Comprehensive knowledge of roosting and foraging ecology is essential for conserving bats.
Therefore, the four-year LIFE Nature programme "Conservation of three cave-dwelling bats in Southern France" included an autoecological study of Miniopterus schreibersii, a highly gregarious cave-dwelling species. In a colony of 3-5000 adults, 21 females were radio-tracked during pregnancy and lactating periods, when some of them switched roosts within a 30 km radius around the maternity colony. Every night, for about 6 hours, each bat flew far from the roost (4.1 to 29.2 km) to forage on several small feeding areas (1 to 9 over a few nights). Mean individual home-range estimation averaged 10837 ha for pregnant females, 22318 ha for lactating females. Urban areas lighted by white street lamps were used extensively. Some bats also foraged selectively in deciduous or mixed woodlands and in orchards and parks. The importance of hedgerows was confirmed. Conservation of M. schreibersii must be planned at a large scale, protecting a network of roosts nd promoting nature-friendly agricultural practices.