Wildlife High-mounted wind turbine rotors protect red kites from collisions
Wind turbines with high-mounted rotors are safer for red kites. This is shown by a study for which around 3,000 birds from Switzerland, Austria, Germany and other countries were fitted with GPS trackers and observed for eleven years.
29.10.2025, 08:01
SDA
The findings could be used in the planning of new wind turbines, according to a press release issued by the Swiss National Science Foundation (SNSF) on Wednesday. The SNSF co-financed the study.
Of the 3,000 red kites tracked over the eleven years, 41 birds died in collisions with wind turbines. These included four of the 500 or so birds tracked by the Swiss Ornithological Institute in Sempach LU. These were killed by wind turbines in France, Spain and Germany. No such deaths were recorded in Switzerland itself.
According to the SNSF, this is probably due to the comparatively low number of wind turbines in Switzerland. Almost half of the collisions occurred in the north of Germany, where the number of wind turbines is particularly high. A further twelve collisions took place in Spain and France.
Autopsy on birds
To determine the cause of death, the researchers recovered and autopsied birds that had died in the vicinity of a wind turbine wherever possible. This enabled them to confirm a collision with a wind turbine as the more certain cause of death for 25 of the birds that died. The remaining 16 were classified as very likely or possible.
The team also analyzed near-collisions using the GPS data. This enabled them to show that the risk of collisions decreases significantly when the rotors are mounted higher. With larger rotors, on the other hand, the risk increases considerably - an increase in diameter of 25.5 meters increased the probability of a collision fivefold.
"In the future, the number of wind turbines in Europe will increase many times over. This could make this risk more significant," Martin Grüebler, Head of Ecological Research at the Swiss Ornithological Institute, was quoted as saying in the press release.
