Wind turbines kill eagles, and now cameras watch for them
Wind turbines kill eagles, and doing so without a federal permit has been a crime since 1940, under the Bald and Golden Eagle Protection Act. A camera system now sits on some wind farms to stop it, scanning the sky, identifying an approaching bird, and halting a single turbine before it reaches the blades. This is called automated curtailment, curtailment meaning slowing or stopping a turbine on purpose. Boulder Imaging sells a version under the brand IdentiFlight, deployed at more than 520 stations across 6 continents since 2018. The company states outside studies found its product cuts bird deaths by more than 85%, not the same measurement as the independent result below.
Turning off a wind turbine saves eagles
The strongest evidence that this works is independent of the company. A study published in the Journal of Applied Ecology examined the Top of the World Windpower Facility in Wyoming, where a camera system detects flying objects and decides whether to curtail a turbine. The paper names no brand, so the system is not confirmed as IdentiFlight or any other named product. Researchers compared eagle deaths at that wind farm before and after installation, against a control site 15 kilometers away with no camera system, over the same years. Eagle deaths fell 63% at the wind farm with the camera system, and rose 113% at the control site with none, over the same period.
The wind farm with the camera system and the nearby control site are from the same study, compared before and after installation. The camera system in this study is not named or confirmed as any specific commercial brand.
Show the numbers
| Decline at the wind farm using the camera system | 63 |
| Increase at the nearby wind farm with no camera system | 113 |
| Overall reduction credited to the camera system | 82 |
Combining both changes, the study found the camera system cut the eagle fatality rate by 82%, with 95% confidence the true reduction sits between 75% and 89%. The authors state plainly that automated curtailment reduced fatalities but did not eliminate them, and recommend it be paired with other protections, not used alone.
95% confidence intervals from the same before and after study as chart 1.
Show the numbers
| Decline at the wind farm using the camera system | 59% to 66% decline |
| Increase at the nearby wind farm with no camera system | 51% to 218% increase |
| Overall reduction credited to the camera system | 75% to 89% reduction |
Killing 1 eagle can hurt eagles hundreds of kilometers away
A separate study in Conservation Biology explains why a single death matters so much. Researchers tracked where the golden eagles killed at 1 wind energy area in California came from, and found at least 25% were recent immigrants to the local population, most having traveled more than 100 kilometers to get there. The authors conclude that killing eagles at 1 wind facility can draw down the species across an entire continent, not only nearby birds, since the local population includes eagles that moved in from elsewhere.
The law behind the permit, and the number nobody states
The Bald and Golden Eagle Protection Act makes it illegal to take a bald or golden eagle without a federal permit, take meaning to pursue, shoot, wound, kill, capture or disturb one. A first offense carries a fine of up to 100,000 dollars for a person or 200,000 dollars for an organisation, or up to 1 year in prison, and a second offense is a felony with higher penalties. The Fish and Wildlife Service runs a wind energy specific permit track, with its own eagle mitigation calculator, weighing required conservation credits against a project hazard. The agency own program page states no national count of how many eagles wind turbines kill each year, and no other source checked here states one either. Wind turbines kill an estimated 700,000 to 1,000,000 birds a year in the United States across all species, and eagles are named among those most at risk.