Atlas der Säugetiere Nordrhein-Westfalens

Großes Mausohr

1241 entries

Greater mouse-eared bat

Rote Liste NRW: 2 Stark gefährdet

  entry

Myotis myotis

The largest German bat, with a wingspan of up to 43 cm, has a brown back and a white underside. Juvenile animals are coloured rather more greyish. For its food, carabid beetles, which are captured on the ground, are of special importance.
The nursery colonies of the Greater Mouse-eared Bat are usually located in large buildings with spacious attics such as in castles and manor houses. However, large nurseries in single-family homes are also known, as well as a nursery colony with over 300 females between roof tiles and interior siding of an attic converted to living space. The nursery colony populations display great philopatry. Even reconstruction measures are tolerated if the entrance location remains unchanged. For hibernacula, all kinds of subterranean spaces are used. In the roosts, Mouse-eared Bats usually hang freely on the wall or ceiling and are easily seen during controls. Especially towards the end of the winter (in March), Mouse-Eared Bats can be found near the exit.
While the Greater Mouse-eared bat was still common into the 1960s, there followed a decline with a low point in the 1970s. Since the 1980s there was a clear increase in numbers in the nursery colonies as well as in the hibernacula. The populations doubled about every 10 years. But an expansion of the area with nursery colonies could not be observed. However, in the hibernacula of the Münsterland the species was found more commonly in the last few years and mating roosts in bat houses have also been verified in Münster.
In NRW, 25 nursery roosts with a total of 2800 females (as of 2005) are known. Most of them are known northeast of an imaginary line between Ibbenbüren and Brilon with a peak in Höxter County. A few other large nursery colonies are known from the Eifel, as well as the southern Bergische Land. An isolated nursery roosts with less than 10 females is located in the Lower Rhine region. The hibernacula are located mostly in the mountains, in the Eifel, the Bergische Land, Siegerland, Sauerland, Egge Mountains, Teutoburg Forest and the Wiehen Mountains. As of 2005, about 600 to 1000 Large Mouse-eared Bats have been recorded in the hibernacula in NRW. Consequently, only 10% of the extrapolated existing summer population of all Mouse-eared Bats are being counted.
In the hibernacula in Sauerland and in the Bergische Land, banded animals from nursery colonies in the Hessen and Rhineland-Palatinate have been verified.

Author

Carsten Ebenau und Carsten Trappmann

Citation

Ebenau C, Trappmann C (2024): Großes_Mausohr (Myotis_myotis).In: AG Säugetierkunde NRW — Online-Atlas of the mammals of North Rhine-Westphalia. Downloaded from saeugeratlas-nrw.lwl.org on 2024/11/21