219.

Western Barbastelle

Barbastella barbastellus

French: Barbastelle d'Europe / German: Mopsfledermaus / Spanish: Barbastela

Other comesnon names: Barbastelle

Taxonomy. Vespertilio barbastellus Schreber, 1774,

Burgundy, France.

Two subspecies are recognized.

Subspecies and Distribution. B.b.barbastellusSchreber,1774—EuropefromIrelandandIberianPeninsulaEtoLaivia,Belarus,Ukraine,andtheCauca-sus;alsomajorMediterraneanIs,Moroc-co,andTurkey(Anatolia);possiblyextinctinBelgium,Netherlands,andNorway.

B. b. guanchae Trujillo, Ibanez & Juste, 2002 — Canary Is (Tenerife and La Gomera).

Descriptive notes. Head-body 45-60 mm, tail 36-52 mm, ear 12-18 mm, forearm 35-43 mm; weight 5-14 g. Females slightly larger than males; body slender. Fur is long, silky, and black-brown, frosted with white or yellowish-golden tips. Skin dark brown or grey. Juvenile much darker than adult. Ears have distinctive flap of skin (c.5-6 transverse folds) on outer edge; tragus triangular and very distinctive, tapering very abruptly to end with relatively rounded tip; ears never folded when resting. In contrast to Plecotus, eyes remarkably small. Wings blackish, relatively long and narrow; uropatagium attached to base of toes; fur covers part of both uropatagium and wings; calcar is one-half length of uropatagium and has protuberant distal postcalcarial lobe. Tail is almost same length as body. Can be confused with the Eastern Barbastelle ( B. darjelingensis) and the Arabian Barbastelle ( B. leucomelas), but easily separated by its short, wide trapezium-shaped ears that face forward and join over top of head, and its short snout. Baculum 0-76- 0-85 mm long, with broad section in proximal part and narrow section in distal area. Skull light and delicate, with long, rounded braincase but short rostrum, characterized by flattened area extending to not greatly developed supraorbital ridge; bullae are not very large compared to similar species. Condylo-basal length 12:4-14- 1 mm; zygomatic width 7-8- 2 mm; interorbital width 3:4- 3-9 mm; length of maxillary tooth rows 4- 3-5 mm; and lengths of mandible 8-4-9- 5 mm. Dental formula for all species of Barbastellais 12/3, C 1/1, P 2/2, M 3/3 (x2) = 34. Chromosomal complement has 2n = 32 and FN = 50.

Habitat. Associated with old mature forest (linked to presence of dead trees), commonly coniferous. Mostly forages in edge habitats (woodland edges), above water surfaces or in semi-open areas above tree canopy; also riparian forests and other deciduous woodlands. In north, it occurs in lowlands; in south, tends to be found in highlands. Commuting individuals are easily detected in all habitats, including urban areas, open spaces, grasslands or forest edges. In Italy, has been found breeding in rocks and foraging in apparently unsuitable areas such as open landscapes; but in Switzerland, seemsto select positively well-structured forests, generally mature woodlands, and avoid open woodlands and rocky slopes. Recorded from sea level up to 2260 m.

Food and Feeding. Feeds mainly on Lepidoptera, positively selecting large moths and tympanate moths; rest of diet consists of Diptera (e.g. Tipulidae and small Nematocera) in very low proportions, as well as Trichoptera, Neuroptera, Homoptera, and Hymenoptera; Coleoptera and spiders are even less frequent. In general, this species has a very narrow dietary niche breadth. In Germany, occurrence of moths in its diet has been quantified as 73-94% by weight; and in Swiss Alps as 99% by volume; in contrast,it is rare to find remains of dung beetles or other hard-bodied insects in the feces. Generally considered an aerial-hawker, only occasionally gleaning (e.g. spiders), probably depending on prey availability and usually no more than 5 m aboveground. However, both techniques have been reported and there is disagreement about the main foraging strategy. Bats foraging above the tree canopy have been reported to make quick dives into the forest.

Breeding. Maternity colonies can comprise up to 30 individuals (in tree roosts) and tend to be found in old woodlands, old houses, domestic dwellings, and hollow trees. During maternity period, the species roosts under the bark of oak, beech or spruce. Occasionally reported in colonies of up to 100 (especially in buildings); in smaller numbers in rock crevices. Especially during post-lactating period,it habitually changes roosts (except buildings) quite often, sometimes even daily or every few days. Females become sexually active after the first year of life and can give birth to a single young or twins in segregated colonies, separated from males and passive females. Young are born from May to August and become fully independent in 6-9 weeks. Mating occurs in swarming sites or caves during autumn, from September to November. Mating has rarely been reported during winter in parts of its distribution. It can live up to 23 years.

Activity patterns. Roosts under bark of old pines, but also occasionally in meadows, gardens, or hedges. Emerges early at night, before sunset, and sometimes even during daylight. In order to minimize predation risk, it forages in close, dark habitats early on, and only forages in open spaces at later stages of the night. Reported to fly low and at very low speed, it can also forage high up with fast flight. This species continuously shifts roost from tree to tree; as it tends to roost under bark of old branches (very ephemeral type of roost), it needs to look for new potential roosts every night; this behavior might be important for individual recruiting and territorial relationships. Hibernating bats tend to arise and emerge every c.15 days. Echolocation is one of the easiest European species to identify: it counts with alternate calls of two different types, concave and convex curves,at different frequencies and amplitudes; these differences are partially caused by head movements. The first call type lies at 30-37 kHz, the second at 30-43 kHz; the first type is always much louder. Minimum frequencies are at c.28-4 kHz, maximum frequencies ¢.46 kHz, and pulse durations 1-5 milliseconds. This type of echolocation with alternate calls at different frequencies allows the bat to hunt moths in flightas it avoids emitting calls at the moths’ hearing frequencies.

Movements, Home range and Social organization. Considered sedentary. Travels up to 20 km to reach its hunting grounds, with an average distance of ¢. 7 km. Non-breeding females tend to forage further than those lactating or post-lactating. Commuting paths are quite straight and fast, across open areas and meadows. In winter, the species shifts in small groups or individually from the maternity roosts to hibernation sites, which may be up to 40 km away; distances poorly known, but longest movement recorded was ¢. 290 km between Austria and Hungary. Hibernation might start on trees, but the species tends to select underground sites such as caves, where it can roost in small clusters or individually in crevices. However, colonies of over 1000 have been reported in France, and of over 7000 in Slovakia and Poland. When natural caves are scarce, the species congregates in higher numbers in bunkers or mines. Temperatures in hibernacula are mostly 2-5°C, and humidity tends to be very low. It can share hibernation roosts with other species such as Natterer’s Myotis ( Myotis nattereri), Greater Myotis ( M. myotis), Daubenton’s Myotis ( M. daubentonii), or other Myotis spp., although rarely clustering together.

Status and Conservation. Classified as Near Threatened on The IUCN Red List. The species is very rare and apparently declining almost throughoutits range, occurring in very low numbers, and highly vulnerable due to its sedentarism; it may be extinct in Belgium and Netherlands, and also in Norway, where it has not been recorded since 1949. Remaining populations are associated with old, mature woodlands. Recovery of populationsis a very slow process and dramatic declines have recently been reported in many regions. Only in Germany, where insecticide use was reduced, have populations seemed to recover. The main threat is habitat loss, which is directly linked to modern forestry practices. As a reference, one colony, that is known to shift from roost to roost during the same season, might use up to 30 holes in a relatively small patch of forest per summer. Unfortunately, secondary forests do not offer enough mature trees for this species. In addition, roost and cave disturbance by tourists and speleologists are major threats.

Bibliography. Ancillotto, Cistrone et al. (2015), Andreas et al. (2012), Benzal et al. (2001), Bogdanowicz (1983), Denzinger et al. (2001), Dietz & Kiefer (2016), Flaquer et al. (2004), Gottfried (2009), Hutterer et al. (2005), Juste et al. (2003), Lesinski et al. (2005), Nowak (1999), Obrist et al. (2004), Parsons & Jones (2000), Russo, Cistrone & Jones (2005), Russo, Cistrone, Jones & Mazzoleni (2004), Rydell & Bogdanowicz (1997), Rydell et al. (1996), Sachanowicz & Zub (2002), Sierro (1999), Stebbings & Griffith (1986), Trujillo et al. (2002), Zeale et al. (2012).