Teresa Schumacher

Teresa Schumacher


Comparison of Bat Activity and Bat Communities in Montane Old-Growth and Managed Forests.

Forests are important habitats for bats and bats play important roles in forest ecosystems. Especially in old-growth forests bat activity is often higher than in less structured ecosystems, due to a higher resource supply (food and roosts) and a higher number of available niches. The present study was carried out in and up to 10 km around the Wilderness Area Dürrenstein, the only “Area of the Wild” (Category I, IUCN) in Austria. The goal was to compare bat activity and the composition of bat communities between old-growth and managed forests. An automated acoustic sampling of bat calls with batcorders (ecoObs, Nuremberg, Germany) was carried out. Nineteen sampling points were located in the old-growth forest and compared with 19 points, matching in their elevation above sea level, in surrounding managed forests. This way, a total of 1370 bat passes were recorded which could be assigned to at least nine different bat species in each forest management type. We observed differences in bat activities between the two forest management types for a few commonly recorded species or species groups [Barbastella barbastellus, Myotis brandtii/M. mystacinus, Mkm (Myotis daubentonii, Myotis brandtii/M. mystacinus or M. bechsteinii) and Pipistrellus pipistrellus]. No significant difference in overall call activity and the species number could be detected. However, bat species composition varied between the two forest management types. Furthermore, bat activity was positively related to the structural complexity of the forests around the recording sites. Our results confirm the importance of upright dead wood and large trees in forests. Thus, these structural characteristics should be primary goals if bats are conservation targets in forests. Moreover, not only bats would benefit from these management measures.

Link to the E-Thesis