Nathusius pipistrelle is a rare bat in the UK, though records have increased in recent years A previous migrant species, it has only been classed as a resident species since 1997.
The calls of this bat are similar to those of the other pipistrelles. However, the peak intensity of the call is lower
than the other two species. The calls can be audible to some adults and children.
Nathusius’ pipistrelles are often recorded roosting in crevices and have been found in cracks in walls, under soffit boards, fissures in rocks and tree hollows. In the UK only a small number of maternity colonies have been reported and these have been in the walls of traditionally built buildings of stone and red brick, in wall cavities and under flat roofs. The majority of roosts are located close to large freshwater lakes.
This species forages near rivers, canals, lakes and waterlogged areas, as well as in woodland rides and edges. The flight is rapid – slightly faster than that of common and soprano pipistrelles, although it is not quite as manoeuvrable, and its insect prey are caught on the wing, by ‘aerial hawking’. The nathusius feeds on medium-sized flying insects such as aquatic flies, midges, mosquitoes and caddis flies.
The Nathusius’ pipistrelle is similar in appearance to, but slightly larger than the much more commonly found common and soprano pipistrelles, and the fur on its back is longer, sometimes giving it a shaggy appearance. Its fur is a reddish-brown, occasionally with frosted tips on the belly. The ears, membranes and face are usually very dark. The head and body length is 46mm - 55mm and the wingspan 228mm - 250mm. The nathusius weighs 6g - 16g.
During the summer, females form large maternity colonies of up to 350 bats where each gives birth to a single young in June or early July. For three or four weeks the young are fed solely on their mother’s milk. After about four weeks the young are able to fly and at six weeks they are able to forage for themselves. Occasionally, maternity colonies may temporarily move location.
In Britain all bat species and their roosts are legally protected, by both domestic and international legislation.
Many thanks to the Bat Conservation Trust for sharing this information; for more detailed reading please visit their website below.