Cooperative Fish and Wildlife Research Units Program: Idaho
Education, Research and Technical Assistance for Managing Our Natural Resources

In southern Idaho, the U.S. Air Force conducts aviation military training and combat simulations. These combat simulations involve jet planes flying at low altitude and high speeds focused around two bombing ranges and a collection of emitter stations in Owyhee County. These installations and flyovers occur through greater sage-grouse habitat. Since 1965, greater sage-grouse have experienced a range-wide population decline and are impacted by other types of noise disturbance and human infrastructure. The military has restricted use of some emitters to minimize impacts on sage-grouse attending leks, but we lack information on the effectiveness of these restrictions, or the impacts of intermittent noise on greater sage-grouse. In addition, low-altitude flyovers occur outside of these restrictions, and their impacts on sage-grouse lekking and nesting behavior are still unknown. The primary objective of this project is to document the effects of intermittent noise disturbance from low-level military overflight on nest survival, lek attendance, and behavior of greater sage-grouse. We placed audio recorders and cameras at sage-grouse nests and leks to document sound levels, nest survival, lek attendance, and behavioral responses by lekking sage-grouse. From 2022-2023, we attached radio collars to 53 sage-grouse hens and monitored 26 nests, recording 7,200 hours of audio. We monitored 18 leks from 2022-2023 and collected 13,247 hours of audio and 22,413 scan-sampled behavioral observations. Our results will provide insight into the effectiveness of existing restrictions on military flights near sage-grouse leks and the impacts of intermittent anthropogenic noise disturbance on greater sage-grouse.