During our field work, we made an unusual discovery – a night shelter for horseshoe bats in the hollow of a huge beech tree! Horseshoe bats are excellent flyers, but they are not able to squeeze through cracks and small openings, so they usually do not use such hiding places. In this case, the dimensions of the hollow proved to be crucial, as the entrance did not cause any problems for the animals to fly-in. Horseshoes used it only at night, and we observed up to three individuals inside at a time, spending up to several minutes there.
The example of this tree shows how important nocturnal shelters scattered in the area are for Lesser Horseshoe Bats, which are probably places of rest and possibly also mating. It is the shortage of such shelters that the forest bat huts we are erecting are intended to supplement. Our observation also adds to our knowledge of the role of hollow trees in bat conservation.