Satellite Telemetry Update

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Satellite Telemetry Update

March 11, 2015

Raptor View Research shares an update on their eagle satellite tracking efforts.

We’ve deployed four transmitters on adult Golden Eagles this season, for a total of 18 since 2011. We see different overwintering behavior from each eagle, with some staying in the Bitterroot Valley, and some making large movements elsewhere. We captured this male Golden Eagle on February 15. In the three days since capture, it has moved slightly south to Victor.

We outfitted this adult male Golden Eagle on January 7. On January 16, it left the Bitterroot Valley, and is now near Bonner’s Ferry, Idaho. Though relatively early, these movements may represent the start of its northern migration.

A trend has emerged from the spring tracks of 10 migratory Golden Eagles we’ve followed so far. All five of the eagles that spent summers at lower latitudes (northwestern Canada and the southernmost portions of Alaska) traveled through northern Idaho or Washington (green lines), The five eagles that spent summers at higher latitudes (northern Alaska) used routes further to the east, along the Continental Divide (red lines). Based on these observations, we would predict that the Golden Eagle currently in Bonner’s Ferry, Idaho will follow the “green” route north and end up summering in southern Alaska or northwest Canada.

This adult female Golden Eagle has been sticking close to a nest near the ranch’s northern boundary since we captured it on February 2. Most of the eagles we capture in the winter spend their summers in northwestern Canada and Alaska. We have tried for several years to catch the resident eagles, without success. We would be thrilled if this eagle ended up breeding at the nest this year!