David's mouse-eared bat
Myotis davidii (Peters, 1869)
Vespertilionidae
Least Concern
| Other names | |
|---|---|
| Catalan | Rater de bigotis de David |
| Spanish | Murciélago ratonero de David |
| English | David's mouse-eared bat |
| French | Murin de David |
| Basque | David saguzar |
| Galician | Morcego de David |
Description
Slightly larger than Brandt's bat (Myotis brandtii) this species presents a head-body length between 38 to 50 mm, a forearm length between 31 to 37 mm and weighs from 4 to 7.9 gr. The dorsal pelage is dark brown, ossasionally reddish brown in some areas with hairs presenting paler tips. The ventral pelage is paler and grayer.
The taxonomy of this small bat has varied a lot in the last decades. It was previously included as a subspecies of the whiskered bat (Myotis mystacinus) of which was separated based in morphological characters. The eastern european populations were previously separated into the steppe whiskered bat (Myotis aurascens) based on ancient genetic introgressions of whiskered bats, but are currently included as Myotis davidii. European populations of David's mouse-eared bat look very similar to the south-east European subspecies of the whiskered bat, the Balkan whiskered bat (M. mystacinus bulgaricus), with similary relatively large feet and mixed skin colouring. Unlike it, the steppe whiskered bat presents a shorter muzzle and narrower ear tips. Currently, clear separation between both species is only possible using genetics.
Distribution
This widely-distributed species is found from Albania and Greece (including Crete) in south-eastern Europe, north to south Ukraine and southern Russia, the Caucasus, Turkey and northern Iran through central Asia up to Korea. Isolated populations are found in Croatia and Turkey.
Roosts and phenology
Maternity roosts recorded in construction joints of bridges and in rock crevices. It forms mixed nursery colonies with the Balkan whiskered bat (Myotis mystacinus bulgaricus), which conform most colonies. Roosts are also shared with Nathusius's pipistrelle bats (Pipistrellus nathusii). In early June females are clearly pregnant, with births taking place from the middle to the end of June.
In Europe it winters in caves, with recorded aggregations of up to 15 individuals. In the southern parts of its Asian range it probably does not hibernate.
Habitat and diet
It is found in floodplains, forests, mediterranean scrubland and steppes, mostly in open habitats. In Turkey also found in riparian areas, often found near water bodies. In the Caucasus it is found in mountain steppes up to 2,000 meters above sea level and up to 3,015 in central Asia.
In Turkey it has been found to feed mainly on spiders and dipterans, including chironomids, but also on trichopterans.
Echolocation
Its echolocation calls are similar to the whiskered bat (Myotis mystacinus), presenting short frequency-modulated pulses with a duration of 1.7 to 5.9 ms, starting between 81.1 to 112 kHz and ending at 27.3 to 34.8 kHz, with peak frequencies between 42 and 55 kHz. It is included into the Myotis 50 phonic group.
Status
According to the IUCN Red List and the Red List of UE 2007, this species is considered as Least Concern, but with an unknown population trend. These bats are protected by national laws and directed by the Eurobats Agreement, the Bern Convention and the EU Habitat and Species Directive. While the species is common in some parts of its distribution, population size has not been quantified. In its known distribution, roost loss is the only threat recorded.