Nine sewellel (Aplodontia rufa) bone specimens are identified in the Duncan's Point Cave vertebrate archaeofauna. At least 3 individuals are represented and 3 specimens exhibit evidence of deposition in the cave as carnivore prey. The extralimital presence of A. rufa near the mouth of the Russian River demonstrates their occurrence over a wider area during the mid-Holocene and raises the possibility of the existence or recent extirpation of a 3rd isolated coastal Californian population of the species. Based on the presence of bones of A. rufa in the Duncan's Point Cave archaeofauna and the availability of suitable habitat in the region, a detailed survey of the area surrounding the mouth of the Russian River is warranted.