Do windmills kill birds?

From Great Lakes Wiki

Q: Do windmills kill birds?
A: The short answer is yes, but the long answer is way more interesting and important!

Much of the concern about bird kill at wind generators comes from experience that is now 20 years old. A significant number of raptors were killed at some early wind farms located in California, and that experience resulted in a lot of concern about bird kills, known as avian mortality.

Wind generator manufacturers and wind farm developers have made many, many changes in the last 20 years, to make sure that wind farms will operate with a bare minimum of problems caused for birds or any other wildlife.

Wind generator towers have been changed so that birds no longer have places to roost.

Wind turbines have grown much, much larger, and that means the blades turn much, much slower. The speed of the tip of the blade, measured in feet per second or miles per hour, has remained fairly constant while the blades themselves have gotten longer and longer. Now that the blades revolve around the hub a lot slower, birds are apparently able to see them much better and there are fewer collisions.

Also, wildlife studies are now completed prior to the final siting for essentially all utility scale wind turbine projects. Bankers won't loan money to a wind farm developer for a project unless extensive wind speed measurement data has been collected to show the project will be successful and environmental impact studies have been completed to make sure there won't be any serious land-use problems, including watching out for bird and bat habitat and migratory paths.

Scientific studies in the Midwest have shown that a typical wind generator is likely to kill between 1 and 2 birds per year, and there is no reason to believe that those kills will be of threatened or endangered species. When those numbers are compared to lots of other reasons why birds get killed, wind generators do not appear very scary.

The National Wind Coordinating Committee has established a wildlife workgroup, and they publish a directory of research, publications, and related activities. You can find that updated directory here.

Learn more from:

• American Wind Energy Association
  
• American Bird Conservancy
  
• Audubon Naturalist News and National Audubon Society
  
• Wisconsin Birds Organization