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

7. Effekt of Nysted Offshore Wind Farm on Harbour Porpoises
Percent of day with porpoise sounds
Conclusions in general:
Documented strong effects of pile driving, which was hardly a surprise
Less specific effects of construction as a whole, with conflict between survey and POD-data
No effect of wind farm could be detected after end of construction period
Monitoring continues next year.
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