Nyctalus noctula

Noctule
Noctule
Noctule

Most of Europe, central Russia, across the Urals, Caucasus, Asia Minor, the Near East, to southwestern Siberia, the Himalayas, China, Malaysia, Taiwan and Japan.1 In Bulgaria it is widespread, prefers deciduous forests.

Large bat with broad, rounded ears. The tragus is short and rounded. The dorsal fur is short, sleek rufous-brown. The ventral fur is a little lighter and duller. The face, ears and the membranes are dark. The wings are narrow and long.

The calls are with peak frequencies of 17 – 22 kHz or 22 – 29 kHz when bats are closer to obstacles. In open spaces the calls can be confused with the Greater Noctule bat and in the forests – with Leiser’s bat.

Deciduous and mixed forests, parks, gardens, villages and cities. Migratory species, passes 1500 km from summer (north) to winter roosts (south). Nursery roosts in trees are changed frequently.

Summer roosts are in tree holes. Woodpecker holes and bird houses also are heavily favoured. Males also form groups in summer, in tree holes, rock crevices or buildings. Winter roosts are in tree holes, crevices in buildings and bridges.

Nursery roosts can comprise of up to 100 females. Male groups are smaller, up to 20 animals. Winter roosts comprise 100 – 200 animals, which form close clusters against low temperatures. The females give birth in their first and males are sexually mature after one year. Females give birth to 1 or 2 young from mid – June. From the beginning of August males occupy mating roosts in tree holes and use songs to attract females.

 The flight is fast and direct at heights of 10 – 50m. Rapid dives to seize prey. The bats hunt over water bodies,meadow and street lamps. The food consists of Diptera, moths, beetles and bugs.

Roosts are lost with building renovations, habitat loss and pesticides use. Wind turbines are dangerous for the migration of the species.

Christian Dietz and Andreas Kiefer (2014), “Bats of Britain and Europe”;

Vasil Popov, Atila Sedefchev (2003), “Mammals in Bulgaria”;

Vasil Popov, Nikolay Spasov, Teodora Ivanova, Borqna Mihaylova and Kiril Georgiev (2007), “Mammals important for conservation in Bulgaria”.