Large numbers of wind farms are currently being planned in the offshore environment, and the first offshore wind farms have been erected. Notwithstanding the benefits of this development, collision victims among birds are considered one of the major ecological drawbacks of wind energy. Establishing the collision risks of birds with offshore wind turbines therefore has a high priority. Measuring collisions is however not an easy task, because in contrast to onshore locations, birds that collide with turbines fall down and disappear in the sea.
In this report we review the systems that have been and are being developed to date to monitor bird collisions with turbines offshore. We also considered methods and techniques used in studies of bird collisions with other man-made objects such as power lines and aircraft. We discuss the requirements that have to be met by these systems to adequately measure collisions in the offshore environment. We discuss to what extent the various systems meet these requirements, and what their limitations are, as well as recent advances in methodologies and potential deployment options.
The project was carried out for the British Trust for Ornithology, as part of the Strategic Ornithological Support Services (SOSS) of the Crown Estate.