Wanderings of eagles online, thanks to GPS transmitters

FRANKFORT, Ky. — Researchers and wildlife enthusiasts can now go online to track the movements of two bald eagles hatched in Kentucky earlier this year.

Last May, biologists fitted a male and a female eagle with satellite transmitters while both birds were still in their nests at Ballard Wildlife Management Area.

We wanted to find out what happened to young Kentucky eagles after they left the nest, said Kate Heyden, avian biologist for the Kentucky Department of Fish and Wildlife Resources.

Tracking patterns

Young eagles tend to wander around until they reach nesting age. The transmitters will provide us information on their dispersal, roosting and foraging patterns.

Heyden said this is the first bald eagle satellite tracking project tried in Kentucky. Each eagle has a 2-ounce GPS transmitter strapped to its back with a Teflon harness, rigged around the bird’s body and wings like a backpack.

The devices are light and unobtrusive enough that they will not interfere with the birds foraging, flying or other ability to nest. Tiny solar panels recharge the transmitter battery.

If all goes well, each transmitter should last three-five years. Heyden said the eagles early movements are informative. Although each eagle came from a different nest and left the Ballard area a month apart by September they had both relocated more than 250 miles north to northern Illinois.

Locations

At times, the birds have been located within 20 miles of each other, along the Illinois River. The male eagle recently ventured west to the Mississippi River, but quickly returned to the same area near the Illinois River, where he has spent the bulk of his time since he has dispersed.

Wildlife watchers can track the latest movements of both birds online at: http://fw.ky.gov/baldeagletracking.asp.

Locations of the birds are taken hourly, but the data is received and updated on the website at three-day intervals.

Experts from the Center for Conservation Biology, College of William and Mary and Kentucky Fish and Wildlife custom-fitted each eagle with its GPS transmitter. The U.S. Army Corps of Engineers funded the project.