The U.S. Fish and Wildlife Service (FWS) has determined that a habitat conservation plan proposed by MidAmerican Energy is the best solution to help preserve certain bat and eagle species at the company’s wind farms.
As part of the plan, MidAmerican Energy will establish conservation funds for statewide bat and eagle programs to help bolster their populations.
After public input and extensive evaluation, the FWS released a final environmental impact statement that concludes MidAmerican Energy’s habitat conservation plan “best fulfills the agency’s statutory mission and responsibilities while meeting the purpose and need.” There is now a 30-day period for the public to review the plan, after which the agency can make a final decision to issue a 30-year incidental take permit.
The permit would allow for a limited number of incidental takes for four bat species and 10 turbine-related incidental bald eagle takes per year. Bats covered by the permit include the federally endangered Indiana bat, the federally threatened northern long-eared bat, and the non-endangered little brown bat and tri-colored bat. The bald eagle is not an endangered species but is protected under the Bald and Golden Eagle Protection Act, the company notes.
The FWS found in its final environmental impact statement that this amount of mortality is not likely to result in population-level impacts to bald eagles or bats.
“MidAmerican Energy has worked hard to identify and develop practices that help preserve bats and eagles at the company’s clean energy wind farms,” says Josh Mohr, MidAmerican Energy’s senior director of environmental programs. “Through this extensive effort, involving years of comprehensive research and detailed analysis, MidAmerican Energy has established and adopted unparalleled conservation practices at our wind farms. And that won’t change as we continue to grow our wind energy footprint in Iowa.”
Bat and bald eagle protection measures
MidAmerican Energy’s plan, first proposed in April 2018, helps protect the four bat species by modifying nighttime wind turbine operations during certain months. At four wind farms where researchers found increased signs of nearby bat activity, the company will make additional operational changes, including blade feathering, from mid-July through September. Blade feathering, or turning a blade to reduce its wind exposure, helps keep turbine blades from spinning slowly when light winds don’t blow strongly enough to produce energy.
The company will seasonally adjust the wind speed at which a turbine begins to spin and produce energy. Studies show the adjustment can reduce bat fatalities up to 58%. The changes slightly decrease electric generation output, says MidAmerican.
The plan also includes measures to reduce bald eagle impacts at MidAmerican wind farms, including educating landowners about removing animal remains that may attract eagles.
Bat and bald eagle conservation funds
Under the plan, MidAmerican Energy has committed nearly $10 million to create bat and eagle conservation funds. The funds will support statewide projects to offset impacts to the affected species and help bolster their populations.
In public comments it filed with the FWS, the Audubon Society wrote, “MidAmerican Energy’s investment in a 30-year commitment for a habitat conservation plan that covers the entire state of Iowa for their 22 wind projects to address current and potential conflicts with bald eagles demonstrates a commitment not only to a clean energy economy but also to the conservation of an iconic species of bird that is the symbol of our country, and that Audubon and our members treasure.”
Plan based on comprehensive study
MidAmerican Energy’s habitat conservation plan follows a four-year series of independent studies covering most of its wind fleet. In November 2014, MidAmerican Energy, along with the FWS and Iowa Department of Natural Resources, began the studies to determine how wind farms impact bald eagles and the four bat species. The efforts examined where sensitive bat species and bald eagles appear near MidAmerican Energy wind farms and evaluated their impacts.
The company is using the study results to enhance conservation practices for current and future wind farms. MidAmerican Energy will provide annual reports to the agency on company conservation efforts and their effectiveness.