There and Back Again—The Journeys of Two Wood Thrush

The migration journeys of Vermont’s neotropical migrants—birds that breed here in the summer and winter in the tropics—are arduous, with birds often flying thousands of miles to their wintering grounds and back. Wood Thrush are no exception, spending their summers breeding in the eastern half of the United States and Canada and migrating to their wintering grounds in Central America. Unfortunately, this species has declined 45% between 1966 and 2023, largely due to habitat loss. A critical element of Audubon’s habitat conservation goals involves strengthening the ties between the places birds need across the hemisphere. As a result, knowing their migration routes is integral to supporting this species throughout the entirety of their life cycles—breeding, migration, and wintering.

In 2024 and 2025 Audubon Vermont was part of a range-wide migration tracking project undertaken by the U.S. Fish and Wildlife Service. With the help of Audubon Conservation Interns sponsored by the University of Vermont, Audubon Vermont Biologist Mark LaBarr placed small transmitters called nanotags on 18 Wood Thrush in Vermont. Nanotags transmit a signal that is picked up by specialized antennas and receivers affixed to stationary towers across the Motus Wildlife Tracking System. As the tagged individual passes a tower during migration, its location is recorded as well as the date and time of the encounter. More than 1,000 Wood Thrush were tagged as part of this study and the resulting information will contribute to full lifecycle conservation efforts of this declining species.

Three of the six Wood Thrush tagged in 2024 left Vermont in the fall and returned the following spring. Four of the 12 individuals tagged in 2025 left Vermont and returned to Vermont in 2026. Additionally, several individuals were picked up by towers in both years and partial migration routes were identified. This information along with information from other states will be included in the USFWS final analysis.

Let’s follow the migration journeys of two of the tagged Wood Thrush that went there and back. The first, tag #56656, a second-year male named Debby in honor of former Audubon Vermont Board Chair Debby Bergh was tagged in Shelburne in 2024. Like most of Vermont’s tagged Wood Thrush, his migration path stretched along the east coast. By late September, Debby had started his southern migration to Central America, traveling through New York, Pennsylvania, Washington DC, and Georgia. He wasn’t detected again until late April 2025 when he left Belize and started heading north. One week later Debby was detected in Ohio, then New York, and eventually picked up at the Motus tower at Shelburne Farms—close to the site where he was originally tagged.

The second bird, tag #64897, a second-year female named Pete after Conservation Intern Pete Patrick, was tagged here at the Green Mountain Audubon Bird Banding Station in June 2025. Her fall migration took her south through Pennsylvania, North Carolina, and Georgia. Her last detection that year showed her moving south through Florida. In early May 2026 this Wood Thrush was picked up again as she started her journey north through Georgia, Washington DC, and Pennsylvania before finally arriving back here at the Green Mountain Audubon Center. Although we don’t know her final winter destination, we suspect that, like Debby, she made the flight across the Gulf of Mexico to winter somewhere in Central America.

Debby and Pete are just two examples of the extraordinary migratory journeys Wood Thrush make each year.  The data from their nanotags and others like them help answer important questions about bird migration. By better understanding these pathways, biologists can focus conservation efforts on locations critical to Wood Thrush survival. We will continue to highlight some of these movements in the future and relay the final results of this range-wide study that Audubon Vermont was fortunate to be able to participate in.