Experimentelle Untersuchung des Kollisionsrisikos von Fledermäusen an Kleinwindenergieanlagen

Standardised and referenced acoustic monitoring reliably estimates bat fatalities at wind turbines: comments on ‘Limitations of acoustic monitoring at wind turbines to evaluate fatality risk of bats’

“…Ecological surveys, including acoustic surveys of bats, typically require only a sample of a population (Kenkel et al 1989). Sampling at wind turbine nacelles is usually extensive compared to sampling in other ecological impact assessments (Appendix S3) and, importantly, typically covers the entire bat activity period continuously -a major advantage since bat activity is often characterised by short peaks that are difficult to predict (Brinkmann et al 2011). Voigt et al (2021) argue that acoustic surveys at wind turbines are severely constrained because recorders "cover only approximately 23% of the risk zone for a bat calling at 20 kHz and 4% for a bat calling at 40 kHz".…”

“…To render mortality assessment more robust and less prone to random effects of a small sample size (e.g. extreme weather conditions), the relationships between environmental factors, bat activity and ultimately mortality are informed by a data-base from hundreds of turbines with more than 65000 detector-nights recorded during more than 10 years (Brinkmann et al 2011, Behr et al 2015. Moreover, the effectiveness of the curtailment algorithms resulting from the models has been experimentally validated at 16 turbines from eight sites (Behr et al 2015).…”

“…However, these searches are time consuming and costly, and estimates can be very imprecise under the conditions encountered, for example, at many sites in Europe (e.g. high rates of carcass removal by scavengers, and low detectability of carcasses -see Brinkmann et al 2011). Therefore, acoustic surveys at the nacelle (housing bearing the rotor) of wind turbines are increasingly used to assess the number of mortalities and to develop mitigation measures (Behr et al 2017, Hayes et al 2019, Peterson et al 2021.…”