Five day-roosts of Myotis yanbarensis and Murina ryukyuana on the Amami-Oshima Island, Kagoshima, Japan

Abstract

We found three day-roosts of Myotis yanbarensis and two day-roosts of Murina ryukyuana on the Amami-Oshima Island from 2016 to 2019. The day-roosts of Myotis yanbarensis were found inside forest culverts in a drainage hole and a crack in the ceiling. We also found two bats using a tree cavity in winter, revealing that this species uses both artificial structures and tree cavities as day-roosts. Solitary Murina ryukyuana individuals were found inside a dead leaf, 2.2 m above the ground, and inside a dead tree in the forest. Our results demonstrate that both species use tree cavities or snags, and therefore, cavity-forming trees and snags are likely important for the conservation of these bats. However, further research is needed as roost records are still sparse.