How a Pileated Woodpecker Works

Pamelia photographed this majestic pileated woodpecker (a male—see the red cheek patch?) jack-hammering a tree 20 times a second, his bill pounding the wood at a head-rattling 15 mph, his eyelid closing...sideways?

 Photo by Pamelia Markwood

Photo by Pamelia Markwood

Photo by Pamelia Markwood

Yup. Woodpeckers (and some other birds, reptiles and sharks) have not only upper and lower eyelids but also a thick inner eyelid called the "nictitating membrane" that's clear or translucent and closes horizontally. It lubricates the eyeball without blocking the bird's vision (especially important during flight) and helps hold the eyeball in place when the woodpecker pummels a tree. "Nictitating" comes from a Latin word meaning "blink."

Photo by Pamelia Markwood

The huge, nearly crow-size, pileated (you can say PILL-ee-ated or PIE-lee-ated; the word means "crested") is a thrill to see or hear, as many of you know; its loud "wuk-wuk-wuk-wuk" call sounds like something from the jungle. But its anatomy is even more amazing. To handle the force of up to 12,000 tree pecks a day, the pileated has evolved extra-dense neck muscles, a compressible skull bone and a brain that doesn't slosh around in cerebral spinal fluid in its head (as human brains do, causing concussions and worse during skull impacts). Pileateds have virtually none of that fluid in their heads.

Photo by Pamelia Markwood

Notice in Pamelia's photos how the pileated uses its powerful four-toed talons and its long tail for grip and balance when pounding away. Her picture of the woodpecker pausing to scratch his head shows how wide the talons can spread. Two toes can point forward and two backward for extra bark-gripping strength. "I felt privileged to be able to watch him for an hour working on the tree," says Pamelia. "I was filled with joy to have experienced such a rare, rich, priceless moment."

Photo by Pamelia MarkwoodPhoto by Pamelia Markwood

Photo by Pamelia Markwood

Photo by Pamelia Markwood

Photo by Pamelia Markwood

Photo by Pamelia Markwood

One more clue (besides the male's red check patch) if you're trying to identify male or female: The red crest on the female goes only two-thirds of the way forward on the crown of her head, not all the way to the bill, as it does on a male. Wuk-wuk-wuk-wuk! Happy woodpecker-watching! —Craig Neff and Pamelia Markwood