Chickadee with deformed bill

A Black-capped Chickadee with a severely deformed bill has been seen in Maple Grove.

Black-capped Chickadees in Alaska and the Pacific Northwest have for years been reported with this condition. Other species of birds in those areas also suffer from this condition: Northwestern Crow, Red-breasted Nuthatch, Black-billed Magpie, Downy Woodpecker, and Steller's Jay. (Curiously, the condition has not been seen in either Boreal or Chestnut-backed chickadees.) Studied since 1999, researchers have yet to find an explanation for the deformity.

I know of no such sightings for Minnesota. Now we have one. A birder in Maple Grove recently sent me this photo. The chickadee has been seen at his feeders since late December. He said that the upper mandible seems to be growing.

Here is his photo. Information on this condition can be found at
http://alaska.usgs.gov/science/biology/landbirds/beak_deformity/index.html