Installation of hot boxes for conservation in the last nursery roost of Greater Horseshoe Bats Rhinolophus ferrumequinum in Austria

Abstract

The Greater Horseshoe Bat Rhinolophus ferrumequinum has experienced drastic population declines in Austria over the last decades. Several central European countries harbor only residual isolated populations, often at the brink of extinction. Consequently, conservation efforts are undertaken to improve roosting, hibernation, and foraging conditions. One of these measures, although almost unheard of in international literature, is the installation of hot boxes in maternity roosts to improve thermal conditions during gestation and development of the young and provide roosting locations covering a range of different temperature regimes. Here, we report the first installation of hot boxes as a conservation effort for bats in Austria. Through this measure, conditions in the attic of Schloss Eggenberg in Graz, the last known maternity roost of Greater Horseshoe Bats in Austria, should be maintained and hopefully even improved to conserve this last Austrian breeding population in the long run.