Atypical interactions between male southern sea otters and pinnipeds

Here we describe unusual interspecific interactions between two male southern sea otters (Enhydra lutris neries) and pinnipeds. These two sea otters were among 30 male and 110 female otters translocated from central California to San Nicolas Island (SNI, 33”15’N, 119”3O’W), one of the California Channel Islands. Each otter was uniquely marked with two plastic colored tags before release. Prior to our observations each focal animal had lost one of its tags which precluded identification. On one of the otters, referred to as BB, there was a distinctive slit in the interdigital webbing which, in addition to the remaining chartreuse tag, allowed us to be certain observations were of the same individual. On the other otter, referred to as PKY, the single remaining white tag had been chewed in half in a distinctive fashion. In addition, PKY was observed in an area with no other sea otters.