GPS collars help track trumpeter swan comeback

The successful recovery of trumpeter swans in Wisconsin, and other western Great Lakes states, is spurring a new regionwide effort to better understand the migration routes and winter habitats of these birds, the largest in North America and named for their resonant calls.

The Wisconsin DNR partners in other western Great Lakes states and the Canadian province of Ontario, corralled trumpeter swans late this summer, and outfitted dozens of them with GPS transmitters. These neck collars record the birds’ location every 15 minutes, and show where they stop to rest and fuel up during their migration, daily flight duration and where they spend the winter.

“Trumpeter swans are a phenomenal success story,” said Taylor Finger, a DNR wildlife biologist and chair of the swan committee for the Mississippi Flyway Council.

The original plan for the interior population called for 2,000 birds and the most recent population estimates were over 30,000 across the region – and that doesn’t include cygnets.

“Now, those large populations allow for, and underscore the need for, research to help reveal more about the swans’ ecology, to better inform future management for what’s known as the interior population,” said Finger.

The interior population includes birds in Wisconsin, Minnesota, Michigan, Iowa, Ohio and Ontario.

Sumner Matteson, an avian ecologist for the DNR’s Natuon ral Heritage Conservation Program and the leader of Wisconsin’s trumpeter swan recovery efforts over the past three decades, said that Wisconsin research in the early 2000s, revealed where some Wisconsin birds were overwintering.

“This regional project will give a fuller picture of trumpeter ecology, so, hopefully, it will help inform better management of trumpeter swans in the flyway,” said Matteson.

To aid this new Great Lakes regional research effort, the Wisconsin DNR has contributed eight collars, and the Great Lakes Indian Fish and Wildlife Commission (GLIFWC) has contributed two. As of Sept. 22, biologists had placed collars five birds, three in central Wisconsin, and two in northwestern Wisconsin.

“GLIFWC member tribes are excited that waabizii (swans) are again gracing this part of their native range, and we look forward to collaborating in this important study to help us better understand this culturally significant species and its needs,” said Peter David, GLIFWC wildlife biologist.

Wisconsin’s population was estimated at 5,000 trumpeter swans in 2015, and is now upward of 6,000 birds, excluding cygnets, a far cry from the 1980s, when the DNRs Natural Heritage Conservation program began recovery efforts.

Wetland habitat loss and market hunting for feathers, skins and meat, led to the extirpation of the trumpeter swan from Wisconsin, by the late 1800s. The recovery started gaining traction in 1989, after the DNR, working with many public and private partners, began collecting wild trumpeter swan eggs in Alaska, hatching and raising the birds, and releasing them into wetlands.

Matteson says this new research is an extension of the success of trumpeter swan restorations across the region due to partnerships and wetland conservation initiatives as well as the public embrace of trumpeter swan recovery efforts.

“We owe a lot of our success to earlier conservation of wetlands and to a very supportive public,” said Matteson. “I never imagined 30 years ago, that we’d have this many, and it is gratifying to see the excitement today of so many biologists and partners working on this project.”

To learn more about the project and track the locations of marked swans, visit the Interior Population Trumpeter Swan Migration Ecology and Conservation website.

Cutline: DNR wildlife biologist Jeff Williams holds a trumpeter swan that was banded for tracking, to determine migration routes and wintering habitats. Photo by the Wisconsin DNR