The Common Redpoll is a species of finch that breeds in high tundra habitat. During the winter many birds head south, sometimes in great numbers depending on natural food supplies. When redpolls head south in large numbers (sometimes along with other so-called "winter finches"), it is known as an irruption.
Common Redpolls are found in suitable habitat across the northern half of North America, and across northern parts of Eurasia. Common Redpolls are social and tend to travel in large, gregarious groups. These birds of the north are know to be able to survive temperatures as low as -65F - sometimes by tunneling under snowbanks to stay warm!
"Red poll" refers to the patch of red on the bird's crown. Common Redpolls are similar to Hoary Redpolls but they can be told apart by their darker plumge and slightly larger bill.