Birds with bill deformities

Bud Anderson sent me this photo of a red-tailed hawk with a deformed bill found in San Jose, CA.

Last month I posted a photo of a peregrine falcon with an overgrown bill that we got in at a hawk banding station in Duluth, MN. To all of us at the banding station, it looked like the bird had possibly flown into something and the bill became overgrown as a result. Not long after the photo was up I started getting emails from around the country about birds with bill deformities. I recalled a few years ago hearing about chickadees with deformed and overgrown bills showing up on Project Feeder Watch reports but didn't think anything more about it until the last month. This is an occurance that is being closely monitored. Many of the birds found with the elongated bills are in Alaska. The peregrine in our nets could have been from Alaska, it's tough to say, but the bird was a tundrius subspecies of peregrine. Here's a link to an article by Michael Hopkin of Bio Ed Online about the bill deformities. You can also read more about it at Boreal Partners in Flight and at Project Feeder Watch through Cornell University.