The sun is just up and a team of Department of Natural Resources wildlife staff, a retired DNR biologist and a US Fish and Wildlife Service employee have gathered at an intersection in state forestland in Foster Township in Ogemaw County. It's early June and time for the annual ritual of counting the birds singing in the jack pine stands. But not just any birds.

State and federal wildlife workers spend June 6-15 of every year tallying the number of Kirtland's warbler males singing during the breeding season. The Kirtland's warbler is one of the rarest of all woodland warblers, and this is the 35th year that the DNR, other governmental agencies, and volunteers have teamed up to tally their numbers in Michigan. The Kirtland's warblers breed exclusively in Michigan, though singing males have been confirmed in Wisconsin and the province of Ontario. Ogemaw County's Foster Township is the heart of Kirtland's warbler habitat in Michigan.

In the spring, the Kirtland's warblers arrive from their winter habitat in the Bahamas. Traveling more than 1,200 miles, the warblers take up spring and summer residences in the jack pine stands of northern Michigan. The warblers are very picky about their nesting habitat. They nest on the ground under branches in jack pine stands five to 20 years old more than 80 acres in size. These stands are characterized by having dense clumps of trees interspersed with numerous small, grassy openings, sedges, ferns and low shrubs. The stands are used by the birds for nesting when the trees are about five feet high or about five to eight years of age. Nesting continues in these stands until the lower branches of the trees start dying, or when the tree reaches a height of 16 to 20 feet.

"(Brown) thrashers can give you fits. They drown out everything," said Jerry Weinrich, retired DNR biologist leading a novice census participant on a walk along a fuel break line bordering a jack pine stand. The brown thrashers were being quite loud this particular morning as the census began.

That's not to say that the Kirtland's warbler is a meek singing bird. The Kirtland's, in fact, is mouthy for a warbler. Its "chip-chip-che-way-o" song is loud and clear in the early morning hours. "They really like to belt it out," Weinrich says with a chuckle.

Census takers are given maps with grids a square mile in size or smaller in sections of state forestland in the Kirtland's warbler Management Units in northeast Lower Michigan. Groups of five or six walk about a quarter of a mile apart through the square mile area listening for the male Kirtland's distinctive song. Counting their paces against hash marks on the grids, the census team members mark on the maps where they heard singing males. The maps are compared after the section is walked and a team leader determines who heard the same birds in the same areas, eliminating duplication. The Kirtland's song can be heard from up to a quarter of a mile away, providing an excellent way to census birds with minimal disturbance.

Once all sections are surveyed for Kirtland's warblers, the numbers are tallied. Last year, the census counted 1,415 Kirtland's warblers. This year's census numbers will be released later in the summer, after the USFS has had the opportunity to survey the central Upper Peninsula, where 18 singing males were counted last year.

The jack pine ecosystem is vital to the breeding success of the bird. Years ago, natural occurring fires would burn jack pine stands, causing a "disturbance factor." The young jack pines on which the Kirtland's warblers depend grow after a fire has removed the older trees. Heat from the fire opens jack pine cones to release seeds and thus, rejuvenate the forest. With modern fire protection and suppression efforts, forest management practices did not emphasize the regeneration of jack pine, resulting in a dramatic decline of available warbler nesting habitat and a drop in warbler numbers.

Today, the DNR and USFS maintain about 30,000 acres of productive warbler habitat to encourage breeding. The agencies clear cut large jack pine stands after the trees have matured to merchantability, at about 40-50 years of age. The stands are replanted with jack pine seedlings grown at the Wyman Nursery near Manistique in the Upper Peninsula. The sensitive habitat is protected in the spring and summer, with activities such as firewood cutting strictly prohibited.

While clear cutting of jack pine stands has not been looked on favorably by some area residents, DNR wildlife managers maintain it is necessary to keep the endangered birds breeding and increasing in numbers.

"These jack pine stands are important wildlife habitat," said Elaine Carlson, DNR biologist in the Mio field office. "The stands provide homes for upland sandpipers, Eastern bluebirds, white-tailed deer, black bear, and snowshoe hare and for several protected prairie plants, including the Allegheny plum, Hill's thistle and rough fescue."

One unwanted inhabitant of the jack pine stands is the brown-headed cowbird, a predatory bird that lays its eggs in the nests of other birds. The cowbird chicks hatch faster than most songbirds, are more aggressive and will out-compete their nest mates for food. The USFWS is addressing the problem of the parasitic cowbird by constructing simple traps in the jack pine stands to trap the cowbirds. The trapped cowbirds are later euthanized. Any non-target species that become trapped are released unharmed. One cowbird trap can protect up to several hundred acres of jack pine habitat with an average of 4,000 cowbirds trapped each year.