Comparative study of bat activity above and below the canopy in the Palatinate Forest area
Arne Jach, Diploma thesis
Study Description
All of the 18 bat species which are verified for the area of Palatinate are listed in the Red Lists of Rhineland-Palatinate, as well as in the annex IV of the FFH habitats directive as “strictly protected”.
Besides habitat loss, intensification of agriculture and construction of new roads, wind turbines are serious threads for bats. Because of the turnaround of the energy policy the number of renewable energy plants, including wind turbines, will rise even further in the next years. The city of Landau plans building up to nine wind turbines at the “Taubensuhl” in the middle of the Palatinate Forest.
Previous studies show significantly higher risks for bats to die from wind turbines which are located in closed forest areas than ones built on plain lands. On the other hand there are very few studies which examine differences in bat distribution on vertical levels in forests. Especially the area above the canopy is not studied very well. This might be important since most studies to bat activity are conducted from the ground.
My goal is find out if there are differences in the occurrence of bat species below and above the canopy or not, and therefor if bat studies from the ground can deliver representative results for all heights in the study area.
We surveyed bat activity and the availability of nocturnal insects on different representative crops in southern Palatine with respect to the vicinity to forests and settlements (putative roost). In order to get comparable data sets we performed bat activity measurements and insect trapping throughout entire nights and simultaneously on 10 sampling sites of a study area. Each of the 7 study areas comprised 8 different agricultural sampling sites as well as one in a traditional cultivated pasture and a forest respectively. In summary, our results revealed firstly, high bat activity as well as high insect availability on some of the examined sites in vegetable fields and apple orchards which was comparable or even higher than the activity in the nearby forests and pastures. Secondly, only very low bat activity and insect availability was proved for all examined vineyards.