Western barbastelle

Barbastelle
Conservation status
Near Threatened  (IUCN 3.1)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Chiroptera
Family:	Vespertilionidae
Genus:	Barbastella
Species:	B. barbastellus
Binomial name
Barbastella barbastellus (Schreber, 1774)
Western barbastelle range

The western barbastelle (Barbastella barbastellus), also known as the barbastelle or barbastelle bat, is a European bat in the genus Barbastella. This species is found from Portugal to Azerbaijan and from Sweden to Canary Islands, where a sub-species was identified. It has a short nose, small eyes and wide ears. The conservation status of B. barbastellus is assessed as "Near Threatened", "Vulnerable", "Critically Endangered" or "Extinct" in various parts of its range.

Taxonomy

Barbastella barbastellus was named by Johann Christian Daniel von Schreber in 1774 from specimens collected in Burgundy, France (type locality). The name Barbastella barbastellus might be coming from the Latin barba (beard) and stella (star). Viewed from the side, it seems that the upper lip has a beard, or a moustache.

So far, two sub-species were identified :

• Barbastellus barbastellus barbastellus : distributed from western Europe until the Caucasus, with isolated populations in Morocco
• Barbastellus barbastellus guanchae : only found in the islands of Tenerife and La Gomera, Canary Islands, Spain

Description

The barbastelle has, like the rest of the animal kingdom of this world, participated in an evolutionary arms race. The foe for the bat order Chiroptera is its prey, the moth order Lepidoptera. To minimize the risk of the bats' echolocation, moths [and in rarest examples, butterflies] have evolved to detect the echolocation calls of hunting bats, and evoke evasive flight manoeuvres, or reply with their own ultrasonic clicks to confuse the bat's echolocation. The Arctiidae subfamily of Noctuid moths uniquely respond to bat echolocation in three prevailing hypotheses: startle, sonar jamming, and acoustic aposematic defence. All these differences depend on specific environmental settings and the type of echolocation call; however, these hypotheses are not mutually exclusive and can be used by the same moth for defence.

In response, to continue the race, some bat families are known to use clicks at frequencies above or below moths' hearing ranges. This is known as the allotonic frequency hypothesis. It argues that the auditory systems in moths have driven their bat predators to use higher or lower frequency echolocation to circumvent the moth hearing. Barbastelle bats have evolved to use a quieter mode of echolocation, calling at a reduced volume and further reducing the volume of their clicks as they close in on prey moths. The lower volume of clicks reduces the effective successful hunting range, but results in a significantly higher number of moths caught than other, louder bat species. Moths have further evolved the ability to discriminate between high and low echolocation click rates, which indicates whether the bat has just detected their presence or is actively pursuing them. This allows them to decide whether or not defensive ultrasonic clicks are worth the time and energy expenditure.

Ecology

Habitat

Barbastelles roost in splits or behind loose bark of trees all year, normally in mature deciduous forests, as well as within human buildings. While barbastelles typically remain within a single roosting area, they move between individual roosts with great frequency.

Barbastelles migrate to underground roosting sites over the winter, although they may within arboreal roosts in the beginning of the season. Winter roosting sites include natural caves and human structures such as basements, mines and bunkers. Barbastelles are relatively resistant to cold conditions, and are typically found hibernating in cold sites and in exposed positions.

Hunting and feeding

Barbastelles feed chiefly on moths, as well as on flies and beetles.

Echolocation

The barbastelle has two main call types used for echolocation. The frequency parameters of call type 1 lie between 30–38 kHz, have most energy at 33 kHz and have an average duration of 2.5 ms. The frequency parameters of call type 2 lie between 29–47 kHz, have most energy at 38 kHz and have an average duration of 4.1 ms. 30–38 kHz, have most energy at 33 kHz and have an average duration of 2.5 ms. The frequency parameters of call type 2 lie between 29–47 kHz, have most energy at 38 kHz and have an average duration of 4.1 ms.

Distribution

It is rare and decreasing throughout its range.

Albania

So far, only four specimens of this species were recorded in Albania. The specimens were caught in 2005 near the Shebenik-Jabllanicë National Park, close to the border with Northern Macedonia. This national park is well known for its beech forest, part of the UNESCO site "Ancient and Primeval Beech Forests of the Carpathians and Other Regions of Europe".

Belgium

Barbastelle bats are known to occur within the Sonian Forest of Belgium.

Ireland

This species was reported in 1997 from the west coast of Ireland, based on echolocation calls. Recent surveys and researches assessed this data and concluded to a mis-identification of the echolocation calls, and the absence of this species from the island of Ireland.

Montenegro

The species is present during summer in both Mediterranean and Alpine biogeographic region of Montenegro, on altitudes as low as 80 m and up to 1.700 m a.s.l.

Netherlands

The barbastelle has been extinct in the Netherlands since 1984.

Norway

It was considered extirpated in Norway, having only been sighted in 1896, 1911, 1913 and 1949. However, it was again found in 2004 and 2008.

United Kindgom

In Britain, only a few breeding roosts are known; Paston Great Barn in Norfolk, parts of Exmoor and the Quantock Hills in Devon and Somerset (see Tarr Steps), Wimpole Wood in Cambridgeshire, the Mottisfont woodland in Hampshire and Ebernoe Common in West Sussex. The UK distribution can be found on the National Biodiversity Network website here.

Conservation

This species is protected in the European Union under the Habitats Directive, meaning that habitats and roosts use by this species may be considered for notification as a Site of Special Scientific Interest. This species is also listed in the Berne Convention and is specifically targeted by the UNEP-EUROBATS convention. Several national legislation are also protecting this species and its habitats in many countries and regions.

In order to highlight the importance of protecting this species at the European scale, this species was selected as bat species of the Year 2020-2021 by the pan-European NGO BatLife Europe.

Literature cited

• Buckley, D. J., Puechmaille, S. J., Roche, N., & Teeling, E. C. 2011. A critical assessment of the presence of Barbastella barbastellus and Nyctalus noctula in Ireland with a description of N. leisleri echolocation calls from Ireland. Hystrix, the Italian Journal of Mammalogy, 22(1).
• Obrist, M.K., Boesch, R., Flückiger, P.F. 2004 Variability in echolocation call design of 26 Swiss bat species: Consequences, limits and options for automated field identification with a synergetic pattern recognition approach. Mammalia. 68 (4): 307–322
• Parsons, S. & Jones, G. 2000. Acoustic identification of twelve species of echolocating bat by discriminant function analysis and artificial neural networks. The Journal of Experimental Biology. 203(17)2641–2656. PMID 10934005
• Pašić, J. & Mulaomerović, J. 2018. Barbastella barbastellus – new sites, 2017 – 2018, Montenegro Barbastella barbastellus – novi lokaliteti, 2017. – 2018. Crna gora. Hypsugo Journal. III(2):37-40.
• Rachwald, A., Kokurewicz, T., Zapart, A., Apoznański, G., Szurlej, M., Haddow, J., Đurović, M. & Kepel, A. 2019. New Records of the Western Barbastelle Barbastella barbastellus (Schreber, 1774) and Other Rare Bat Species in Montenegro. Acta Zoologica Bulgarica. 71 (4):519-524
• Rydell, J., & Bogdanowicz, W. 1997. Barbastella barbastellus. Mammalian Species, (557), 1-8.
• Sachanowicz, K., Ciechanowski, M., Rachwald, A., & Piskorski, M. 2016. Overview of bat species reported in Albania with the first country records for eight species. Journal of natural history, 50(7-8), 513-521
• Théou, P. & Bego, F. 2018. Bats of Albania. NaturAl Project. 124pp
• Trujillo, D., Ibáñez, C., & Juste, J. 2002. A new subspecies of Barbastella barbastellus (Mammalia: Chiroptera: Vespertilionidae) from the Canary Islands. Revue suisse de zoologie; annales de la Société zoologique suisse et du Muséum d'histoire naturelle de Genève. 109(3):543-550.
• Yager, D. 2012. Predator detection and evasion by flying insects. Current Opinion in Neurobiology. 22(2) 203 (Pt 17): 201–207. PMID 22226428.

External links

• ARKive page about barbastelles
• Woodland Management For Bats Guide
• Barbastella barbastellus - Science for Nature Foundation
• www.worlddeer.org/britishbats/barbastelle
• IUCN
• Western Barbastelle Bat (Science For Nature Foundation)