By Doyle Irvin, American Forests
Try picturing the beginning of spring without birds singing. It just doesn’t work, does it? And yet, not too long ago, the Kirtland’s Warbler of Michigan’s jack pine forests was on the brink of extinction. Its big, bold, brassy voice — matched by its 5-inch, half-ounce frame — was on the verge of never being heard again.
Unlike many other endangered species, the Kirtland’s warbler’s native habitat was eliminated because humans prevented the jack pine forests from being destroyed. It wasn’t until long after fire suppression practices were first implemented that we realized that wildlife communities surviving in jack pine forests require periodic wildfire and regrowth to be at their healthiest.
The warbler especially needs wildfire, because it is extremely picky — it will only nest in trees of 5 to 20 years of age. Once trees reach a certain height, the birds will look elsewhere to make their nests. They also like to have some space: at least 1.5 acres, and even up to 10 acres. Finally, these warblers highly prefer Grayling sand, a specific soil type that the birds nest on nearly every time.
Biologists also discovered another threat to the endangered bird: brown-headed cowbirds were laying “parasitic” eggs in warbler nests, and their young monopolized the nests due to their larger size and aggression. By the time the Kirtland’s warbler first grabbed the attention of conservationists here in the United States, their nesting area had been reduced to the Lower Peninsula of Michigan. Only 167 males could be found in 1987.
Jack pine forests that experience normal levels of wildfire have a number of other species dependent on their regular regrowth and renewal, including black bears, snowshoe hares, white-tailed deer, upland sandpipers and eastern bluebirds, among others. The cones of the jack pine are encased in a resin that requires being put through a fire in order to germinate the seeds within. The truth is that these trees evolved with fire and have adapted to it, and our prevention strategies were actually hampering their survival.
The good news is that conservation efforts by public and private parties are definitely working. American Forests has planted more than 1.8 million jack pine trees to date in the Hiawatha National Forest and AuSable State Forest. Kirtland’s warbler populations have risen more than 1,300 percent! Unfortunately, when the original number is so low, 1,300 percent means that there were still less than 2,500 males counted in 2015. Want to see what’s at stake first hand? Just watch some footage of the Kirtland’s warbler.
This is a species that cannot survive without consistent commitment and conservation. This year, we, along with many individual and corporate partners, are committing to further the protection of this wonderful bird and these important trees. Join us in our mission by contributing to the Home for the Holidays campaign.