Deformed beaks

Something odd is going on in the bird world: an unusually large number of deformed beaks:

Federal biologists are intensifying research on a large and unexplained rise in the frequency of deformed beaks in a wide range of bird species from Alaska through the Pacific Northwest, including British Columbia. The deformities reduce the birds’ ability to feed, clean themselves and raise young, according to the scientists, from the United States Geological Survey.

NYT’s DotEarth has a report here and here.