Boreal Chickadee is one of the bird species tracked in the recent study by National Audubon of climate-change impact on winter range. Minnesota has lost over 90 percent of its wintering Boreal Chickadees to northward movement, according to the study. Audubon used Christmas Bird Count data from the past 40 years from both the U.S. and Canada. It determined a line at which an equal number of birds of a particular species was reported on each side, north and south. In 1968, that line for Boreal Chickadees was almost 300 miles south of where it is now. When Bob Janssen published his 1987 book “Birds in Minnesota” he wrote that migrant Boreal Chickadees were reported “every fall” in Duluth. In addition to counting raptors, observers at Hawk Ridge in Duluth have for the past two years counted migrants of all species. Six Boreal Chickadees were seen in 2007, none in 2008, according to Debbie Waters, education director for the Hawk Ridge Bird Observatory. The habitat conditions this little bird needs are changing. Today, it can survive the weather found north of their former winter range. Other bird species reported in declining numbers here are American Three-toed Woodpecker and Bohemian Waxwing. On the other hand, 18 species are more common here in the winter than they were in 1968. They are Rough-legged Hawk, Dark-eyed Junco, Hermit Thrush, Purple Finch, Northern Harrier, Sharp-shinned Hawk, American Crow, Green-winged Teal, Ring-necked Duck, Tundra Swan, Cedar Waxwing, White-throated Sparrow, Redhead, Mourning Dove, Red-breasted Merganser, Caroline Wren, Gadwall, and American Robin. Some of these birds are staying the winter. Others are able to linger longer before moving south (if they do) because, apparently, milder weather allows them to do so. Robins are an obvious example of increased winter population: thousands of robins have been observed in Minnesota this winter, and they’re doing just fine, thank you. (The Boreal Chickadee in the photo was found last week nibbling deer parts along Admiral Road in the Sax-Zim bog area northwest of Duluth.)

This entry was posted on Thursday, February 12th, 2009 at 2:15 pm and is filed under Bird biology, Bird conservation, Bird migration, Bird records. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.