Two new studies imply the Golden Eagle cannot survive more wind turbines
By RANGE magazine contributor David Wojik
The Bald and Golden Eagle Protection Act specifically says that the Fish and Wildlife Service (FWS) cannot issue more “take” (that is kill) permits than the population can survive. Two new studies together imply that the golden eagle wind-kill taking is at that limit or beyond.
Clearly FWS must stop issuing new wind turbine take permits until it rigorously assesses this situation. No new wind turbines should be erected. Some presently in operation may have to shut down. Fortunately, new eagle kill permits are presently on hold under the President’s Executive Order, but we are also talking about the law.
The primary area of concern is the western range of the Golden Eagle. This runs from Montana, Idaho, and Washington down to the Mexico border. Note that the eagles often migrate north to spend the summer in Canada, so the more northern states see a lot more than their local winter populations.
However, the entire US population is only about 30,000 eagles, down from an estimated 80,000 in 1980, and they are found everywhere. Thus the entire country might be in need of care.
The first study is “Age-specific survival rates, causes of death, and allowable take of Golden Eagles in the western United States,” Ecological Applications, January 2022 and it is here.
The primary point is to estimate the allowable take (death rate from human action) under the law and compare that to the present death rate. Their allowable take estimate is a range with a median of 2,227 deaths per year, while their estimated actual take is actually greater at 2,572 annual deaths.
These are very rough numbers, so the basic point is it looks like we are already at the allowable take. Adding a lot of eagle-killing wind turbines could put the Golden Eagle on the illegal road to extinction. Clearly, caution is called for.
The second study attempts to quantify the wind-killing threat. The study is “Estimated Golden Eagle mortality from wind turbines in the western United States,” Biological Conservation, February 2025, here.
Their primary conclusion is this: “Anthropogenic mortality is the primary cause of death in adult Golden Eagles and recent trends indicate their population may be declining. If the current rate of growth of the wind energy industry continues, it could have conservation implications for Golden Eagle and other raptor populations.”
They use a collision risk model that combines the spatial population density of the eagles with the spatial density of the spinning blades. This captures the fact that in addition to wind turbines getting more numerous, they are also getting much bigger.
As an aside, I proposed a roughly similar approach to quantifying the increasing risk to whales from offshore wind development. Here the wind projects force the whales into areas of greater ship traffic.
See my “The whale killing study the Feds are afraid to do” here.
Also “How to kill whales with offshore wind” here.
Neither of these eagle studies is definitive; far from it. In fact, some of their numbers disagree. The point is that the Fish and Wildlife Service must itself conduct a rigorous assessment of the allowable take for Golden Eagles and the potential impact of additional wind development on that take.
The Bald and Golden Eagle Protection Act requires such an assessment because the FWS is prohibited from approving a cumulative take that exceeds the allowable limit. This takes us beyond the wind power executive order which also calls for an ecological assessment of wind power. It is the law.
The threat to Golden Eagles from wind is potentially enormous. Wind power generating capacity today is about 160,000 MW. The queue of new wind interconnection applications is around an incredible 230,000 additional MW. Much of that is within the western range of the eagle, and they are also found in every continental state.
The Fish and Wildlife Service simply must address this huge potential threat before any new take permits are issued to wind turbine facilities. Moreover, the assessment and underlying data must be made public under the National Environmental Policy Act (NEPA). This is clearly a NEPA action.
