Behavior.—The bird is but little known—surprisingly little, considering how large a bird it is. It is a forest dweller; it lives almost wholly within the canopy of the treetops; it is alert, furtive (almost) as a bear, rather silent in midsummer (the season when city dwellers ordinarily visit the northern forests); and it easily eludes observation. It is not strange then that, its gigantic operations remaining in evidence, the bird itself should in common thought have become a somewhat fabulous creature. Thoreau (1906) never saw it; and this is what he wrote of it in the Moosehead Lake journal under date of July 25, 1857: “Our path up the bank here led by a large dead white pine, in whose trunk near the ground were great square-cornered holes made by the woodpeckers. * * * They were seven or eight inches long by four wide and reached to the heart of the tree through an inch or more of sound wood, and looked like great mortise-holes whose corners had been somewhat worn and rounded by a loose tenon. The tree for some distance was quite honeycombed by them. It suggested woodpeckers on a larger scale than ours, as were the trees and the forest.”
To one who visits its haunts the presence of the pileated woodpecker is immediately made manifest by operations such in magnitude as to have astonished Thoreau. Dead Norway pines may be found, gaunt and bare, their bark split away in plates and lying heaped at the base, and living white pines—young trees, particularly—pierced to the core with deep pyramidal incisions. The freshly cut wood gleams clean, and turpentine in pellucid globules rims the cut and drips downward. Great boles of maples and basswoods stand, furrowed from broken top to base, the ground below littered with splinters, often half a hand’s breadth in extent. The cuts are roughly rectangular in outline. They may be 4, 5, or even 6 or 8 inches wide and are sunk deep into the heart of the tree. They may extend vertically for a few inches or for a foot or more. They may be aligned in vertical rows, and may run together in furrows of several feet in length. Crumbling stumps and moss-covered logs lying on the forest floor will often be found ripped and torn by the woodpecker’s beak.
It is, as has been said, a wary creature, and is not easily stalked. On one occasion, when I had successfully approached a male that was idling in the top of a gaunt chestnut near the nesting tree, I paused, before shifting from an uncomfortable position, until the bird should sidle around the limb. Even so, he was quicker than I; for, before I had completed my movement, he was peering from the opposite side, and, detecting me, was off. Again I came upon a bird—a male—suddenly, in open forest. He did not immediately take wing, but, hitching downward upon the tree trunk, he reached the ground, hopped off, and then flitted away through the undergrowth, so that I scarcely saw him go. And when I came upon him again he repeated the maneuver.
With all their alertness, the birds have a large store of curiosity. Dr. Sutton (1930) has remarked that some individuals will “fly up hastily and boldly upon hearing a commotion in the woods.” They may sometimes be called up by imitating their cry, by clapping together the cupped palms of one’s hands, or by pounding with a billet of wood upon a tree trunk. I was following one morning a forest trail, where I knew a pair of the woodpeckers to be in residence, and had a glimpse, as I walked, of a large bird flying away. There stood against the sky, in the direction of the retreat, the stub of a great treetop. Pausing in my tracks, I waited until, after a few minutes, the suspected woodpecker came leaping up the stub—to have a look at me, as I supposed. In such case, the square shoulders of the bird, the slender white-striped neck, and the hammer head with its pointed scarlet crest are very conspicuous.
Maurice Brooks (1934) has remarked upon the playfulness of the birds when at ease.
For all their alertness, it remains still to be said that on occasion, when the birds are feeding, or when tending a nestful of young, it is possible to approach quietly and to remain watching, while they, unheeding, continue their activities.
It is common to find hairy and downy woodpeckers associated with the pileated, both on nesting grounds and when feeding. There is here, I believe, some measure of commensalism. I have in mind an observation upon a downy on the same dead hemlock tree with a pileated woodpecker. The larger bird was scaling off the bark and feeding; the smaller seemed to be gleaning over areas the pileated had left.
Tucked in the niche formed by a great furrowlike incision in the bole of a basswood tree, and about 10 feet from the ground, I once found a nest of the olive-backed thrush.
When I cut down the stub of which I have spoken, and which contained four old nesting cavities of the pileated woodpecker, I found the lowest, 25 feet from the ground, to be occupied by a family of white-footed mice (Peromyscus maniculatus), and I have no doubt that these cavities, after their abandonment by the woodpeckers, are commonly used by flying squirrels, by owls, and by tree-nesting ducks.
Prof. Brooks (1934) has most engagingly described the enticement of pileated woodpeckers to come to feeding trays, and, incidentally, has adduced evidence of their traits of caution and of curiosity. To this he adds (MS.): “I have indicated, in an article in Bird-Lore, that we have found Pileated Woodpeckers something of clowns. The gourd experience described in the above-mentioned article seemed to be in a spirit of play. The evident curiosity displayed by many birds observed is noteworthy; under its urge they apparently lose much of their fear. Around our blinds they have used a slow and cautious approach, but once at the feeding shelves, they have not been particularly nervous or excitable. At times I have found them surprisingly tame in the open woods.”