Common redpolls, clockwise from left female, female, male and bottom is male again. First year male birds look very similar to females and can be hard to distinguish.
Redpolls like birch trees. When they hit the feeders en masse it feels like an invasion!
(Remember that you can double click on these images to see them larger)
These adorable, scrappy little birds are Common redpolls. Redpolls are a woodland bird of the northern tier of the United States, breeding in the taiga. They only come this far south in the winter. As a rule, less than 2 % of all the redpolls reported to Cornell Lab of Ornithology are reported this far south. I get a few every year, but this year I've been invaded by a spectacular riot of redpolls. Maine birders have been reporting unprecedented numbers.
This has been an irruptive year, that is the birds are busting south from their normal northerly range in search of food. The irruptions are a cyclic phenomenon. Redpolls eat tiny seeds. They have pouches in their throats that allow them to gather lots of food quickly, and then take off to a safe place with it. They eat mostly seeds of catkin bearing trees like birches and spruce seeds. When there is a crop failure of these seeds, the birds have to look elsewhere. At about latitude 44, our coastal Maine homestead is rich in high latitude spruce and birch trees .
Redpolls forage in flocks sometimes numbering in the hundreds. The flock that has been hanging around here for the past two weeks is about fifty strong. Constantly on the move, they descend from the sky in rolling waves. They are busy, finchy and acrobatic birds that are well adapted to feeding at the very tips of small branches, hanging upside-down, and using their feet to hold food. They also forage on the ground, especially in winter. I see them suddenly and then, just as suddenly, they are gone. Like a lot of finches, they have an undulating flight pattern. Slightly bigger than an American goldfinch, they could easily be mistaken for them in the sky. Though they seem so finch like, the redpolls closest bird relatives are the crossbills, another bird of the northern forests given to irruptions. Like the crossbills, I can usually hear the redpolls even before I see them. They are quite vocal, constantly making contact calls within the flock. The call is a dry reeling song like goldfinches with a rolling burr at the end.
Sometimes redpolls are in mixed flocks of goldfinches, winter sparrows, juncos and other small winter birds. Rare visitors to southern Maine are Hoary redpolls, though they have been reported near here this year, too. I have yet to see one, but I scour these flocks looking at every bird in the hopes of finding one. You'll be the first to know when I do! Depending on who you talk to, there are either one, two or six species of redpolls. This is because birders like to argue. Actually, it's because there are so many variations that without DNA samples, redpolls are hard to nail down. One of the species lives in Finland, so if I tell you I've seen one here, you'd better check my pulse and cut off my bar tab. The other two that are known to occur here are Common and Hoary. Hoarys are a little bigger with a smaller bill. They have a frosted look, thus the name "hoary," which is not a misspelling of slutty behavioral traits. I know what you were thinking! It can be tricky telling the difference between Commons and Hoarys because there are lots of variations. To anyone's knowledge, the two don't interbreed which would make them Common Hoars. Redpolls are named for the red knot on their heads. Males have pink or cherry red breasts depending on how old they are. Females just have the knot, or 'poll' on their heads. Red Poll cattle are named for the same thing, the red knot on their heads, but they don't fly. If they start falling out of trees like the redpolls have been, my advice is "don't look up and keep your mouth shut."
These are Red Polls, not redpolls. Though they can be tipped, let's hope they never fly.
Thanks to allboutbirds.com, wikipedia and the following for some of the information:
Sibley, David A 2000, The Sibley Guide To Birds. Knopf: New York (2000) p 532