Wisconsin celebrates proposed removal of Kirtland’s warbler from federal endangered species list

The Kirtland's warbler, which was almost extinct 50 years ago, winters in the Bahamas and is extremely habitat-limited since it nests only in stands of small jack pines in northern Michigan, Ontario, and Wisconsin. It's recovering but it still is a rare sight. (Wisconsin DNR)

MADISON — The U.S. Fish & Wildlife Service‘s proposal to remove the Kirtland’s warbler from the federal endangered species list is another great conservation comeback story, and Wisconsin will continue its efforts to grow the tiny songbird’s population, the DNR said in a news release Thursday, April 12.

The U.S. Fish & Wildlife Service announced earlier this week its plans to remove the Kirtland’s Warbler from the federal list of threatened and endangered species. The USFWS has determined that the species has clearly met recovery goals following years of intensive habitat management, mostly in lower Michigan where the core population is found.

The species’ numbers in Wisconsin don’t yet meet the criteria to be removed from the state’s endangered species list. However, according to the DNR, Wisconsin continues to be active in conservation efforts for the species which began when it was first documented breeding here 10 years ago.

According to the release, national recovery team leaders believe the Wisconsin population provides an important backstop to the core Michigan population, and that newly established breeding areas on public land in northern Wisconsin will be important as hotter, drier conditions affect the warblers’ food supply at breeding sites in Wisconsin and Michigan at lower latitudes.

Wisconsin’s population has grown from only 11 Kirtland’s warblers and three nests documented in 2007 to 53 birds and 20 total nests in 2017. Importantly, the population has grown and its range has expanded from Adams County to also include Marinette and Bayfield counties, the release said, adding that the birds fledged a minimum of 49 and up to 63 young in 2017.

The Kirtland’s warbler was placed on the federal endangered species list about 40 years ago, when its Michigan population dropped to about 300 birds due to habitat loss and nest predation from brown-headed cowbirds.

Starting in the late 1990s, the protections and efforts made under the federal Endangered Species Act enabled the Kirtland’s warbler to start expanding its breeding territory to Wisconsin, Michigan’s Upper Peninsula and Ontario. The first nest was confirmed in Wisconsin in 2007.

To help increase Kirtland’s warblers in Wisconsin, DNR, the U.S. Fish & Wildlife Service and other partners now conduct annual surveys in seven counties to listen and look for the birds, monitor nests in Adams County and Marinette County where breeding sites have been found, and set traps to keep cowbirds away from the warblers’ nests.

The partners are also working to maintain and expand the mix of 5- to 20-year-old jack pine trees and barrens to provide quality habitat for Kirtland’s warblers and other species, says Grveles.

In 2017, DNR planted a 125-acre jack pine stand near the Brule River in Douglas County. Also, Bayfield County Forest and Marinette County Forest continued their habitat management efforts that benefit Kirtland’s warblers.

In addition to those county forests, DNR and U.S. Fish & Wildlife Service, other partners and collaborators include the University of Wisconsin, Wisconsin Natural Resources Foundation, USDA Wildlife Services, Sand Valley Restoration LLC, Meteor Timber, the Wisconsin Trapshooting Association, Bayfield, Marinette, Vilas, and Jackson County Forest Departments, and many birders and other private citizens.