Dai Fukui

Acoustic Identification of Eight Species of Bat (Mammalia: Chiroptera) Inhabiting Forests of Southern Hokkaido, Japan: Potential for Conservation Monitoring

Abstract Assessing the impact of forest management on bat communities requires a reliable method for measuring patterns of habitat use by individual species. A measure of activity can be obtained by monitoring echolocation calls, but identification of species is not always straightforward. We assess the feasibility of using analysis of time-expanded echolocation calls to identify free-flying bats in the Tomakomai Experimental Forest of Hokkaido University, Hokkaido, northern Japan. Echolocation calls of eight bat species were recorded in one or more of three conditions: from hand-released individuals, from bats flying in a confined space and from bats emerging from their roost. Sonograms of 171 calls from 8 bat species were analyzed. These calls could be categorized into 3 types according to their structure: FM/CF/FM type (Rhinolophus ferrumequinum), FM types (Murina leucogaster, Murina ussuriensis, Myotis macrodactylus and Myotis ikonnikovi) and FM/QCF types (Eptesicus nilssonii, Vespertilio superans and Nyctalus aviator). Sonograms of the calls of R. ferrumequinum could easily be distinguished from those of all other species by eye. For the remaining calls, seven parameters (measures of frequency, duration and inter-call interval) were examined using discriminant function analysis, and 92% of calls were correctly classified to species. For each species, at least 80% of calls were correctly classified. We conclude that analysis of echolocation calls is a viable method for distinguishing between species of bats in the Tomakomai Experimental Forest, and that this approach could be applied to examine species differences in patterns of habitat-use within the forest.

Maternity Roosts and Behaviour of the Ussurian Tube-Nosed Bat Murina ussuriensis

The genus Murina has a wide geographic distribution and includes about 35 species, but very little information is available on the maternity behaviour of any of them. We conducted a preliminary study of a maternity colony of Murina ussuriensis in warm temperate rain forest of Yakushima, Japan. Day roosts of six nursing females were located by radio-telemetry. During the eight days of the study 18 maternity roost locations were confirmed. The nine roosts that were clearly visible included four types: vertically suspended clusters of dead leaves, tree hollows, a crevice in a root plate and a completely exposed site under a branch. Whenever the same female was located on successive days, she had switched from her previous roost, and none of the roosts was re-used by a radio-tagged female during the study period. The number of individuals recorded roosting together ranged from two (a mother with infant) to 22 individuals. The first emergence of an adult female occurred between 13 and 47 minutes after sunset. Mothers returned to the roost about 30 minutes after their first emergence, repeatedly hovering near the roost, landing and departing again. Some offspring left the roost independently, while non-volant offspring were carried away by an adult, presumably the mother. Various types of social calls were recorded, beginning when the first mother returned to the roost, and then almost continuously until the last individual left the roost. These preliminary results suggest that maternity colonies show very frequent roost-switching, may exhibit fission-fusion behaviour and have an extensive vocal repertoire.

The Effect of Roost Environment on Roost Selection by Non-Reproductive and Dispersing Asian Parti-Coloured Bats Vespertilio sinensis

Abstract. Roosting of Asian parti-coloured bats (Vespertilio sinensis) in man-made structures is frequently results in conflict with humans. Therefore, to determine optimal alternative roosts, we studied roost preference of this species by testing the effects of roost temperature, surrounding environment and the distance from the nearest nursery colony on roost selection by V. sinensis in manipulative field experiments. We installed white (cooler) and black (warmer) bat boxes at shaded and sun-exposed sites. Although no nursery colonies were formed in the bat boxes, a few individuals (1–5) roosted during the lactation period, while many individuals (≥20) roosted during the post-lactation period. During lactation, bats used both white and black boxes, but preferred using the boxes placed at the shaded sites over those placed at the sun-exposed sites. On the other hand, during the post-lactation period, almost all individuals used the white boxes rather than the black boxes. However, adult females preferred the shaded sites while young females preferred the sun-exposed sites. In conclusion, V. sinensis exhibited seasonal changes in roost selection, implying that several types of bat boxes in different environments need to be installed as alternative roosts. In the future, other types of bat boxes should be tested as alternative nursery roosts.

Seasonal change in the diet composition of the Asian parti-coloured bat Vespertilio sinensis

Abstract. We determined the food habit of the Asian parti-coloured bat Vespertilio sinensis from May to August by analysing their faecal samples. Eight orders of insects were identified in the faeces. Lepidoptera, Diptera and Coleoptera had high frequencies of occurrence, but the proportion of each order varied with the sampling period. A comparison between diet composition and relative insect abundance showed that proportions of Coleoptera in the diet were larger than those in insect abundance. This pattern also was true for Lepidoptera in some sampling periods. In contrast, proportions of Diptera in the diet were lower than those in insect abundance, although Diptera was a major prey item. These results suggest that the diet composition of V. sinensis may be biased towards larger-sized taxa. Furthermore, the lack of any significant differences between diet composition and insect abundance for the other five orders suggested that the diet composition of V. sinensis is also influenced by the seasonal prevalence of each insect taxon.

Geographical variation in the cranial and external characters of the little tube-nosed bat, Murina silvatica in the Japanese archipelago

The distribution ofMurina silvatica (Yoshiyuki, 1983) in the Japanese archipelago extends over about 2000 km from north to south. Specimens were obtained from populations in Hokkaido and Yakushima, which are at the northern and southern ends of the range, and from two intermediate locations in Honshu. Measurements of cranial and external morphology were examined for evidence of geographical variation. The results of both multivariate analysis of variance and cluster analysis showed that there was no distinct cline in skull morphology among the Hokkaido, Tohoku and Chubu populations. However, the results of multivariate analysis of variance showed that all measures were significantly greater for the Yakushima population than for the others. Similarly, in a dendrogram of cluster analysis, the Yakushima population formed a cluster that was distinct from the other populations. However, as the difference between the Yakushima population and the other populations was less than the variation found within the Hokkaido, Tohoku and Chubu populations, morphological divergence of the Yakushima population was attributable to intraspecific variation. The island of Yakushima is the most isolated of the four locations and the morphological divergence of this population may be associated with its relative geographic isolation.

Vespertilio murinus Linnaeus, 1758 Confirmed in Japan from Morphology and Mitochondrial DNA

In December 2005, three bats of indeterminate identity were captured in northern Japan. Their forearm lengths were slightly smaller than the average for Vespertilio sinensis. We identified these three individuals as V. murinus using both morphological and molecular approaches, and discussed their possible migration or vagrancy routes. Prior to the first record of V. murinus on Rebun Island near Hokkaido in 2002, there was no record of this species in Japan. These new occurrences illustrate the importance of determining possible migration or vagrancy routes of bats for understanding and preventing the spread of zoonotic diseases.

First Records of Myotis altarium (Chiroptera: Vespertilionidae) from India and Vietnam

Abstract. The Szechwan myotis, Myotis altarium, was first described in 1911 from southeastern China, and for the next 100 years was thought to be restricted to that country with just one additional individual known from Aung Kang region in northern Thailand. We captured eight individuals of this species during surveys in Copia Nature Reserve in northwestern Vietnam and two individuals from East Khasi Hills and East Jaintia Hills districts of Meghalaya state, northeastern India. They are described here as the first records for Vietnam and India. We also provide comparative mensural data including the holotype and other specimens from Southeast Asia. The record of M. altarium from Meghalaya significantly extends the westward distribution range of this species beyond Thailand. Our study affirms previous observations of the cave dwelling habits of M. altarium and suggests that this species temporarily hibernates during cold winter periods in Vietnam. It is also suggested that its distribution range may encompass other karstic habitats in the mainland Indomalayan region.

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

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.

Influence of Trap Environment on the Effectiveness of an Acoustic Lure for Capturing Vespertilionid Bats in two Temperate Forest Zones in Japan

Abstract. Bats that typically forage in the forest understorey can be difficult to capture using mist nets or harp traps alone. We assessed the effectiveness of an ultrasonic lure for increasing capture rates of vespertilionid bats in two forest zones in Japan. One sequence of stimuli was modelled on social calls of four species that typically forage in narrow-space; the other on those of four species that forage along edges and in forest gaps. The lure increased capture rates by 24.5 times in cool temperate deciduous forest in Hokkaido, and 9.75 times in warm temperate evergreen rain forest in Yakushima, compared with the control condition. Narrow-space foraging bats of the genus Murina dominated the catch at both sites and were caught most frequently when the trap was located in the cluttered environment of the forest understorey. There was no significant effect of call type on capture rate. The lure is an effective method for increasing capture rates of bats and particularly for narrow-space foraging species within the forest, which are otherwise difficult to catch. Acoustic lures have great potential for enhancing study and survey capabilities for forest bats.

Ecology and Monogamous System of the Painted Woolly Bat Kerivoula picta in Khon Kaen, Thailand

Abstract. Day-roost usage, nocturnal activity, foraging area, and social structure of the painted wooly bat, Kerivoula picta, were investigated at the village of Khon Kaen in northwest part of Thailand. The bats mainly preferred dead banana leaves as day-roosts, while leaves of sugar cane or broad-leaved trees were occasionally used. They frequently switched their day-roosts every one to four days. Families numbering three bats (adult female, adult male, and young) were found in February, June, September and October. However, such families were not found in November and December when pairs constituted 64% of the total number of captured bats. Most of the pairs roosted together in day-roosts, and did not change their partners during the survey period each year. Foraging areas between contiguous pairs did not overlap each other. Foraging areas averaged 6.1 ha for males and 5.6 ha for females. Kerivoula picta fed chiefly on relatively small-sized web-building spiders. Most of the pairs changed partner every year. The recapture rates of newly banded bats after one year averaged 20%, and the oldest ages recorded were five years for females and four years for males.