A surfer's day on the waves quickly turned into a fight for his board -- 'cause a sea otter stole it from him as he was dippin' in the Pacific Ocean, and refused to give it back!!
The wild scene all happened off the shores of California on Monday when an otter plopped itself onto Nick Ericksen's ride as he was hittin' the waves.
Video shot by one of Ericksen's friends showed despite all of the surfer's efforts to displace the animal -- it wasn't budging.
The two then engaged in a standoff for several moments -- with the otter in absolutely no mood to get back in the water.