The Brandt’s bat (Myotis brandtii) is found throughout England and Wales and has only recently been recorded in Ireland as well. Brandt’s bats echolocate between 33kHz and 89kHz, sounding loudest at 45kHz. Their calls sound like dry clicks.
They have a rapid and skillful flight,flying at a medium height and often within woodland. They occasionally pick their prey off foliage and often feed near water.
They are found in all types of houses including some modern ones, but particularly in older buildings with stone walls and slate roofs. It is a crevice dweller, often roosting until hanging tiles, above soffits, in cavity walls and under ridge tiles. Brandt’s bats do roost in trees and churches, and have been known to use bat boxes. In winter Brandt’s bats are regularly found hibernating in caves and tunnels, almost always in small numbers – it is uncertain where the majority of them hibernate.
The Brandt’s bat is a small species with a somewhat shaggy fur. It is very similar to the whiskered bat and is difficult to tell them apart. The colour of the fur is dark grey or brown and has golden tips on the back. Its head and body length is 28mm – 50mm and the wingspan is 210mm – 240mm. The weight of this bat is 4.5g – 9.5g.
Some females reach sexual maturity at three months (in their first autumn) but the majority do not mate until their second autumn. Mating usually takes place in autumn, but has been observed in all winter months. Adult females form maternity colonies in the summer, giving birth to their single young in June or early July. The baby is fed solely on its mother’s milk: by three weeks it can fly and by six weeks it can forage for itself.
Brandt’s bats mainly feed on moths, other small insects and spiders.
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.