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Gewählte Doctoral Thesis:
Claudia Elisa Kubista
(2017):
BATS: HOW AND WHERE TO FIND THEM URBAN ROOST SELECTION, HABITAT PREFERENCES AND RECORDING DEVICE PERFORMANCE.
Doctoral Thesis - Institut für Zoologie,
BOKU-Universität für Bodenkultur,
pp 149.
UB BOKU
obvsg
FullText
- Abstract:
- Twenty-eight of the 38 European bat species can be found in Austria. Many of them are listed in Red Data Books; nearly all of them are listed in Appendix IV, eight additionally in Appendix II of the FFH directive. Therefore, detecting and monitoring bat populations have become increasingly important in the last decades and a profound knowledge of their life and habitat requirements is needed. A very important resource for bats are roosts. Our findings showed that in the City of Vienna bats mainly preferred crevices in trees and buildings as roosts. A tree diameter at breast height of >40 cm was essential for suitable roosts, whereas building dwelling species showed no evidence for a preference of a particular building category. Especially the protection of rare and cryptic species like Myotis bechsteinii and M. alcathoe is challenging due to the scarce knowledge of their geographic distribution. We buildt habitat models for both species by combining data from various sources. This technique enabled us to extend the expected range of M. bechsteinii to Upper Austria and Vorarlberg, and to provide a distribution map for Austria. For M. alcathoe, we recommended to introduce the species as “Data Deficient” in the Austrian Red Data Book, but nevertheless expect it to be threatened due to its highly specific habitat requirements and small population size. A new and meanwhile indispensable method for recording bat presence is the use of automated ultrasound detectors. Since little is so far known about the factors influencing their field performance, we tested for effects of call detection ranges and vegetation clutter on the recording probability of bat calls. We found huge differences in recording performance among neighboring devices and could show that the number of vegetation strata did not play a significant role for the detecting probability, whereas the openness of vegetation did.
- Betreuer: Bruckner Alexander
- 1. Berater: Nopp-Mayr Ursula