Lesser horseshoea bat is distributed in western Ireland and south – west Britain. Larger populations in some states of Germany and in the Bavarian foothills of the Alps. Widely distributed in the Mediterranean area, occurs in North Africa and on all larger islands to Asia Minor and around the Black sea. In Asia – Kashmir, the Near East, Iran, Iraq, the Arabian Peninsula and parts of East Africa. In Bulgaria the Lesser Horseshoe bat is the most common species.1
Lesser horseshoe bat is the smallest European horseshoe bat. The horseshoe and the lancet appear very large. The connecting process is short and rounded, the sella tip distinctly elongates and is pointed in profile. They have dorsal fur that is brownish to yellowish – brown, the ventral side is paler grey – white. Flight membranes and ears are brown. The wings are very broad, short and rounded. In hibernation the Lesser Horseshoe bat wraps itself completely within the flight membranes.
Calls are quiet, they can hardly be detected from more than 5 m. The long, up to 60 ms constant-frequency parts of the calls are at 108 – 114 kHz. Frequency range overlaps with those of Mediterranean and Mehely’s Horseshoe bats.
In the north there are found in warmer lowlands, and in the south – they occur to altitudes of 2000 m. Hunting grouns are found in western Europe that are almost exclusively found in the forests. South – east Europe has tall herbaceous vegetation, hedge areas, forest-like biotopa, ditches and villages that are used for foraging. In North Africa, semi – desert areas, gardens and oases serve as hunting grounds. In Bulgaria they are found in caves and karst areas, rich in vegetation. Sedentary species – the distance from roosts is less than 20 km.
Roosts are very diverse – in caves, mines, rock crevices, large buildings, cellars and boiler rooms.
The Lesser Horseshoe bats hang separated in the roost. They hang in dense clusters only in low ambient temperatures, and in the final stages of pregnancy. The nursery colonies comprise of 10 – 200 females and the proportion of males can amount to one fifth of the animals. The young is born from the middle of June to the middle of July. From the middle of August and into September, the species swarms at caves, where the males are in majority.
The flight is agile and very close to vegetation. In the forests the species hunts in the crown areas of deciduous trees. The food consists of small Diptera, Hymenoptera, lacewings and small moths.
The application of highly toxic pesticides such as DDT and lindane led to a dramatic population decline in Germany and neighbouring countries. In the Mediterranean and the Balkans, the species is threatened by changes in landscape, habitat loss, habitat fragmentation and the negative effects of application of pesticides.
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”.