The white-winged common crossbill ordinarily does not migrate. It is quite content in the Canadian provinces and the northern Great Lakes. However, it will head down as far as North Carolina for food, if necessary.
The white-winged crossbill, 6 to 6 inches long, is the size of a house sparrow. The mandibles are crossed. Those are the upper and lower parts of the bill. I personally am sometimes challenged to see those well. It looks like the bird is deformed with the upper mandible crossing the lower one and extending further from the forehead. The white wing bars contrast nicely with the black wings. The body of the male is pale pink. The female is olive gray with a little yellow on the rump. In a flock of crossbills, those white bars make it easy to spot them.
Like the redpoll, it is hunting for seeds of the evergreen trees. It favors hemlock and larch trees inland and pitch and black pines on the east coast. It likes eating seeds from cones that have dropped on the ground. One source noted seeing it at, Allegany State Park in January 1960. It had been a bad year for coniferous tree seed crops up north.
If those seeds aren't handy, it would eat seeds of deciduous trees, grass and other plants, fewer berries and very few insects. Because of its extreme fondness of salt, let this be a word to the wise. Watch out for the birds which are eating gravel and salt on the side of the road. It would make you feel horrible if you killed any bird.
At breeding season, the male white-winged crossbill will call while he slowly circles over a female. This event takes place from late winter to early spring.
Location, location, location. Informed folks know that some birds like to build a nest near the trunk of a tree. Others prefer the end of a branch. The white-billed crossbill is in the latter category. My sources show that it is not known if the male or female builds the nest. Here's a project for all of you birders. Which gender builds the nest?
We do know that the nest composition is of twigs, moss, lichen, grass, vegetation stems and tree bark. In addition, insect cocoons are added to the mix. Very fine materials are then arranged to add a soft lining.
Incubating the eggs is the female's duty. The eggs are light blue or green with brown and purple marks. They are about eight tenths of an inch long. The male feeds her during this time. He usually calls to her before delivering the food. Sometimes, he performs a flight song display.
The young are fed a regurgitated, milky seed pulp. Ugh. To each his own said the lady who kissed the cow.
In the winter, this bird travels in flocks of 12 to 50. A spectacular sighting would be of 300 birds. It will join red crossbills, redpolls, pine siskins, pine and evening grosbeaks, and waxwings.
Speaking of the red crossbill, let's learn a little about it. It's about the same size of the white-winged crossbill. The male might be a little more reddish than the pinkish male white-winged crossbill. The obvious difference is its lack of white on the black wings.
Nesting habits are the same as those of the first bird discussed, but it is known that the female selects the site for the nest. The eggs of the two species are the same color.
Its range doesn't go as far north in Canada as that of the white-winged. However, it will head for the hills of western Virginia and North Carolina and even Mexico. Interestingly, it usually has one brood, but in the Rockies, it might have two.
The bird is not born with crossed mandibles. They gradually form that arrangement gradually a few weeks after fledging. They are inserted into a cone to hold it open. Then, the tongue lifts out the seeds.
Both the white-billed and red-billed crossbills are uncommon this far south. Again, the seeds must be scarce farther north, so that they irrupt to our area.
Save the natural habitat. These birds are just another reason to do that.