Long-tailed Duck with unusual bill

On 28 February 2010, at Humber Bay Park East in Toronto, Ron Pittaway and I saw this adult male Long-tailed Duck with an unusually coloured bill. Comments welcome email

The pink on the bill is in the usual place, but the base of the bill which is normally black is a deep orange. A black line separates pink from orange.

Front view of bill. Note also black flecking on white bib.

An uneven pattern of black surrounds the nostrils.

Possibly the black pigmentation in on the bill is missing revealing underlying colour.

Normal male Long-tailed Duck bills: Variation in the amount and shape of pink on bills of three adult male Long-tailed Ducks. 28 February 2010. Cherry Street and Humber Bay East in Toronto.