The Ultimate NOMADS

RANDOM MIGRATIONS ARE JUST ONE CROSSBILL QUIRK LEARN MORE FUN ODDITIES OF THESE WANDERING SPECIES.

KENN AND KIMBERLY KAUFMAN

Walking into a pine grove, you hear soft, unfamiliar calls overhead. Looking up, you see a dozen small birds clambering about over the pine cones, acting like tiny parrots. Some are red, some are dull yellow-green. Take a good look: These are crossbills, and they may stay put for a month or maybe a hundred miles away tomorrow. Two species, red crossbill and white-winged crossbill, are widespread in North America. And they’re among the most unusual birds in the world.

UNIQUE BEAKS

When you look at a crossbill’s face, it’s obvious how it got its name. The bill is thick at the base, but the mandibles cross over each other instead of meeting at their narrow tips. This shape would be awkward for picking up most items, but it’s perfect for one thing—prying open the cones of pines, spruces, hemlocks and other evergreens.

For most small birds, getting seeds out of a cone is too complicated to be worth the effort. For crossbills, it’s a snap. The bird inserts its bill between two cone scales and then closes it so that the crossed tips push the scales apart. Twisting its head, the bird works to reach the seed buried between the scales. Using its tongue against grooves on the inside of its bill, it pulls out the seed, cracks the dry husk and swallows the kernel. This happens in a lot less time than it takes to describe it—a crossbill can extract and eat more than 20 seeds per minute, which means better than one every three seconds!