Redpolls

It's been a good year for redpolls. Every few years there's an irruption of winter finches from Canada when their food resources are scarce up north.

 

I'm in Upstate New York, and here they hang out with the goldfinches. In fact, they’re related to goldfinches (in the sense that both are in the finch family). They’re about the same shape and size and they eat the same kinds of seeds, but there it ends. Redpolls resemble streaky sparrows with a red cap and black around the bill and the males have an added raspberry wash on the breast. Winter brings them to New York from northern Canada and this is about as far south as they normally need to go. These are tough little birds.

Although they seem perfectly at home in the bushes near our feeders, the redpoll’s natural preference is open fields and patches of weeds. They’re more likely to appear in alternate years or irregularly when seed production from spruce and birch trees across northern Canada and Alaska is reduced. Redpolls also eat the seeds of willows and alders. When they're on the snow under our feeders, they're picking up sunflower seeds dropped by the other birds.

To make it through long, cold nights, redpolls have evolved a version of the crop, a throat pouch (on the esophagus) where a supply of seeds can be stored. After finding a sheltered perch, usually in a conifer, and then fluffing up their dense feathers for added insulation, they slowly digest the stored seeds at their leisure. The combination of food and fluff maintains a core body temperature of 105º F. This allows redpolls to survive colder temperatures than other songbirds.

During the summer they are abundant in boreal forests and open tundra around the subarctic regions of both North America and Eurasia.

Ornithologists, the people who study birds, still can’t decide how many redpoll species exist. At the moment, there are two. The Common Redpoll, Carduelis flammea, is the bird normally seen at winter feeders and traveling in flocks across fields. The rarer Hoary Redpoll, Carduelis hornemanni, is generally lighter in color, giving it a "frosted" appearance, hence the name hoary. Due to individual variations, there is almost an overlap between the two types of redpolls, and some ornithologists believe there is just one species with a number of races. Perhaps DNA studies will help to sort this.

For a small finch that weighs less than an ounce, the redpoll has wonderful adaptations that allow it to survive the toughest winters, not to mention unpredictable summers in its far northern homeland. The next time you’re feeling cold, remember the bird that finds warmth in Upstate New York winters.

For an interactive range map of the Common Redpoll, visit the eBird website and zoom in to your location. Recent report locations (within the past 30 days) are coded red. You also can set a custom date range to find recent reports.

Corrections, questions and suggestions are always welcome at northeastnaturalist@yahoo.com or connect through my Facebook page and photo page. There is a separate community-type page for The Northeast Naturalist. Other nature and geology topics can be found on the parallel blogs Adirondack Naturalist and Heading Out.