First Returning Kirtland's Warbler Fledgling Documented in Wisconsin
By Georgia Parham
A Kirtland's warbler that hatched in Wisconsin last year and was banded before its first migration has returned to its birthplace in Adams County, Wisconsin, marking a significant milestone in efforts to help boost its populations.
The returning bird was discovered in Adams County on June 3, by nest monitors Valarie Michel and Daryl Christensen. The bird had been hatched at the same site in 2012 and was captured and banded in August 2012 by Service retirees Ron Refsnider and Joel Trick. Refsnider estimates the chances of finding this individual at the same site a year after hatching was less than 15 percent.
Chris Mensing, endangered species biologist with the Service's East Lansing Field Office, said, “It's exciting to see Kirtland's warblers returning to habitat in Wisconsin. With endangered species, you never want to put all your eggs in one basket. Having a successful breeding population outside the core Kirtland's warbler range in Michigan helps protect the species from catastrophic events.”
The Kirtland's warbler was listed as an endangered species about 40 years ago, when its population dropped to about 300 birds. Until 1995, Kirtland's warblers were found almost exclusively in the northern Lower Peninsula of Michigan and were struggling to recover from a steep decline in populations in the 1960s and 1970s due to habitat loss and trouble from brown-headed cowbirds.
Starting in the late 1990s, the protections and efforts made under the Endangered Species Act
enabled the Kirtland's warbler to start expanding its breeding territory to Wisconsin, Michigan's Upper Peninsula and Ontario. The warblers have been observed in several counties in Wisconsin, and nests have been confirmed in Adams and Marinette counties. In 2012, Kirtland's warblers were recorded in five counties in Wisconsin (Adams, Douglas, Bayfield, Vilas, and Marinette), and a minimum of 24 singing male warblers were documented in the state.
To help increase Kirtland's warblers in Wisconsin, the Department of Natural Resources, the Service and other partners now conduct annual surveys to listen and look for the birds, monitor nests in Adams County where breeding sites have been found, and set traps to keep cowbirds away from the warblers' nests. The partners also are working to maintain and expand the mix of 5- to 20-year-old jack pine trees and barrens necessary by planting the tree species.
Get current and past reports on the Kirtland's warbler at www.fws.gov/midwest/GreenBay/endangered/kiwa/Updates.html