Roost and Echolocation Call Structure of the Alashanian PipistrelleHypsugo alaschanicus: First Confirmation as a Resident Species in Japan

Abstract

The Alashanian pipistrelle Hypsugo alaschanicus is a small Vespertilionid bat distributed in Mongolia, China, the Russian Far East, the Korean Peninsula and Japan (Horacek et al. 2000). The Japanese population of this species was formerly treated as Pipistrellus savii (Imaizumi 1960; Corbet 1978; Maeda 2005), which is distributed from south Europe to south Asia (Simmons 2005: treated as Hypsugo savii), although Yoshiyuki (1989) identified it as two species, P. coreensis (individuals from Tsushima Island) and P. savii velox (individuals from Hokkaido and Aomori). Only eight individuals of this species have been recorded in Japan to date: two from Tsushima Island (Yoshiyuki 1989), two from Aomori Prefecture (Yoshiyuki and Kimura 1975; Mukohyama 1996) and four from Sapporo (Imaizumi 1955; Hattori 1966; Abe 2007; Kondo et al. 2011). There are two opinions about the distributional status of this species in Japan. One is that the species is resident throughout the year and reproducing in Japan (Yoshiyuki and Kimura 1975). The other is that the species is a vagrant from the continent (Maeda 2005). Because there are few records and no information about ecological or behavioral characteristics, such as feeding habitat and echolocation call structure, throughout its known distribution in Japan, this species is listed as ‘Data Deficient’ in the Japanese Red List (Ministry of the Environment: http://www.biodic.go.jp/rdb/rdb_f.html). On September 2010, one bat resembling H. alaschanicus, was collected from an old building in Otaru, Hokkaido and another was discovered in the collection of a local museum. In addition, small bats have frequently been observed flying and resting around the building (M. Mochida, unpublished data). In this report we aim to (1) confirm the species of the two specimens based on their external and cranial characteristics, (2) describe a day roost at the site where the bat was collected, and (3) describe the echolocation call structure of this species.