyotes heading to the beach for dinner could mean a bigger impact on marine life in the future, according to scientists.
“I think the main challenge for the seals will be that if this becomes a bigger issue, if they start losing a lot of their pups to predation, that they might need to choose different places to have their babies,” Reid said.
