This fact sheet attempts to summarize in lay terms the results of research about wind and avian and bat interactions on land. The information presented here pertains only to land-based installations using wind turbines of 40 kW (kilowatts) or larger capacity. Some findings may need to be revisited as turbine heights increase. It does not address offshore development. This fact sheet is not intended as a conclusion on the subject; rather, it is a summary as of July, 2004. The Wildlife Workgroup intends to revise the fact sheet periodically as more is learned. Additional resources are available at https://www.nationalwind.org/. Questions can also be directed to the NWCC staff at 1-888- 764-WIND.