The best way to count the apex predator of the sky is to take to the air yourself. Each year at the end of March, the Wyoming Game and Fish Department biologists over the most densely populated bald eagle habitat in the state: the Snake, Salt and Green river drainages.
To count the eagles, we fly over known nest sites. Eagles typically build nests along major rivers and lakes that have a good supply of fish. Game and Fish biologists have learned if a bald eagle nest site is productive, the eagles will return 90 percent of the time. Eagles will live as close as a half-mile from each other, so some nests are densely packed, especially along the banks of the Snake River and some parts of the Green River. We look for the number of eagles on the nest, called “occupancy data.” Last year, we flew over 104 nests; that is of the 200-plus known territories statewide. We will fly again in late May or early June to obtain a count of the almost-fledged young and revisit nests where eggs were being incubated during the March flights. Last year, the nests surveyed produced 95 young.
It’s not a complete count of bald eagles in the state, but by resampling part of their range every year, we obtain a solid index on how this species and its habitat is doing, and we have current information for analysis required on effects of proposed developments or projects
Though the bird came off the Endangered Species List in 2007, bald eagles are still protected under the federal Bald and Golden Eagle Protection and Migratory Bird Treaty acts. Game and Fish considers it a Species of Greatest Conservation Need. The department has been collecting aerial data on bald eagles since 1978, and is the only organization in Wyoming that compiles complete survey data used by state, federal and private agencies.
To count the eagles, we fly over known nest sites. Eagles typically build nests along major rivers and lakes that have a good supply of fish. Game and Fish biologists have learned if a bald eagle nest site is productive, the eagles will return 90 percent of the time. Eagles will live as close as a half-mile from each other, so some nests are densely packed, especially along the banks of the Snake River and some parts of the Green River. We look for the number of eagles on the nest, called “occupancy data.” Last year, we flew over 104 nests; that is of the 200-plus known territories statewide. We will fly again in late May or early June to obtain a count of the almost-fledged young and revisit nests where eggs were being incubated during the March flights. Last year, the nests surveyed produced 95 young.
It’s not a complete count of bald eagles in the state, but by resampling part of their range every year, we obtain a solid index on how this species and its habitat is doing, and we have current information for analysis required on effects of proposed developments or projects
Though the bird came off the Endangered Species List in 2007, bald eagles are still protected under the federal Bald and Golden Eagle Protection and Migratory Bird Treaty acts. Game and Fish considers it a Species of Greatest Conservation Need. The department has been collecting aerial data on bald eagles since 1978, and is the only organization in Wyoming that compiles complete survey data used by state, federal and private agencies.
Publish Date
Answered By
Susan Patla
Job Title
Non-game biologist
Photo
Ask Game ID
134
Node order
173
Parent Node
1135