Records of Sika Deer Cervus nippon from the Southern Kuril Islands in 1986–2019, with Special Reference to a Continuous Record of Living Deer on Kunashir Island Since 2017

The sika deer (Cervus nippon) is native to eastern Asia and commonly occurs on Hokkaido Island, northern Japan. The nearby localities of the southern Kuril Islands, located east of Hokkaido, have not been regarded as part of the sika deer's regular range, despite isolated observations and trace evidence described before 2017. Here we consolidate the information of the sika deer in the southern Kuril Islands since 1986 with new information that establishes a continuous record of living sika deer on Kunashir Island from 2017 to 2019.