Crossbills are one of our most specialized groups of birds, feeding almost exclusively on conifer seeds. These hardy, nomadic finches have evolved oddly-shaped bills that allow them to exploit a food source before it becomes available to most other birds. However, being so specialized and relying on a single primary source of food means that when that food is unavailable, they have to search far and wide to make ends meet.
North America has two species of crossbills – white-winged crossbills (Loxia leucoptera) and red crossbills (Loxia curvirostra). Both are widespread across boreal regions dominated by conifer trees, and populations extend south into mountainous areas, with red crossbills reaching as far south as Mexico. In the Northeast, the more slender-billed white-winged crossbill, which is more commonly observed, spends most of its time foraging on the relatively small cones of spruce, balsam fir, hemlock, and tamarack, while red crossbills are typically associated with large-coned white and red pines.
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