Black Bird, Bright Bill

There was a discussion not long ago on one of the mailing lists about a “mystery bird” in a European park: all black, with an orange bill.

There’s no doubt that the puzzle bird was a male European Blackbird, one of the commonest birds of many landscapes in western Europe. At the time, I put the description of the bill color down to poor observation. But this latest trip to Vienna made me reconsider.

This male Blackbird, photographed in Vienna’s Donaupark last week, had a bill nearly red–and the orbital ring was just as deep and vivid. Astonishingly, this was just one of at least four such birds I saw over the course of our stay; “normal” birds of this species have yellow bills and orbital rings, and I’d never seen anything this bright before. Interestingly, the tarsi and toes, as readily visible here, were the standard dull gray-horn color, obviously unaffected by whatever factor had resulted in the hyper-pigmentation of the remaining soft parts.

Michael suggested that the culprit might be an immodest consumption of ornamental honeysuckles, but so far as I know, that has been implicated only in plumage variation, and should (shouldn’t it?) have affected the tarsi as well. I thought instead of the bright-billed (and bright-footed) Laughing Gulls one encounters in the eastern US, and recalled, too, the two orange-billed European Starlings hanging out at Sandy Hook this winter.

Who has a real answer?