The Kirtland's warbler is an endangered songbird that nests in young jack pine stands. Until 1995 they had nested only in the northern part of Michigan’s Lower Peninsula. Today, they also nest in the Upper Peninsula, and since 2007, have nested in Wisconsin (links to a PDF) and Canada.
Kirtland's warblers migrate from their nesting grounds to the southeastern coast of the United States on their way to wintering grounds in the Bahamas.
Prescribed fire, clearcutting, replanting, and cowbird control are some of the measures taken to restore Kirtland's warblers and their habitat. In Michigan, most Kirtland's warbler habitat is on public land. In Wisconsin, Kirtland's warbler are often found on private lands.
Kirtland's warblers nest in jack pine stands where trees are just the right height (about 5 to 16 feet tall) and the trees are spaced to let sunlight through to the ground. Sunlight helps keep lower tree branches alive and bushy. Because Kirtland's warblers build their nests on the ground the bushy lower trees brances hide the nest beneath them. When the trees grow larger their upper branches block the sun, causing the lower branches to die. Grasses and other plants also become less dense. The warblers then must find another nesting area. After nesting and raising their young, Kirtland's warblers migrate to the Bahamas where they winter in scrub thickets.
Recovery is the process used to restore threatened and endangered species to the point that protection under the Endangered Species Act is no longer needed. Kirtland's warbler recovery has centered on managing State Forest lands, National Forest lands, and National Wildlife Refuge lands for short rotation jack pine to provide suitable nesting habitat, along with trapping and removing brown-headed cowbirds to reduce nest parasitism and increase warbler nest productivity.