Estonian Journal of Ecology, 2010, 59, 1, 6269 doi: 10.3176/eco.2010.1.05 62 New data on the distribution of the barbastelle bat Barbastella barbastellus in Latvia Gunārs Pētersons a ! , Viesturs Vintulis b , and Jurģis uba b a Faculty of Veterinary Medicine, Latvia University of Agriculture, Kr. Helmana 4, LV3004 Jelgava, Latvia b Faculty of Biology, University of Latvia, A. Kronvalda blvd. 4, LV1842 Rīga, Latvia ! Corresponding author, gunars.petersons@llu.lv Received 17 December 2008, revised 9 June 2009 Abstract. The barbastelle bat Barbastella barbastellus is considered as a rare species with an unclear status of distribution. Only a few occasional winter records, single records, and a few observations during the autumn migration at the SW coast of Latvia have been reported in the literature. A survey on the distribution of the barbastelle bat was conducted in Latvia in 2006 and 2007. Ultrasound detectors with the time expansion sound transformation method, capture with mist nets, and inspection of cellars were used to find barbastelles. In total 20 new sites occupied by barbastelles were found in the central and northern parts of Latvia. Key words: Barbastella barbastellus, distribution, Latvia, ultrasound, survey. INTRODUCTION The barbastelle bat Barbastella barbastellus (Schreber, 1774) is regarded as one of the most endangered bat species in Europe. It is included in the Annexes II and IV of the Habitat Directive. The threats to populations of barbastelles are largely unknown. However, due to some specific features of this species, particularly feeding almost exclusively on moths and common use of crevices behind the bark of old or dead deciduous trees, barbastelles are probably especially vulnerable against intensive forest management practices (Rydell et al., 1996; Sierro & Arlettaz, 1997; Russo et al., 2004). The barbastelle bat can be found throughout Europe (Rydell & Bogdanowicz, 1997). In the northern and north-eastern parts of Europe it has been recorded in South Norway (Gjerde, 2008), South Sweden (AhlØn & Gerell, 1989), the western part of Belarus (Kurskov, 1981; Demjanchik & Demjanchik, 2000), South Lithuania (Masing & Busha, 1983; Pauza & Pauziene, 1998; Baranauskas, 2001), and also in Latvia (Bua, 1986; Pētersons & Vintulis, 1998). In Lithuania D. Paua and his colleagues summarized all data of records on barbastelles and suggested that the northern border of the species range lies in the central part of the country (Pauza et al., 2003). There are no published data on the occurrence of barbastelles in Estonia.