Hairy Woodpecker in the Fog

Emily Stone

Perpetual twilight cloaked the forest on the darkest day of the year. Even at noon, fog hung densely between us and the sun. Cabin fever had set in, and we felt like banging our heads against a wall. Trying to make the best of it, we layered up and ventured out onto the Superior Hiking Trail. The elegant forms of birch, aspen, oak, and balsam fir near the trail stood out against a plain background. Beyond them, only the gray mist met our eyes. Nothing moved in the oppressive dampness, save us and the assortment of snow, sleet, and rain drops that pelted the world.

Then a bird swooped through the edge of our vision, and a tapping sound punctuated the constant hiss of sleet. High on the trunk of a dying birch, a black-and-white-checkered woodpecker foraged in the bark crevices. His feathers blended perfectly with the white bark and black gnarls. A substantial, chisel-like beak – as long as the profile of his head – was evidently the perfect tool for prying and pecking bark beetle larvae from out of the punky wood. While leaning back for a better look, or perhaps winding up for a swing at the tree, his stiff tail provided a kickstand for support. The small patch of red feathers on the back of his head was a welcome bit of color in the gray woods, and it also informed me of his proper pronoun.

We didn’t stop to watch this male hairy woodpecker, but I did mull over the state of his head as we hiked on. He’s obviously quite well adapted for his lifestyle, but how can that little bird bang his head against trees all day and not develop debilitating headaches?  Scientists have been studying this problem for years, and for good reason. If we could figure out how to engineer anti-shock mechanisms into rapid collisions so that they were less damaging, it would revolutionize the world of transportation safety.

In the case of the woodpecker, scientists in China used CT scans and computer models to discover that the impact energy is converted to strain energy, and 99.7% of the strain energy is dissipated throughout the woodpecker’s body. The 0.3% of the strain energy that affects the head is converted to heat energy. This could cause the woodpecker’s brain to overheat and result in a different kind of damage, which is why woodpeckers take frequent breaks while they are pecking. It isn’t just about perfecting a rhythm or grabbing a bug, they are protecting their brain.

My psyche could use similar protection from the strain brought on by soupy weather and cabin fever! Instead of taking out our frustration by punching the walls, we hiked faster into the sleet. As the strain dissipated as heat, our red cheeks brought a little more cheer into the fog. It will only get brighter from here. Happy Solstice!

For over 45 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! The current exhibit, “Nature’s Superheroes—Adventures with Adaptations,” opens in May 2014 and will remain open until March 2015.

Find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Discover us on Facebook, or at our blogspot, http://cablemuseumnaturalconnections.blogspot.com.

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