Detailed nature conservation surveys for wind farms: birds, bats, amphibians and more

Ecological surveys for wind farms record birds, bats, amphibians and more and create the basis for the permit for your wind farm.

Anyone who builds today plans with responsibility for nature and biodiversity. We survey avifauna, such as owls, as well as bats, reptiles, amphibians, insects and biotope types. This produces an ecologically viable project. The results show which species occur, how they use the area and where the project could trigger conflicts. From this, turbine locations, timing and measures can be derived before the authorities impose conditions. The results are documented in reports that authorities and experts can follow. Technology and nature work together from the very beginning.

For birds, the study area depends on the project. The BirdLife guideline distinguishes a planning area around the wind farm and a larger assessment area, in which far-ranging species such as birds of prey are also considered. Standard circles with a radius of 500 m are meant to cover the area completely. Following the if-then principle, further surveys follow, such as a nest mapping, as soon as the terrain is hard to survey or a suspicion arises. There are separate recommendations for bird migration, and different standards apply in the Alpine region than outside it. The distance criteria of the guideline are designed as precautionary worst-case assumptions. Deviations must be well justified in the procedure, because guidelines are not binding standards. Recommendations for surveying and interpreting bird migration have existed since 2016, and for bats and wind energy there is a position paper from 2022.

For bats, activity in the rotor area is recorded and evaluated as a function of wind speed. This makes it possible to identify periods with elevated conflict potential, and operating restrictions can be defined in a targeted way. Why bats collide with wind turbines is still partly unclear; there are indications of air turbulence and noise emissions. If roost trees exist, time restrictions, ecological construction supervision and replacement roosts come into consideration for clearing. Depending on the procedural stage, the surveys serve different purposes: a risk potential analysis estimates the permitting risk, the environmental impact statement (EIS, UVE) addresses the significant effects on the relevant protected assets, the strategic environmental assessment (SEA) is geared in content and depth of assessment to the respective procedure, and the Natura 2000 compatibility statement examines neighbouring protected features. In addition, the species protection requirements from the Birds Directive and the Habitats Directive must be observed.

Technical standards are lived practice for us: the BirdLife guideline, surveys according to Südbeck et al., the RVS, vegetation mapping according to Braun-Blanquet and monitoring of amphibians and reptiles in line with the Habitats Directive. Behind this are expertise, many years of experience and a keen sense of ecological relationships. A first assessment is already provided by the preliminary nature conservation assessment and risk analysis. The results feed into the nature conservation specialist contribution for wind turbines. In Germany, the special species protection assessment (saP) applies. During construction, environmental construction supervision secures compliance with the conditions.