Abstract
Little is known about roosting habitat of tree-roosting bats in Japan. We used radiotransmitters to locate and characterize day-roosts of parturient Ikonnikov's whiskered bats, Myotis ikonnikovi. One pregnant female bat was radiotracked in a temperate deciduous forest in Nikko, Tochigi prefecture, Japan during July 2004. We followed the bat for 3 days and found 2 roosts located under the exfoliating bark of snags. A large number of bats emerged for 3 days continuously from one of the snags. We counted up to 31 bats emerging from the roost, which was the largest aggregation ever reported in natural roosts of the species.
