Mediterranean Horseshoe Bat
Rhinolophus euryale Blasius, 1853
Order Chiroptera
Family Rhinolophidae
Conservation status: in Bulgaria: Vulnerable VU [A2c], BDA-II, III; International: IUCN-VU [A2c], BeC-II, III, BoC-II, HD-II, IV.
General distribution. Southern Europe, in the east through Transcuacasia to Iran and Turkmenistan, the Mediterranean islands, Northern Africa.
Distribution and abundance in Bulgaria. The most widespead and most numerous of the three species of "medium-sized" horseshoe bats on the territory of the country [1]. It is known from over 100 localities [2], most of them being between altitudes of 0 – 700 m, but it has winter shelters at higher altitudes as well. Its frequency declines to the south. The minimal summer population size is about 40 000 individuals. For the cave-loving species of bats, to which the Mediterranean horseshoe bat belongs, a decrease of the numbers of 20-40% at the average was registered in the 1988-1992 period with respect to the 1955-1971 period [3].
Habitats. Forested lowland karstic regions close to water. It is almost entirely linked to caves, but in non-karstic regions in the summer it also settles in buildings [4, 5].
Biology. It mainly feeds on nocturnal butterflies. Of the nursery colonies known until now, 18 are in natural caves and one is in the underground tunnels of a building [2]. The maximum of birth-giving is in the period 20 June – 10 July. The winter colonies are numerous: in caves and less often in artificial galleries. It does not migrate at large distances but makes regular seasonal trips between the summer and the winter shelters (10-60 km).
Similar species. Mehely's horseshoe bat (Rhinolophus mehelyi) and Blasius' horseshoe bat (Rhinolophus blasii).
Negative factors. Anthropogenic influences on the shelters, the hunting habitats and the flight corridors, destruction and fragmentation of natural deciduous forest habitats. Important shelters such as the caves Orlova chuka and Magura have been the object of increased tourism that does not conform to the requirements of the preservation of bats. Urbanization also exerts a negative influence.
Conservation measures taken. The species is protected according to the Biological Diversity Act, EUROBATS and all the other conventions (without CITES). Many of the underground shelters fall within different categories of protected territories. The inclusion of the known shelters in the Natura 2000 network of protected zones is to be effected.
Conservation measures needed. Preservation of underground shelters. Working out detailed management plans for those that are declared protected territories. Discovering "interim" (spring and autumn) copulative shelters (swarming sites) and concrete hunting habitats and flight corridors, so that they too should be protected. Inclusion of the known shelters in the Natura 2000 network of protected zones. The complex conservation approach requires the preservation of the habitats within a radius of at least 5 km from the summer shelters. Continuation of the yearly monitoring in the significant underground shelters of bats [6].
References. 1. Popov & Ivanova, 2002; 2. Benda et al., 2003; 3. Beshkov, 1993; 4. Petrov, 2001; 5. Beron et al., 2000; 6. Ivanova, 2005.
Authors: Vasil Popov, Teodora Ivanova
