Up on the roof: How flying a kite is part of bird research

Though researchers have studied of bird migration in general, the ability to track the journey of small-bodied birds has remained a mystery for years. Motus Wildlife Tracking System is an international collaborative research network dedicated to tracking the migration of small birds. The tracking of the birds is made possible by radio telemetry towers which read tags from animals passing nearby. Motus is dedicated to involving numerous locations in tracking a wide variety of small animals locally, regionally, and even internationally, describing their research as “the ultimate hands-on community science project.”

The museum is participating in this community project with a radio telemetry tower installed in January 2021 on our roof with the help of graduate student Katie Bird, University of Delaware professor Jeff Buler, Ph.D., community scientist Steve Cotrell, and Ian Stewart of the Delaware Nature Society. The project is funded by the Delaware Audubon Society and Delaware Ornithological Society.

Katie is conducting research in Dr. Buler’s lab at the University of Delaware’s Department of Entomology and Wildlife Ecology focusing on Purple Martins (Progne subis), and she worked tirelessly to get her equipment ready before the Purple Martins return in April.

Dr. Jean Woods, former curator of birds, helped Katie prepare for their return through regular visits to our roof to perform system updates on our tower. The tower consists of an antenna, a receiver which records the data, and a solar panel which powers the entire thing. The tower can record the compatible tags of any birds that pass by within a range of 10 miles. The radio tags used are solar powered and tiny (0.5 grams), so they can remain on the bird for its entire life and acquire the data without having to recapture the bird. Once the data is recorded, it is automatically made available to researchers. This data is what Katie will use to study the movements of Purple Martins in the early spring as they return to their colonies.

This map shows where the local Motus towers are that Katie is using for research, including London Grove Township, Bucktoe Creek Preserve, Longwood Gardens, DMNH, and the Delaware Nature Society’s DuPont Environmental Education Center.

While she awaits the return of the Purple Martins, Katie has collected data in various ways to train the receiver’s algorithm. She previously used a drone to replicate the flight of small birds, but the drone is out of commission. Katie then came up with the idea of using a kite to simulate the flight of a tagged martin. By flying a kite on our roof, Katie collected both GPS and radio data similar to the data the LifeTags will provide to the receiver.

Kite flying, algorithms, and — most importantly — patience are the main ingredients in Katie’s recipe for successful Purple Martin migration research. We will be watching closely for the return of the Purple Martins, and the data our tower collects as they fly through Delaware.