Long-fingered bat (Myotis capaccinii)

French: Murin De Capaccini
Spanish: Murciélago Ratonero Patudo
GenusMyotis (1)
SizeHead-and-body length: 47 - 53 mm (2)
Forearm length: 37 - 44 mm
Weight7 - 13 g

Classified as Vulnerable (VU) on the IUCN Red List 2004 (1).

The long-fingered bat is a medium-sized bat and one of three ‘trawling’ European bat species, the other two being the Daubenton’s bat (Myotis daubentonii) and pond bat (Myotis dasycneme)(3). ‘Trawling’ bats have very big feet in relation to their body size and feed by ‘scooping’ their prey from water surfaces with their feet and the help of their tail membrane. The long-fingered bat has immense feet compared to the other two trawling species, hence its common name, and its toes have characteristic long bristles. Typical of Myotis species, this bat has an elongated muzzle. The tragus is long and narrow reaching half the length of its ear and has a pointed tip. The fur on the bat’s back is brownish-grey and is darker than that on the stomach, which is greyish white. Juveniles are characterized by relatively smaller size, lighter weight, pigeon-grey colouration on the back and dark lower lip and chin, which usually becomes pinkish at the adult stage.

This species is restricted to the Mediterranean coast, its distribution ranging from Morocco, Algeria and Tunisia in northern Africa, and Spain as its western border in Europe, extending through to Asia Minor and the Middle East from Israel to Iran and Uzbekistan in the east, including islands such as Corsica, Sardinia, Sicily and Cyprus (1) (4) (5).

The long-fingered bat feeds over the water surface of lakes, ponds, streams and rivers. It is an obligate cave-dweller, preferring warm underground sites (natural and artificial caves such as mines) in summer and cool sites in winter, using transient sites over the seasons in-between.

The long-fingered bat is an insectivorous species, typically feeding on insects with aquatic larvae such as Diptera and Trichoptera, although some recent evidence suggests that it may feed opportunistically on fish (6) (7). Individuals emit short steep broadband echolocation calls, as is typical of other Myotis species, sweeping from frequencies of 90 kHz down to 35 kHz on average.

The species typically forms colonies from several tens up to several thousand individuals, usually mixed with other cave species, most commonly Miniopterus schreibersii, but also Rhinolophus euryale, R. mehelyi, R. ferrumequinum, Myotis emarginatus, M. myotis and M. blythii, but individuals can occasionally be found roosting singly on cave walls. Very few males are present in maternity colonies, which form in summer, but mixed-sex colonies exist throughout the rest of the year. Because the species is closely associated with water, it preferably roosts near water surfaces, if such locations are available.

Mating starts in August and may continue throughout the winter and possibly early spring. Bats give birth to a single pup between April and May, after a gestation period of between six to eight weeks. They are among the first European species to give birth following winter. The pup is weaned after a period of approximately four to six weeks.

The exploitation of caves as tourist attractions is a major threat to this species, which is an obligate cave-dweller. The bat’s restricted distribution to the Mediterranean coast of Europe implies very specific ecological requirements. Not all available underground sites are suitable for roosting. The distribution and abundance of suitable sites for roosting, and the loss thereof, may have a significant effect on the distribution and size of this species’ populations. Degradation and loss of suitable water habitat (e.g. pollution of rivers and lakes) is also a threat to the species, by affecting insect populations on which the bat feeds.

Scientific research into the complex ecological needs of this little-known bat is being conducted in Spain and France (8) (9) and has recently been conducted in Greece (10). This research will help identify priorities for the conservation of the species.

Written and authenticated (24/01/2007) by Eleni Papadatou, Institute of Integrative and Comparative Biology, University of Leeds.

  1. IUCN Red List (December, 2009)