V. A. Alderson (1890) published the following interesting note: “Last summer, potato bugs covered every patch of potatoes in Marathon County, (being my home county,) Wis. One of my friends here, found his patch an exception, and therefore took pains to find the reason, and observed a hairy woodpecker, making frequent visits to the potato field and going from there to a large pine stub a little distance away.
“After observing this for about six weeks, he made a visit to the pine stub and found, on inspection, a large hole in its side about fifteen feet up. He took his axe and cut down the stub, split it open, and found inside, over two bushels of bugs. All had their heads off and bodies intact.”
The woodpecker’s method of locating tree-boring larvae and its specialized apparatus for extracting them are so well described by Dr. Thomas S. Roberts (1932) that I cannot do better than to quote him, as follows:
The hairy woodpecker possesses in its tongue one of the most remarkably developed and perfectly adapted instruments for extracting the tree larvae from their tunnels. The tip is a rigid, barbed spear and can be thrust out to an astonishing distance by reason of greatly elongated, posterior horns which pass up over the back and top of the head and run together down in front of the right eye, around which they are coiled for almost the entire circumference of the socket! So that, the drilling into the tunnel accomplished, the tongue darts out, the inner ends uncoil, the spear transfixes the grub, and with little ado the larva is dragged from its retreat into the bill of the bird, pounded perhaps for a moment or two, swallowed forthwith or carried to the young, and this most perfectly contrived and highly efficient engine is once more ready for action. There has been considerable discussion as to how the woodpeckers locate the larvae, active or dormant, which are hidden deeply in the wood and for which they drill so unerringly. All the special senses of birds are very highly developed, and it seems probable that in this case hearing, touch, and smell all may play a part. The active grub, as it crunches the wood, makes a sound that would surely be audible to a bird with its keen sense of hearing. The tunnel produces a cavity which would give both a different sound and feeling on tapping over it. Such things as grubs have a strong odor, and it is probable that this plays a part also.
Forbush (1927) says: “Maurice Thompson asserts that the hairy woodpecker strikes its bill into the wood and then holds the point of one mandible for a moment in the dent thus made. He believes that the vibrations produced by the insect in the wood are then conveyed through the beak and skull of the bird to its brain.”
In winter this woodpecker comes readily to suet or meat bones hung up on our trees or feeding stations to attract birds. It is also said to feed on the carcasses of animals left in the woods by trappers or hunters and to pick the fat from fresh skins that the trapper has hung up to dry. Although often called a sapsucker, there is practically no evidence that it ever does any injury to trees in this way; any sap or cambium eaten is probably taken incidentally in its search for insects.
Behavior.—The hairy woodpecker is a much shier, more retiring bird than the confiding little downy; it is also more active and noisier; it usually will not allow such close approach but will dodge around the trunk of a tree or fly away, if an intruder comes too near, bounding through the air in a series of graceful dips and rebounds. Rex Brasher (1926) followed one for four hours that alighted “on two hundred and eighteen different trees, an average of nearly one a minute! The longest time he remained on one tree was seven minutes. This was a dead chestnut with most of the bark still adhering. By far the larger proportion of the trees were old chestnuts, and under their loosely attached covering he found most successful hunting. Rough-bark species were preferred—chestnuts, oaks, old maples and hickories, about in the order named. Smooth-barked ones received little notice.”
Dr. Morris Gibbs (1902) says: “Have my readers carefully watched a Woodpecker leave its perch on the trunk or limb? The bird throws itself backward from its vertical position by a leg spring, together with a tail movement, turns in the air in the fraction of a second and is sweeping away to the next perch. Arriving at the next resting place it makes a single counteracting stroke of the wings against the air, and perches lightly on the bark of limb or trunk.”
Like all woodpeckers, the hairy is an expert climber, perfectly at home on the trunk of a tree, or even on the under side of a branch, where its strong claws enable it to cling in almost any position or to move about with astonishing rapidity and skill in any direction. Its stiff tail feathers act as a prop and help to support it while hammering away at the bark with its powerful beak. Forbush (1927) says that it “is the embodiment of sturdy energy and persistent industry. Active, cheerful, ever busy, its life of arduous toil brings but one reward, a liberal sustenance. It sometimes spends nearly an hour of hard labor in digging out a single borer, but commonly reaches the object of its quest in much less time.”
Voice.—The ordinary call of the hairy woodpecker is louder and shriller than that of the downy. Francis H. Allen says, in his notes, that it bears “about the same relation to it as the solitary sandpiper’s peet-weet does to that of the spotted sandpiper. I hear it most frequently from the female. In fact, a female of the species that visits my place at all times of the year often utters this note continually, as if calling for a mate or claiming territory, but she never nests very near.”