A sea otter is the unexpected perpetrator of a string of surfboard thefts along a section of a Californian coastline.
The otter has gotten onto surfboards in at least four different instances, nipping and scratching them.
In some of these incidents, the mammal's aggressive behavior forced surfers to put down their surfing boards and swim back to the safe shore.
Signs announcing the presence of an "aggressive sea otter in this area" have since been placed along the Santa Cruz shoreline by the US Fish and Wildlife Service.
"Enter the water at your own risk," the cautions reads.
Photographer Mark Woodward, also known as Native Santa Cruz on Twitter and Instagram, has been posting pictures and videos of sea otters grabbing boards and riding them.
"This may seem cute and funny, but it's getting to be dangerous," he wrote in an Instagram post.
"I'm afraid that the sea otter, which was born in captivity and released when it was old enough, will have to be captured and live at a rescue sanctuary."
The otter, named 841, was born five years ago to an otter that was also well-known for approaching kayakers.
However, because 841 was raised in captivity, it is unlikely that it mimicked its mother's actions.
According to the Fish and Wildlife Service, experts don't have a clear reason for the behavior, although they suggested the otter may be experiencing hormone surges or is being fed by people.
Wildlife officials are collaborating with Monterey Bay Aquarium sea otter specialists in an effort to capture and relocate the animal.