Golden eagles 'phone home'
March 4, 2014 —
If you have been lucky this winter, you may have seen a migrant golden eagle; a few visit each winter from Canada. Recently though, migrations of eagles and other raptors have incurred additional risk with the increase in the numbers of wind turbines on ridges that raptors use for orographic or ridge lift during migration.
The utilization of wind energy is a bold initiative that will help us in the quest for clean energy sources, but poorly sited wind generation projects have killed many large raptors. When a wind project was proposed for a ridge top near Walton, NY, members of the Delaware-Otsego Audubon Society (DOAS) grew concerned; their counts have shown that many wintering golden eagles used the area. Past data from Dr. Todd Katzner of West Virginia University has shown that 40% of all golden eagles that his team tagged in the East have used the region for overwintering during a multi-year study.
DOAS has launched a regional study in collaboration with Katzner and his team. Up until this year, four golden eagles have been tagged by NYSDEC in NY state; they were fitted with Argos satellite transmitters. Argos gives one to two position fixes per day, good for migratory studies, but the goal of DOAS study, according to Tom Salo, director of the project, is to get detailed flight data as well as demographic data. In flight, a golden eagle can cover a lot of distance between Argos fixes.
A new generation of telemetry is being utilized for this project to eliminate data gaps. Called GPS-GSM, the unit has an on-board GPS receiver that samples position, altitude, speed and direction every 15 minutes. The unit sends batches of collected data points to the mobile phone network as cell-phone-compatible data packets. In the event of no cell coverage, the unit stores data until the eagle gets back in a coverage area. Through fundraising and grants, DOAS has been able to obtain four GPS-GSM transmitters to deploy this winter.
In essence, these golden eagles are “phoning home,” giving researchers detailed information of what is favored ridge habitat. It is hoped with the knowledge gleaned from this study will help all involved to work together to provide clean wind energy without endangering these magnificent winter migrants as they grace deep blue skies overhead.