Red Crossbill -- Food Specialist

The Red Crossbill goes through life with its upper beak twisted in one direction and the lower beak in the other. With such a bizarre tool it can deftly extract pine seeds from an open cone. Other birds have to wait until the seeds fall. Since it has such a narrow food preference, and since the abundance of pine cones varies with the weather, crossbills cannot remain in one area as most birds do. They must wander, searching for areas where the pines have had a good year. Movements that take crossbills out of their usual range are called irruptions. When the pine cone crop fails in the far north, for example, crossbills may irrupt into southern states to feed and nest, then move to another area when the food again becomes limited.