225.

Gray Long-eared Bat

Plecotus austriacus

French: Oreillard gris / German: Graues Langohr / Spanish: Orejudo gris

Other common names: Gray Big-eared Bat

Taxonomy. Vespertilio austriacus J. B. Fischer, 1829,

Vienna, Austria.

This species is monotypic.

Distribution. S Britain, W France, and Iberian Peninsula E through C Europe and extreme S Sweden to W Ukraine and Balkans; also major W Mediterranean Is (Balearic, Corsica, Sardinia, Sicily, and Malta) and Madeira I.

Descriptive notes. Head-body 41-58 mm, tail 37-55 mm, ear 31-41 mm, forearm 36-5—43- 5 mm; weight 6-10 g. The Gray Long-eared Bat differs from the Brown Longeared Bat ( P. auritus) by its long dark muzzle with dark face. Dorsal furis dark gray or gray, with brownish hue; ventral fur is whitish or frosted. Also distinctive forits dark, broad (over 5- 5 mm) and long (over 14 mm) tragus, short thumbs (less than 6- 5 mm), and club-shaped penis, broader at terminal part. Dental formulais12/3,C1/1,P 2/3, M 3/3 (x2) = 36.

Habitat. Occurs up to 1390 m, from lowland valleys and grasslands to high mountain pastures or woodlands. In Central Europe,it is found in warm habitats such as lowlands, mostly around human settlements and agricultural land; tends to be closely associated with open landscape. In southern Europe,it is much more adaptable, inhabiting a broader variety of habitats.

Food and Feeding. Feeds mostly on Lepidoptera (Geometridae), which were present in 70-100% of examined fecal pellets. Depending on the season and on insect availability, beetles, common crane flies, and other Diptera are also consumed. It seems to use aerial-hawking more often than gleaning; hunts insects at heights of 2-5 m, but has been reported to hunt above the canopy, at ¢. 10 m.

Breeding. Maternity colonies are usually formed by groups ofa few tens of individuals (rarely 100), typically found in anthropic structures such as houses, in roofs, cavities, fissures, castles, churches, and bat boxes, but often in natural roosts in hollow trees or underground sites such as caves or mines. Nursery colonies are usually found at lower elevations than other roosts, normally below 550 m. Births take place at the end of June, and reports of mating activity can be found in May—November.

Activity patterns. In north, roosts in roofs of cathedrals, cellars, churches, and other old buildings. In south, much more flexible, also roosting in rock crevices, entrances of caves, and fissures in cliffs or bridges; bat boxes are only occasionally used. It has the typical echolocation of long-eared bats with calls that have two FM harmonics. Frequency varies substantially, dropping from 40 kHz to 20 kHz in the first harmonic and from 70 kHz to 40 kHz in the second. In general, echolocation is of weak intensity and for this reason, the species is difficult to monitor by acoustic surveys.

Movements, Home range and Social organization. Commutes up to 12 km to foraging areas by night, although it usually only flies c. 5 km and has very restricted foraging areas. In winter, it moves to hibernation sites, usually in small groups orclusters, or even individually, in caves or mines; such movements tend to be very short, with maximum recorded distance of ¢. 62 km.

Status and Conservation. Classified as Least Concern on The IUCN Red List. Widespread and generally common, especially in Mediterranean region, but locally rare in Eastern Europe. Population declines have been reported in Austria and Croatia. Threats include roost disturbance and loss, and habitat fragmentation due to agricultural intensification, but at present there is no evidence of a marked general decline.

Bibliography. Bogdanowicz (1999b), Dietz & Kiefer (2016), Horaéek et al. (2004), Hutterer et al. (2005), Juste, Ibanez et al. (2004), Juste, Karatas et al. (2008), Koopman (1993), Sokolov & Orlov (1980), Spitzenberger (2002, 2005), Spitzenberger et al. (2006), Stubbe & Chotolchu (1968), Tvrtkovi¢ (2006).