Where Do the Swans Go?

On a warm July morning, David Wolfson and Tori Drake glass the waters of a shallow lake in northwestern Minnesota, using their binoculars to look for breeding pairs of trumpeter swans and their young. Wolfson, a PhD student in wildlife ecology at the University of Minnesota, leads a conservation research project to capture 40 trumpeter swans across the state and outfit them with GPS transmitter collars. 

He and Drake, a DNR wildlife technician, spot a pair feeding in the bulrushes along the shoreline not far away and hop in their jon boat. The boat glides up next to an adult swan, unable to fly because it’s molting. Its partner and their cygnet slip away to avoid capture. As the flightless swan flaps its wings, Wolfson leans over the edge of the boat, carefully clutches it, and lifts it in. Back on shore, the swan sits quietly in Drake’s lap as Wolfson fits it with a solar-powered GPS transmitter collar and a leg band.

“The transmitter will communicate swan locations to a cell tower at 15-minute intervals,” says Wolfson. He measures the swan’s head and its lower leg to estimate its size and draws a blood sample, which will provide a genetic profile and determine any exposure to lead.

Trumpeter swans were once extirpated from Minnesota, but more than 30,000 of them now grace Minnesota’s wetlands (see “Visions of Swans,” March–April 2017). “It’s an incredible success story,” says Lori Naumann, DNR Nongame Wildlife Program information officer. She credits the success to citizen donations and to partnerships with state, federal, and local agencies and organizations, such as the Trumpeter Swan Society and Three Rivers Park District.

Yet little is known about trumpeter swan ecology, migration, mortality risks, and habitat use.

The project “will pave the way for state and federal natural resource management agencies to make informed decisions about management and future trumpeter swan conservation,” says David Andersen, project coordinator and leader of the Minnesota Cooperative Fish and Wildlife Research Unit at the University of Minnesota.

Minnesotans can report collared swan observations to https://trumpeterswan.netlify.com, which shares data and maps swan movements. The project is funded by the Minnesota Environment and Natural Resources Trust Fund, as recommended by the Legislative-Citizens Commission on Minnesota Resources, and by the U.S. Fish and Wildlife Service and other sources.

At the water’s edge, near where it was captured, Wolfson and Drake release the bird. It paddles back to its family, its collar already beaming data to researchers who will follow and learn from its journeys.