Research on Marine Mammals Summary and Discussion of Research Results

8.7 Conclusion

Due to the multitude of planned wind farms, the consequences on the flora and fauna cannot be ascertained by considering only a single wind farm. Instead, cumulative effects must be taken into account. A reasonable interval between the construction phases of separate wind farms could be a valuable measure to minimise impacts on the marine environment. Licences for German offshore wind farms therefore contain a condition which allows the licensing authority, the Federal Maritime and Hydrographic Agency (BSH), to coordinate the construction work. It is questionable whether there will be enough alternative and adequate low-noise areas for the animals if at least parts of their preferred habitats will be covered with windmills sometime. Another moot question is whether the animals will get used to the offshore wind farms or avoid them, presumably, that is a species specific matter. Even in theory it would be very difficult to assess the long-term impacts on reproduction and population status, and it cannot be done with our current state of knowledge. So we should have a close look at the future experience gained from the large existing and planned wind farms. Moreover, further studies on the sensory systems and on such environmental factors as oceanographic parameters are essential for a comprehensive picture of harbour seal and porpoise ecology, and for an understanding of how these animals react to changed conditions.