Landscape-level screening
Wildlife and habitat are among many factors wind energy developers must consider during the prospecting phase of a new wind project. As developers are scouting within the larger landscape for sites with adequate wind resources, landowner interest, access to transmission and markets, and other criteria, they are also conducting desktop analyses to avoid areas of high ecological sensitivity, including:
- Large blocks of intact native landscape, such as grasslands or forests
- Habitat used by fragmentation-sensitive species for different lifecycle stages
- Migration corridors and stopover habitat
- Wetlands
- Designated refuges or protected areas
There are a variety of publicly available tools to help developers avoid high-sensitivity habitat areas. The U.S. Fish & Wildlife Service maintains national inventories of critical habitat for threatened and endangered species and wetlands. There are regional Crucial Habitat Assessment Tools (CHAT) available for the Western and Southern Great Plains regions, as well as state-specific CHATs, like this one for Pennsylvania. The Nature Conservancy has created a Site Wind Right mapping tool that incorporates data sets on wind resources, wildlife habitat, current land use, and infrastructure to help inform siting decisions across the 17 central wind belt states where the much of the U.S. wind energy potential is concentrated. Links to these and other regional, national, and state-level tools can be found on the wind energy siting resources page of REWI’s website.
Site-level screening
Once the focus has been narrowed to a potential project site, the next step in avoiding adverse impacts to wildlife is for a biologist to conduct a reconnaissance-level site visit as described in the U.S. Fish and Wildlife Service Land-Based Wind Energy Guidelines, p. 14. The purpose of this visit is to confirm the presence of any critical habitat and conduct an initial assessment of the presence of species of concern. Normally one visit is sufficient for this preliminary assessment but depending on the species and conditions under which the habitat in question might be used, it may be necessary to visit at a specific time of day or during more than one season of the year.
The outcome of site screening may be to proceed without further study if there appears to be a low probability of impacts, or to abandon the site if it presents a high probability of significant adverse impacts to species of concern or their habitats that cannot be adequately mitigated. In most cases, site screening will disclose some probability of adverse impacts to wildlife or habitat, at which point more detailed field studies will be needed to determine whether to proceed and what measures might be taken to avoid or minimize adverse impacts, as well as to provide a baseline for evaluating the effectiveness of those measures.