Laura Erickson's For the Birds

This attractive little warbler breeds in the boreal forests of Canada and far northern New England. It’s lovely ringing song can reach a frequency of 10,000 Hz, beyond the hearing range of a great many people. A quick look can give the impression that in breeding plumage, this bird is entirely black and white, but the pronounced black and gray streaks on the upper back grade to a greenish wash on the lower back and edges of the flight feathers. The bill is tinged with bright yellow, and the bright yellow feet, important to distinguish fall Blackpolls from Bay-breasted Warblers, can stand out in breeding plumage as well.

Blackpoll Warblers winter east of the Andes in South America, arriving there from the East Coast via the longest overwater journey of any songbird—nearly 1,800 miles nonstop over the Atlantic Ocean. They’re obviously very sturdy for a half-ounce bird, but thanks to destruction of their boreal forest habitat, they are in steep decline.