Midwestern North America


The Upper Midwest houses one of the densest populations of breeding and migratory Bald Eagles in North America. Bald Eagles in the region use riparian areas (areas near lakes and rivers), but also regularly use upland areas away from water. Use of upland areas during the breeding and non-breeding season results in eagles encountering threats such as wind turbines, power poles and power lines, vehicles, and carrion contaminated with lead bullet fragments. The purpose of this project is to understand how external factors, such as weather and landscape characteristics, influence Bald Eagle movements in the region. Understanding movements of Bald Eagles during all life-stages is critical to manage and conserve this population in the face of expanding development.

Research Methods

We began this project in 2014 with a grant from the American Eagle Foundation. In 2015, we began collaborating with the US Fish & Wildlife Service, Region 3, Illinois/Iowa Ecological Service Field Office. Our primary method for studying Bald Eagles is telemetry. Since 2014, we have trapped and tagged 30 migrant eagles during winter, 6 eagles at rehabilitation facilities, and 51 nestling eagles.

Bald Eagles are tagged with light-weight GPS telemetry units that will track their movements at intervals as frequent as 4 seconds. The units provide information on location, flight speed, flight altitude and direction, activity rate as measured by an accelerometer, and other diagnostic information. This project is conducted in collaboration with scientists at the US Geological Survey and biologists and engineers at Cellular Tracking Technologies, LLC.

Specific Studies

  • Winter movements of Upper Midwest Bald Eagles into upland areas: Consequences for wind energy development
  • Understanding movement ecology of juvenile Bald Eagles in the Upper Midwest to aid management of a recovering population