The Kirtland’s warbler is an extremely picky bird. Each spring, the bright yellow and bluish-gray songbird leaves its wintering grounds in the Caribbean and migrates to a highly specific habitat: dense clumps of young jack pines in Michigan’s Upper and Lower peninsulas, in Wisconsin and in the province of Ontario. They nest in the lower branches of jack pines until the trees grow to reach 16 to 20 feet, roughly 20 years old, but then, as the lower branches of the trees die and drop off, the birds choose smaller trees for their nests.
American Forests has been working for more than two decades with various partners in Michigan to restore jack pine, the only species in which the Kirtland’s warbler nests.
Fire was historically an integral part of the jack pine cycle, removing the bigger older trees and clearing the understory. Fire also prepares the ground for the seeds to germinate. But, modern fire suppression policies interrupted this cycle and have degraded the Kirtland’s warbler habitat. The narrow breeding range and loss of habitat caused the Kirtland’s warbler population to plummet, and they were listed as an endangered species back in 1967. In 1987, only 167 males were counted.
For more than two decades, American Forests has invested in bringing back the Kirtland’s warbler by restoring its habitat. Partnering with the Hiawatha National Forest and AuSable State Forest, we have planted more than 1.8 million jack pines on more than 2,100 acres. As a result, 2,365 males were counted in 2015, an increase of more than 1,300 percent. While the Kirtland’s warbler is still endangered, our work has given one of America’s rarest birds a real chance for survival.