Offshore Wind Farms and the Environment

1. Offshore Wind Farms and the Environment Ib Krag Petersen, Jakob Tougaard and Jens Kjerulf Petersen Danish National Environmental Research Institute, Kalø

2. Which are the environmental issues? • Marine invertebrates • Fish • Birds • Marine Mammals

3. Marine Invertebrates • Introduction of novel habitat • Potentially increased biodiversity • Potentially increased invertebrate biomass • Potentially introduction of invasive species

4. Fish • Potentially increased fish stock due to novel habitat • Potentially incresed fish stock due to reduced commercial fishery • Potential creation of barriers from magnetic fields along power cables

5. Birds • Potential collision risk • Direct loss of habitat • Indirect loss of habitat

6. Long-tailed Duck Red-throated / Black-throated Diver Pre- and Post-construction Encounter Rates

7. Percent of day with porpoise sounds Effekt of Nysted Offshore Wind Farm on Harbour Porpoises Reduced numbers both during construction and post-construction. Effect inside WindFarm 6 times higher than in reference area. Effect seen after one year of operation. Effect less at Horns Rev. Carstensen et al (2006)

8. Which are the challenges we face in order to secure sustainable development of offshore wind farms? • gain experience from a variety of wind farms • national and international strategic planning, including spatial planning • tackle the issue of cumulative effects • produce knowledge on habituation • increase knowledge on interactions between trophic levels • weighing local effects on nature against benefits to saving the planet

9. Thanks for your attention