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Endangered Species: Greater Sage Grouse
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Endangered Species: Kirtland's Warbler
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Endangered Species
Bouncing Back

As they have for eons, Kirtland’s warblers, migrating from the Bahamas, will arrive at breeding places in the northern Great Lakes in mid-May. But the state of Michigan can no longer lay claim to being the exclusive nesting place for the rare songbird. Once on the brink of extinction, the bird has enjoyed a population explosion in recent years due to the success of an intensive recovery program for this endangered species.

Scientists are elated but not surprised that the species’ ringing song is being heard farther afield. “The warblers prefer to nest in dense stands of young jack pines, and raging wildfires once kept them well supplied with habitat,” says Michigan Department of Natural Resources biologist Elaine Carlson. “Today 90 percent of the birds are found in [logged] jack pine plantations on state and federal forestlands, all within an area only 100 miles long and 75 miles wide.” Those brooding sites are limited in number and size, so it’s natural for new warbler generations to spread out to colonize other suitable areas.

The Kirtland’s warbler population had bottomed out in 1987, when only 167 singing males were heard in the annual census on the bird’s historic summer range in Michigan’s northern Lower Peninsula. But by 2003 the count had risen to an all-time high of 1,202. And the surge has continued. Last summer’s count, conducted by state and federal biologists, recorded an astonishing 1,697 singing males in Michigan, including 32 in the Upper Peninsula. Meanwhile, three Kirtland’s warbler nests were found in Wisconsin, the first ever. And another nest was located in Ontario, where the only previous breeding record dated to 1945. Two recent forest fires in Michigan could jump-start new natural habitat for the warblers. Six thousand acres of the Huron National Forest near the town of Mio, the capital of Kirtland’s country, burned in May 2006. And an additional 500 acres were charred last July. “These fires can be a tragedy for local residents when structures are lost and property burns,” says U.S. Forest Service biologist Phil Huber. “But from a wildlife and ecological standpoint, it’s a great thing. Most of the species that occur in a jack pine ecosystem are dependent on fire.” Or, these days, the logger’s chainsaw.—Les Line

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