New mapping tool helps identify and compare critical golden eagle habitats throughout the state
While bald eagles are one of the biggest conservation success stories in the United States, golden eagle populations continue to struggle in the West as they face increasing threats from energy development, lead poisoning, and habitat loss. Wyoming is a key nesting area for the species – which is where a new, free online tool called RaptorMapper comes into play.
The website was recently launched by the Teton Raptor Center in Wilson and maps important seasonal habitat for golden eagles throughout the state. In addition, the tool calculates the conservation values of different land parcels in comparison to other user-defined plots, based on their relative importance to the species.
Bryan Bedrosian is the conservation director for Teton Raptor Center and the team leader for the RaptorMapper project. He said Wyoming is “an epicenter” for golden eagles in the lower 48 – and that what happens to the birds in the state impacts the species’ success on a much bigger scale.
“We have some of the best breeding population and breeding habitat, but then we also host a huge number of golden eagles that overwinter in Wyoming migrating down from Alaska and Canada,” he said.
Bedrosian is also an adjunct senior scientist with the University of Wyoming’s Wyoming Natural Diversity Database and has studied raptors for 23 years. He said that up until this point, migration corridors and wintering habitat for golden eagles has largely gone un-mapped, especially in Wyoming.
The raptor specialist said millions of GPS points from tagged golden eagles and thousands of nest records went into creating the resource, spanning 15 years worth of data. Given the extensive range of the bird, the team worked in close collaboration with the Fish and Wildlife Service, the Bureau of Land Management, the Forest Service, and other raptor scientists and organizations throughout the West to paint as comprehensive of a picture as possible for the project.
“RaptorMapper is a data-rich product, which is amazing because it allows us to be very accurate and precise on where our projections are,” Bedrosian said.
A big goal of RaptorMapper is to help inform and direct golden eagle conservation throughout the state. With the important seasonal habitats identified and mapped, Bedrosian said the tool can help focus efforts into areas where they can have a more considerable impact.
“Twenty percent of the golden eagle’s best nesting territory is located in only five percent of the state. So these are areas where maybe we want to increase our protections, because it's the best of the best,” he said.
For example, Bedrosian said that focused application of conservation work could be especially beneficial aspower companies retro-fit their power lines to limit bird electrocutions. Instead of retro-fittinig at random, companies could assess where there might be a higher concentration of the species.
The scientist said RaptorMapper can also help energy companies and wind developers choose project sites that have less overlap with critical golden eagle habitat – which could help minimize the number of eagle fatalities throughout the state and save companies from having to pay large fines for their impacts on the birds.
“If our tool can say, there's a 50 percent risk decrease by moving over to area B than area A, that's a win for [the wind developer], that's a win for conservation, and that's a win for eagles,” he said.
In the future, Bedrosian hopes the framework and the methods of the mapping tool can be applied to other states and to the entire sagebrush biome.
“This is our proof of concept to make sure we knew we could do it. It worked well and I'd be very excited to talk to other folks about the potential of expanding this to other regions,” he said.
Given the size and weight of GPS transmitters, golden eagles were one of the first species that could be comprehensively studied and then mapped – but Bedrosian said as big data technology and tracking techniques advance, the project can also be expanded to map the habitats of other raptors.
“We want to do this for other species, which is why we didn't name it GoldenEagleMapper,” Bedrosian said. “We named it RaptorMapper because hopefully in future years, we’ll be able to add other sensitive species like ferruginous hawks or rough-legged hawks.”