Bats and wind energy in woodland I

The aims of the project are

• Identifying the function of specific woodlands as nurseries, mating and overwintering areas,
• Researching time and space patterns of bat activity with a particular focus on the activity at height in order to determine conflict areas on a regional scale (e.g. for the common pipistrelle),
• Identifying the key parameters for evaluating the disturbance effect of WT and for testing cumulative effects at the level of local populations and biogeographical regions,
• Deriving guidelines to identify conflict areas based on the findings,
• Formulating methodological standards for before-studies of designated sites and monitoring WT in woodland sites from a nature conservation angle.

Methods

First, from a study of the literature, the function of different types of woodland as nurseries, breeding and overwintering areas as well as hunting habitat was identified for all bat species occurring in Germany. Based on this, unanswered questions were identified and a total of six case studies developed.

The case studies include analysis of large data sets in order to identify important habitat factors and bat activity patterns. A range of data was analysed:

• Nursery sites for developing distribution models,
• Data from acoustic activity measurements close to the ground to determine factors affecting bat activity (landscape parameters and weather parameters)
• Data from acoustic activity measurements at different heights above the woodland to determine factors affecting activity at height.

In three case studies data was collected on activity at different heights for various species:

• At a colony of the common pipistrelle
• In nursery areas and a colony of the western barbastelle
• At a mating and overwintering area of the lesser noctule

Results

The results of the literature review and case studies were used to provide recommendations for recording methods and measures at woodland sites. The results were published in the BfN "Naturschutz und Biologische Vielfalt"-series.

In addition to the above-mentioned publication, species profiles were compiled of all native bat species. They summarise woodland use by the different species of bats in relation to threats from the construction of WTs in woodland and provide guidelines for recording and for developing measures for wind power projects. More detailed information on the above-mentioned recording methods and measures are given in the relevant chapters of the book.

The species profiles have been published on the website of the Freiburger Institut für angewandte Tierökologie (FrInaT).

A further publication resulting from data collected during the project analyses the use of roosts by the western barbastelle:

Kortmann, M., Hurst, J., Brinkmann, R., Heurich, M., Silveyra González, R., Müller, J. & Thorn, S. (2018): Beauty and the beast: how a bat utilizes forests shaped by outbreaks of an insect pest. – Animal Conservation 21: 21-30.

Further Information

• BfN | Fledermäuse und Windkraft im Wald. Naturschutz und Biologische Vielfalt 153 (in German only)
• FrInaT | Artsteckbriefe zum F+E-Vorhaben „Fledermäuse und Windkraft im Wald“ (in German only)