Producing energy of any type has impacts on local, regional, and global bird and bat populations. Globally, the impact of wind energy on wildlife is likely less than cradle-tograve impacts of fossil fuels and nuclear power. Annual avian fatalities from wind power are also likely significantly less than the combined impacts of all other anthropogenic sources such as global warming, contaminants, habitat loss, buildings, cats, and cars.
While wind energy may partially mitigate the effects fossil fuels have on global warming, it does introduce a new stressor to specific bird and bat populations. Many of the potential impacts of wind farms, however, can be significantly reduced through proper siting and mitigation measures. This paper reviews many of the scientific studies that are ongoing in Europe as well as recommendations proposed by researchers to minimize potential effects.
Throughout the scientific literature there are three consistent conclusions: 1) proper siting of wind farms can significantly reduce avian impacts; 2) pre-construction baseline survey work is critical to ensure proper siting; and 3) there is great site, species, season, and weather variation. These observations are particularly germane to Maine, which supports regionally significant bird and bat populations, and where Governor Baldacci’s Ocean Energy Task Force (OETF) is saddled with the challenge to identify five test sites for offshore wind turbines by December 15th, 2009.
This large-scale planning effort that Maine is undertaking to identify these sites is similar to the Strategic Environmental Assessments (SEAs) established in Europe. The research in Europe has found that the primary impacts of wind farms—habitat loss and collision mortality—can significantly be reduced by avoiding critical habitats, such as seabird nesting areas, and sensitive raptor habitat such as eagle nests. Fortunately for the Maine process, these critical habitats are currently mapped and easily avoided.
While the best site planning will reduce mortality and habitat loss, there will invariably be impacts on birds and bats. To best assess the direct impacts, European researchers recommend specific monitoring technology and protocols that may be applicable to Maine. Additionally, the papers recommend potential adaptive management techniques such as turning off turbines when radar detects migrating birds and bats, and other mitigation measures.
Finally, because of the complexity of these issues, and the necessity to make decisions based on existing data that in many cases is limited, we recommend the formation of a Bird and Bat Advisory Board that can assist Maine law makers with the difficult decisions on where to site both test and large-scale commercial facilities. This board would be composed of state, federal, and NGO scientists and would also provide insight into pre- and post-construction monitoring to ensure that Maine efforts are congruent not only with other efforts in New England, but also with those in Europe.