LANSING, MI - The population of the Kirtland’s warbler – a bird that breeds in northern Michigan – continues to bounce back.
The Michigan Department of Natural Resources said last week a recently released annual survey shows the bird’s population is at a record high.
Researchers and volunteers in Michigan counted 2,063 singing males during the official 2012 survey period – up from 1,805 males a year ago. That’s the largest single-year increase since 2007.
The lowest numbers were documented in both 1974 and 1987, when 167 singing males were found.
Only males sing. The DNR figures that each male has a mate with him, so the breeding population is generally considered to be twice the count of the singing males.
Michigan has made special preservation efforts to help the warbler, which is considered endangered.
"We are witnessing a conservation success story," DNR endangered species coordinator Dan Kennedy said in a statement.
The birds were documented in 12 northern Lower Peninsula counties: Antrim, Alcona, Clare, Crawford, Iosco, Kalkaska, Montmorency, Ogemaw, Oscoda, Otsego, Presque Isle and Roscommon.
Birds were documented in the following Upper Peninsula counties: Alger, Baraga, Chippewa, Delta, Luce, Marquette and Schoolcraft.
The largest populations were in Ogemaw and Oscoda counties.
Birds also are found in parts of Wisconsin and Canada.
The Kirtland’s warbler is a half-ounce, yellow-breasted bird with a bluish gray face and back. It favors Michigan in the summer months and migrates to the Bahamas for the winter.
Population surveys generally are taken in mid-June, when the birds are defending their nesting territories. Kirtland’s warblers typically nest on the ground in stands of jack pine between 4 and 20 years old.
State and federal officials have worked to promote that habitat. Roughly 3,000 acres of jack pine trees are harvested and replanted each year on state and federal land.
The warbler song can be heard a quarter-mile away. The bird has such a devoted following that in past years some have lobbied to try and make it the official state bird of Michigan.
The robin is widely considered Michigan’s official state bird, based on a resolution from 1931.