The Fish and Wildlife Service announced the issuance of a comprehensive set of recommended guidelines (PDF) on how to minimize the impact of land-based wind turbines on wildlife and their habitat.  The Service transmitted these recommendations to Secretary of the Interior, Ken Salazar.  Secretary Salazar will review the recommendations and consider them as he directs the Service to develop guidelines for wind turbines.

The guidelines are founded on a tiered approach for assessing potential impacts to wildlife and their habitats.  There are five tiers, and each tier includes a set of questions to help the developer identify potential problems associated with each phase of a project. The goal of the guidelines is to provide a consistent approach to assessing impacts to wildlife and habitats, while still providing flexibility to deal with the unique circumstances of individual projects. 

Tier 1 – Preliminary evaluation or screening of sites (landscape-level screening of possible sites). During this stage, the developer may be looking at a broad geographic area and the questions in this tier are geared toward identifying areas or specific sites where wind energy development poses substantial risks to species of concern or their habitat and screening certain sites to avoid those with the highest habitat values. Questions in Tier 1 include are species of concern or their habitat present on the site and are there large areas of intact habitat with potential for fragmentation.

Tier 2 – Site characterization. During Tier 2, the developer has likely narrowed consideration down to specific sites. Tier 2 would include a visit to the prospective site to address questions such as: are there plant communities of concern present and are there known critical areas of congregation for species of concern. Based on the answers to the questions in Tier 2, possible outcomes include a decision to proceed to permitting, design, and construction, abandoning the proposed site, or proceeding to Tier 3.

Tier 3 involves quantitative and scientific studies to assess the potential risk of the proposed project. The information gathered during Tier 3 will provide information to design any mitigation measures, further evaluate whether the development should continue or be abandoned, or determine if post-construction studies are necessary. Tier 3 also includes information on best management practices.

The information gathered in Tiers 1-3 will determine whether Tiers 4 and 5 are necessary. The latter two tiers involve post-construction fatality studies and other studies to evaluate the direct and indirect effects on species and habitat.

The guidelines provide specific information for each tier to help evaluate risks of adverse impacts to species, included endangered species.