Some data on the behaviour of kites (Milvus milvus, Milvus migrans) nesting close to two active wind farms in Saxony, Germany

Abstract

Abstract The main aim of this study was to evaluate how local pairs of kites behave in the vicinity of two wind farms located in the same region (Saxony, Germany) and at farms which are to be re-powered. We observed three pairs that had located their nests close to active wind farms (a few hundred to 1500 m from the wind farm). Special attention was focused on variation in the intensity of flights and its dependence on the local landscape and to active avoidance of existing wind turbines. Observations were made at the end of the breeding time, when the young were still in the nest and shortly after fledging. Despite the short observation periods, the results seem to show clearly how differentiated the flight patterns of these birds are in relation to the landscape features around the farm. The distance from the nest to the wind farm cannot be the only measure of the level of potential wind-farm-related danger to the birds nesting close to the farm site. Distribution of flights is not random, but clearly concentrated on defined target hunting areas, while other directions are visited infrequently. In the case of both farms, the farm was rarely crossed by the Black Kites (9.9% of all flights) and very rarely (2.8%) by the Red Kites, and such crossing was observed only while the turbine rotors were not in motion or when the rotors were turning slowly (below 5 turns/min.). It may be advisable to conduct special monitoring of movement patterns at breeding time if kite nests are found close to the planned location of the wind farm.