BULGARIA--Bulgaria has one of the richest bat faunas in Europe. Twenty-nine of Europe's 30 bat species are found in this small country bordering the Black Sea. The Balkan mountain chain roughly divides the country between a northern temperate zone and the comparatively wet and warm Mediterranean climate of southern Bulgaria. This geographic diversity, combined with many caves throughout the country, provides a varied selection of habitat for bats. Most of Bulgaria's bats (23 species) are cave, cliff, or mine dwellers, and the remaining six species roost in trees.
Rumiana Pandurska, a bat ecologist and BCI member, reports that beginning in the late 1980s, researchers and students from the Bulgarian Academy of Science, Institute of Zoology, began a country-wide survey of Bulgaria's bats, gathering information on their status and conservation needs. Since then, they have identified 13 critical underground roosts, some containing many thousands of bats of several species, and have discovered some 35 additional roosts. More recently, their research has focused on learning more about the behavior of cave-dwelling bats and their roosting requirements.
Data gathered over the last 30 to 40 years by bat researcher Dr. Vladimir Beshkov confirm that Bulgarian bat populations have declined by as much as 40 percent. As elsewhere in the world, the cause has been attributed to human disturbance, especially at nursery colonies. In some caves, however, bat populations appear to be on the increase. Devetashka Cave in north-central Bulgaria is now occupied by a nursery colony of at least three species, numbering in the thousands. During the 1950s, the huge cave was used for oil storage, and the high cisterns used to store the oil are still near the entrance. Although they altered the cave airflow considerably, in this case it was beneficial for bats and helped create a more favorable microclimate for nursing young.
Future bat research in Bulgaria will focus on monitoring and protecting threatened bat colonies, learning more about the ecological preferences of the different bat species in the mixed colonies, and studying the bat fauna in the caves of southeastern Bulgaria.
FRANCE--Bat researcher Philippe Lustrat reports that in the Department of Seine et Marne in north-central France, bats are in trouble because of diminishing habitat and human disturbance at their roosts, especially at hibernation sites. In the last few years alone, three species have disappeared from previously occupied hibernation sites. All bats in France are legally protected, but official interest in enforcing bat protection laws in the Seine et Marne is low, and funds are scarce for erecting bat gates over cave entrances to prevent further human disturbance.
Crevice-roosting bats like common pipistrelles (Pipistrellus pipistrellus) are trying to adapt to shrinking natural habitat; in recent years many have attempted to raise their young in the roofs of newly built houses. But most home owners are unwilling to share their new houses with bats, and Lustrat is called upon frequently to reassure frantic families and to educate them about bats and exclusion measures. Lustrat and other French bat conservationists have also put together a touring educational exhibit, available for schools.
One optimistic note is that the forest of Fountainebleau, the last remaining large forested area in the Seine et Marne, remains home to 15 of France's 29 bat species. Located south of Paris, the forest is the only known habitat for some bats in the entire region; others present there are rare even at the national level. Lustrat has been studying the bats for the past five years, the first survey of bats ever conducted in the forest.
Because of his encouraging results, the National Office of Forests and the Department of Seine et Marne are now supporting Lustrat's study, enabling him to utilize more sophisticated field equipment to identify species in flight and to track the bats to their hunting grounds. Gaining more complete knowledge of where the bats feed will be important for their protection. Lustrat hopes to locate both summer and winter roosts so that these can be protected. Fortunately for the bats of Fountainebleau, forest management had previously undertaken measures to conserve old trees for birds, which can also provide roosts for bats.
The greater horseshoe bat (
Rhinolophus ferrumequinum) is found in France and Bulgaria and most southern European countries. This species has suffered severe declines in central Europe and England and is threatened with extinction in northern Europe.