Whiskered bat (Myotis mystacinus)

French: Murin À Moustaches
Spanish: Murciélago Ratonero Bigotudo
GenusMyotis (1)
SizeHead-body length: 35 - 48 mm (2)
Forearm length: 32 - 36 mm (2)
Tail length: 30 - 43 mm (2)
Wingspan: 190 - 225 mm (2)
Ear: 12 - 17 mm (2)
Weight4 - 8 g (2)

The whiskered bat is classified as Least Concern (LC) on the IUCN Red List (8). In Great Britain, all bats are fully protected under Schedule 5 of the Wildlife and Countryside Act (1981) as amended, and by the Conservation (Natural Habitats etc) Regulations (1994) (3). An agreement on the Conservation of Bats in Europe (EUROBATS) under the auspices of the Bonn Convention, also known as the Convention on Migratory Species (CMS) is in force, and all European bats are listed under Appendix II of the CMS (4).

The whiskered bat (Myotis mystacinus) is the smallest member of the Myotis genus in Europe (2). It is very similar in appearance to Brandt's bat (Myotis brandtii); indeed Brandt's bat was only separated from the whiskered bat as recently as 1970 (5). Both species have shaggy fur (5), but generally speaking, the whiskered bat is darker in colour (2); the back is nut-brown, grey-brown or light brown, the belly is usually dark or light grey (2), and the wing membrane, nose and ears are blackish-brown (2). Definite distinguishing features between whiskered and Brandt's bats are the shape of the tragus, the teeth and the penis, which in Brandt's bat has a club-shaped tip (2).

The whiskered bat is uncommon in Britain, but it occurs throughout England and Wales, with a number of records from southern Scotland (7). Outside of Britain its distribution extends throughout much of Europe (2), but it is not particularly abundant (7).

Tends to occur in gardens, villages and parks, typically roosting in houses (2). Whiskered bat summer roosts are often in buildings, lofts, behind external features of houses and in bat boxes (2). Hibernation occurs in caves, cellars and tunnels (2), where they tend to hang in rather exposed sites, whereas Brandt's bats tend to squeeze into crevices and the like (5).

Bats are the only true flying mammals. In Britain bats are insectivorous (eat insects), and contrary to popular misconception they are not blind; many can actually see very well (6). All British bats use echolocation to orient themselves at night; they emit bursts of sound that are of such high frequencies they are beyond the human range of hearing and are called 'ultrasound' (7). They then listen to and interpret the echoes bounced back from objects, including prey, around them, allowing them to build up a 'sound-picture' of their surroundings (7). The whiskered bat produces echolocation calls at frequencies between 35 and 80 kilohertz (5). They emerge at early dusk, and with rapid, weaving flight they hunt over water or at low levels through woodland (2), taking midges, beetles, moths, and small dragonflies (2).

Mating tends to occur in autumn (5), but fertilisation is delayed until the following spring (7). Female whiskered bats gather into maternity colonies of 20 to 50 females in summer (7), and give birth to a single young in June or July. At three weeks of age the young bat can fly, and it is able to forage independently by about six weeks of age (5). During the summer males are solitary (7). Whiskered bats are known to live to a maximum of 19 years (2), but the average is probably closer to four or five years of age (7).

The whiskered bat, like Brandt's bat is threatened by the decline of woodland, and intensive agricultural practices, particularly the use of pesticides. Disturbance of roosting and hibernation sites may also be a problem (5).

In Britain, bats benefit from a very comprehensive level of legal protection (4). Under the Wildlife and Countryside Act of 1981, it is illegal to intentionally kill, injure, take or sell a bat, posses a live bat or part of a bat, to intentionally (or in England and Wales, recklessly) damage, obstruct or destroy access to bat roosts. Under the Conservation Regulations it is an offence to damage or destroy breeding sites or resting places. Fines of up to £5,000 for every bat affected, and up to six months imprisonment are in place for these offences (3).

For more information on the whiskered bat see: 

Authenticated (2002) by Amy Dunkley, The Bat Conservation Trust, London.

  1. Integrated Taxonomic Information System (ITIS) (October, 2009)
  2. Schober, W. and Grimmberger, E. (1987) A Guide to Bats of Britain and Europe. Hamlyn Publishing Group Limited, London.
  3. Bats and the Law - a quick guide. Bat Conservation Trust (August, 2002)
  4. Morris, P. (1993) A Red Data Book for British Mammals. Mammal Society, Bristol.
  5. Warwickshire Bat Group (March, 2008)
  6. Macdonald, D.W. and Tattersall, F.T. (2001) Britain's Mammals: The Challenge for Conservation. The Wildlife Conservation Research Unit, Oxford University, Oxford. Available at:
  7. Altringham, J.D. (1996) Bats: Biology and Behaviour. Oxford University Press, Oxford.
  8. IUCN Red List (February, 2011)