And the answer is... Inappropriate altitude causing adverse proximity to Wind Energy Conversion features

The U.S. Fish and Wildlife Service is asking for help in investigating the death of a golden eagle found in January near a turbine at a wind farm built recently in the foothills of the Sierra Nevada range about 12 miles northeast of Tehachapi.

“We are asking individuals as well as wind energy companies with information or knowledge about the death of eagles that may have been killed due to contact with wind turbines to contact us,” said Jill Birchell, special agent in charge of the agency’s law enforcement office for California and Nevada.

 [Service Seeks Information on Eagle Deaths at Tehachapi Range Wind Farms]

 Cartoon from Windtoons.com