The Kirtland’s warbler is a small gray-and-yellow bird and one of the rarest songbirds in North America. It was named after Jared Kirtland, an Ohio doctor and amateur naturalist, and is also known in Michigan by the common name of “jack pine bird.”
Kirtland’s warblers spend the spring and summer in their breeding grounds in Michigan and winter primarily in the Bahamas. They head south in early September and return to Michigan in mid-May. Kirtland’s warblers nearly became extinct. They will only build their nests in sandy soil under the low-hanging branches of young jack pine trees, which typically develop after forest fires clear the way for new growth. Decades of fire suppression that began in the early 20th century prevented this from happening, and by the 1950s, the breeding range of Kirtland’s warblers was down to a small area in the northern part of Michigan’s Lower Peninsula.
In addition, brown- headed cowbirds lay their eggs in Kirtland’s warbler nests, causing warbler parents to care for cowbird chicks instead of their own, which reduces their breeding success even further. Census numbers for Kirtland’s warblers dropped from 502 singing males in 1961 to only 201 in 1971. Through most of the 1970s and 1980s, the annual counts hovered around 200 males, twice dropping as low as 167.
The comeback of Kirtland’s warbler is one of Michigan’s greatest conservation success stories. Beginning in 1971, the Michigan DNR and the U.S. Forest Service began planting new jack pine habitat and controlling the numbers of parasitic cowbirds in nesting areas. Since then, Kirtland’s warbler counts have gradually increased.
They topped 1,000 for the first time in 2001, increased to 1,700 by 2007, and hit 2,000 in 2012. In 2015, more than 2,300 males were counted in the wild. Habitat planting and cowbird suppression has been so successful that the Kirtland’s warbler was removed from the endangered species list in 2019.
We haven't seen a Kirtland's Warbler yet but this is the year! We love about 20 miles from one of the designated wildlife refuges and we're planning to visit this May to see if we can spot one of these beauties. For more information on the management areas in Michigan - check out the Kirtland Warbler Wildlife Management Area website.
*Photo credit: Vince Cavalieri/USFWS - Photo in Public Domain.