The pileated (pie-lee-8-ed) woodpecker
I’m always impressed by the abundance and colorful variety of tropical birds. Magazines and television devote plenty of time to parrots and parakeets, toucans and birds of paradise, blue-footed boobies—we’ve seen them all, even though we’ll probably never see them in the wild. But right here at home, we have a large, colorful bird that surely a visitor from another part of the world would find quite as extraordinary as any from the tropics: the pileated (pie-lee-8-ed) woodpecker, Dryocopus pileatus.
“Pileated” means having a crest on top (“pileus” is also the scientific term for mushroom cap), and a brilliant red crest is one of the distinguishing characteristics of this magnificent 16 to 19-inch-long (crow-sized) bird. Its distinctive plumage is rounded out with striking black and white stripes on the head and neck and a black back.
Though uncommon (breeding pairs are usually at least a mile apart even in good habitat), the pileated woodpecker is at home in the old-growth—or mature second-growth—forests of eastern North America, Canada, and the mountain regions of the west. Nesting pairs have been reported in the northern lower peninsula (half a dozen in Cheboygan County), but the farther south in the state you go, the rarer these birds become.
Until the late 1800s, pileated woodpeckers were common throughout Michigan. The extensive lumbering and widespread forest fires that accompanied European settlement of the state drastically reduced their range. It has since been discovered that these birds require standing dead trees (called snags) and mature living trees (with dead branches) at least 8 inches in diameter for feeding, 18–26 inches in diameter and 39-69 feet tall for nesting.
Some years ago, foresters undertook a study of the effects of various forest management techniques on the habitat and the population of pileated woodpeckers in Jefferson National Forest in the Blue Ridge Mountains of Virginia. Eight areas undergoing different forestry management schemes were chosen for the study, along with one area that had been left untouched for comparison.
The first area had been cut 20-30 years earlier, using the “shelterwood system,” designed to achieve forest regeneration under the shelter of large overstory trees, which are subsequently removed. If the overstory trees were not harvested, this method might produce habitat for the birds. But if that were the case, the regenerating understory would not reach harvestable size.
Area two was a one-year-old clearcut and, not surprisingly, had no pileated woodpecker habitat. Neither did area three, a 16-year-old clearcut, nor did area 4, a six-year-old clearcut without reserves. Even area 5, a clearcut with reserves (that is, with some trees left standing), had no snags or large-diameter trees.
Area 6, which employed “understory control,” also had no dead trees, but some trees ranging from 8 to 13 inches in diameter suggested possible future habitat. Area 7, the “leave tree cut,” in which some trees are left to regenerate the forest, had the highest number of snags but few trees of sufficient diameter. Area 8 was “thinned,” had no snags and a variety of smaller diameter trees.
But guess what! Area 9, the plot that had been untouched, had the greatest variety of tree diameters, the greatest number of standing dead trees, and, of course, the best habitat for pileated woodpeckers.
Traditionally, foresters haven’t been able to bear letting good timber “go to waste” by allowing standing trees to die, but what is anathema to timber interests is exactly what the pileated woodpecker needs. D. pileatus feeds year-round on carpenter ants in large dead trees or tree limbs. In fact, the particular holes that they excavate, square-sided (rectangular) and as long as 6 feet and 6-8 inches deep, are the most obvious sign—in addition to the loud, intense hammering sound they produce—of the otherwise shy bird’s presence.
For many years, even scientists believed that pileated woodpeckers must have some kind of shock-absorbing structures in their head and neck to protect them from the forces they create with their intense pounding. While woodpeckers’ skulls do have spongy bone in the front, thick muscles in the neck, and a third inner eyelid to keep the eyeball in place, these adaptations do not reduce the forces at play in pecking. It turns out that the woodpecker’s very small brain size means that it does not move with enough force to create any kind of damage.
Courtship begins between January and March, and the pair digs a 10-28-inch deep nest cavity in a dead or partly rotten tree, usually at least 15 and up to 80 feet above the ground. The female typically lays four eggs, which are attended to constantly, with both parents taking turns on the nest. Like most birds, the young are completely helpless at first but mature rapidly, leaving the nest (though still dependent on their parents for food) after 24 days or so. They hang around until fall, then go off on their own to establish new territories.
The value of D. pileatus is more than aesthetic, though. It is now recognized as a major habitat creator whose excavations provide shelter for other animals and whose activities accelerate the return of the nutrients locked in dead trees to the soil.
It looks as though pileated woodpecker populations are on the rebound in Michigan as second-growth forests reach maturity in the northern parts of the state. And luckily, as the public increasingly sees the presence of nongame wildlife as part of any multi-use forest management regime, foresters have become more aware of what these magnificent birds do and require.n
