Springville, Tenn.–Tennessee National Wildlife Refuge conducted its first successful winter banding this week, during which Refuge Biologists captured 32 gadwall in partnership with Tennessee Tech University’s Cohen Wildlife Lab.
Since 2019, the Cohen Lab has deployed over 1200 GPS transmitters to study the movements, habitat selection, and migration patterns of mallards and gadwall. These transmitters weigh only 10 grams, are solar powered, and are affixed to the duck as a backpack with comfortable elastic bands and a low profile to reduce air drag and snagging on vegetation. This ensures the greatest possible comfort and least possible detriment to the bird as it goes through all the cycles of its life—dabbling, swimming, molting, courtship, migrating, and nesting—in hopes that it will live a long, healthy life and transmit its location to researchers for years to come.
Five volunteers and two Biologists helped the Cohen Lab deploy 20 of these transmitters—12 on gadwall hens and 8 on gadwall drakes—during yesterday’s event, but 80 total transmitters have been deployed on ducks captured on Tennessee NWR since 2022! This data gives valuable insight into poorly understood areas of the ecology of mallards and gadwall, including migration timing and stopover duration, migration route(s), use of refuge/sanctuary locations (including Tennessee NWR!), and winter habitat selection.
Refuge photo.