Distribution and extinction of the Eurasian otter Lutra lutra on the Goto Islands, Nagasaki Prefecture, Japan

Abstract

To elucidate the past distribution of an extinct local population of the Eurasian otter (Lutra lutra), we conducted a literature review and interview survey on the Goto Islands, Nagasaki Prefecture, western Japan. We found nine records in public libraries, and eight witnesses among local elderly persons. The evidence strongly suggest that otters once lived in this area. The latest literal record of the otter was in the 1950s, whereas the latest eyewitness was in 1981. The result implies that the extinction of the otter population from Goto Islands was largely due to overhunting and poaching after the ban in 1928, while habitat loss seemed to act as an additional factor. We expect that further studies can reveal physical evidence of the otter (e.g. photos and furs) as well as accumulating its records in this area.