A quarter-mile buffer between wind turbines and nests won’t keep raptors from being killed by the proposed Horse Heaven wind project in southeast Washington, state wildlife biologists say.

A buffer would only minimize disturbance to nesting raptors during construction, state wildlife biologist Jason Fiddora told the Energy Facility Site Evaluation Council Nov. 29.

“That isn’t going to result in reduced mortalities after construction,” he said. “The home ranges and foraging areas of these nesting raptors will exceed a quarter mile.”

Fiddora and fellow Fish and Wildlife biologist James Watson warned the council about potential hazards if Gov. Jay Inslee approves placing 231 turbines and 5,000 acres of solar panels on rolling hills near the Tri-Cities.

Proposed by Scout Clean Energy, a Boulder, Colo., company owned by global investment firm, Brookfield Asset Management, the combined wind and solar installation would be the state’s largest renewable energy plant.

The council, made up mostly of officials connected to the Inslee administration, will submit a recommendation to Inslee, who has made permitting wind and solar projects a high priority. The project will help the state meet its clean-energy goals, according to Scout.

Turbines in hawk territories

The council’s staff has produced a report acknowledging the turbines would dominate the landscape and that the project would impact cultural resources important to the Yakama Nation.

On Nov. 29, the council heard more concerns about the project from Fiddora and Watson, who questioned the sufficiency of some of the measures proposed by Scout and the council’s staff to protect birds.

The measures largely require Scout to avoid disturbing nests and habitat if feasible and to keep track of birds killed by rotating blades. Scout and technical advisors may confer on “adaptive management strategies.”

According to one mitigation measure, Scout will try to avoid placing turbines within 2 miles of the nests of ferruginous hawks, the bird that has drawn the most attention and potential protection. Watson said hawks use more than one nest, creating territories for each mating pair. The project proposes putting turbines within 2 miles of 12 of the 18 hawk territories within the project boundary, he said.

“That’s the area I would look at as being the most critical to be protected because that’s going to be the area that they use on a daily basis, flying in and out of turbines,” Watson said.

“These birds are absolutely susceptible to turbine strikes,” he said.

Watson said recent research suggests the number of ravens and great horned owls increases around wind projects. Both are competitors and could prey on young ferruginous hawks and steal eggs, he said.

“That’s another concern we have with changes in the immediate landscape around the ferruginous hawks,” Watson said.

Another mitigation measure would be to preserve the habitat of the sagebrush sparrow, sage thrasher, Vaux’s swift and the songbird loggerhead shrike.

Fiddora said the problem is that those birds fly through the area. “They’re talking about habitat onsite and most of these (birds) are migrants,” he said. “We do know these species are going to be flying north-south.”

No golden eagle or bald eagle nests have been found inside the project boundary, according to the council’s staff. Fiddora said golden eagles and bald eagles gather on farm fields in the winter.

“This area is kind of a hot spot for wintering raptor use,” he said.

Report: Horse Heaven windmills would ‘dominate’ landscape