Probably pollen on their bills.
Sent from my iPod
On Aug 26, 2010, at 5:32 PM, Maeve Kim <[log in to unmask]> wrote:
> Hummingbirds are clearly preparing for their long journeys, often spending as long as two minutes at one feeder perch - very unlike their eat-and-run habits of earlier in the summer. The birds that I've identified as juveniles all have a great deal of white at the base of their bills, extending more than a third of the way along the bill. I don't see this in Sibley or the National Geographic bird guide. Has anyone else noticed white bills?
> Maeve Kim
> Jericho Center