[Published in 1939: Smithsonian Institution United States National Museum Bulletin 174: 13-24]
The hairy woodpecker *** ranges throughout practically all the timbered regions in North America ***. In the region where I am most familiar with it, southern New England, it is not an abundant bird at any season, quite rare in summer and oftener seen in winter. It is essentially a retiring, forest-loving bird, being found with us in summer in the dry deciduous woods, or occasionally in rural districts in old orchards near the borders of wooded areas. In winter, it is given more to wandering into villages and towns, or may be seen even in the shade trees in larger cities.
I remember having found it only twice in swampy woods, but Dr. George M. Sutton (1928b), in his paper on the birds of Pymatuning Swamp, Crawford County, Pa., says: "The hairy woodpecker occurs only rarely in the higher deciduous woods outside the borders of Pymantuning during the nesting season, but it is abundant everywhere in the wooded Swamp, and in the restricted area, closely examined in 1922, was considered one of the most numerous species."
Courtship.--Francis H. Allen has sent me the following notes on this subject: "The courtship dance consists of a weaving motion of the head, as with the flicker, accompanied by a high-pitched ch'weech, ch'weech, ch'weech, repeated over and over vociferously. The note is much like that of the flicker, but higher pitched and more rapidly delivered. Three and sometimes four birds may be seen so engaged together, but I have no observation as to the sexes. In quiet intervals in courtship, the head is held with bill parallel with the axis of the body, not at right angles as in feeding."
Edward H. Forbush (1927) writes:
On bright March days this bird begins to practise what is either a love song, a challenge, a call to its mate, or all combined. This is no vocal music but instead a loud drumming on some resonant dead tree, branch, or pole. This long roll or tattoo is louder than that of the downy woodpecker, not quite so long, and with a slightly greater interval between each succeeding stroke. It takes a practiced ear, however, to distinguish between the drumming of these two species. In courtship the male chases the female from tree to tree with coaxing calls, and there is much dodging about among the branches and bowing to each other before the union is consummated.
Rex Brasher (1926) writes:
Seated under a cluster of small maples, one day in early May, I watched the interesting courting antics of the pair. The jaunty male's favorite position was one in which he appeared to be almost standing on his tail. With bill upright, wings thrown forward, and tail wide-spread he repeated over and over what was undoubtedly intended for a love-song, a series of notes divided between chuckles and whistles. But the strangest, most mystifying performance was a series of backward drops on the under side of a limb inclined about forty-five degrees. . . . Why didn't the little acrobat fall when he released his claws? Studying his movements carefully through the binoculars, I came to the conclusion that at the instant of releasing his grip he jerked his body toward the limb with sufficient impetus to catch the bark six inches or so below.
Lewis O. Shelley says in his notes: "I have watched the act of copulation of the hairy woodpecker and noted its dissimilarity to the downy. For the hairy invariably instills a follow-up procedure to the display, the male coming to her call and, soon thereafter, hopping up the branch toward her with a short jerking movement, in which he calls wick-up, wick-up, wick-up, wings agitating, this immediately followed by copulation."
Nesting.--The hairy woodpecker is rather rare, as a breeding bird, in my home territory of southeastern Massachusetts, but I have the records of 12 local nests. It shows a decided preference for deciduous woodlands, six of the nests being in dry, upland woods and two in maple swamps; of the other four nests, three were in apple orchards, close to extensive wood lots, and the fourth was in a small, living, red maple in a swampy meadow, some distance from any woods. The birds showed no decided preference for any one species of tree; three nests each were found in maples and apple trees, two each in chestnuts and poplars, and one each in a dead oak and a dead beech. Only four nests were in dead trees or dead branches; the others were all in living hardwoods. The heights from the ground varied from 5 feet in a dead poplar stub to 30 feet, or more, in tall chestnuts or maples. The entrance to the nesting cavity often appears nearly, or quite, circular, but on careful measurement will usually be shown to be more or less elliptical, higher than broad; a typical entrance hole that I measured was 1 7/8 high by 1 1/2 inches wide. The depth of the cavity was found to vary from 10 to 12 inches, but Mr. Shelley (1933) measured one that was 15 inches deep, and even deeper holes have been reported. Owen Durfee's notes give some very careful measurements of two of our local nests, one of which is worth quoting as showing an unusually elliptical entrance: "The entrance to the nest was on the northeast side of the trunk of a live chestnut and 22 1/2 feet from the ground. The tree leaned toward the east about 2 feet. At the butt it was 9 inches in diameter and at the opening about 6 1/2 inches. The opening had the usual elongated appearance, 2 5/8 high by 1 7/8 inches wide. The top of the hole went straight in across the the cavity for 4 1/2 inches, the bottom edge of the opening slanting up 3/4 of an inch while going in 1 1/2 inches. Then the cavity went nearly straight down below the hole for 12 inches, enlarging only a trifle, so that the base was about 4 1/2 inches in diameter. The shell of the tree was only about 7/8 inch thick on one side but on the other was 2 inches thick."
Dr. Sutton (1928b) says of the nests in Pymantuning Swamp, Pa.: "The cavities were drilled near the tops of dead trees which nearly always stood in water. It was impossible to climb many of them because their bases were weak; but the clamoring of the young birds could be heard some distance away. On May 30, 1922, I located six nests within a half hour by watching the parent birds and listening for the young. . . . The twenty-six nests averaged roughly over thirty feet from the ground."
T. E. McMullen mentions in his notes a Pennsylvania nest that was 50 feet from the ground in a large maple in some woods. J. Claire Wood (1905) reports some very high nests in Michigan; one was in the "trunk of a very large barkless dead elm about 50 feet above ground"; another was in the trunk of a "dead beech 55 feet up and just under a large limb."
The female probably selects the nesting site, but both sexes work alternately at the labor of excavating the cavity. This work requires one to three weeks, depending on how hard the wood is; a cavity in the soft wood of a poplar, which is a favorite with this species in some localities, might be excavated in a very short time, but I have known a pair to take over three weeks to excavate a nest in a hard maple; the trunk of a living tree may have a soft center, and some of the birds seem to be clever enough to select such a tree. A new nest may often be recognized by the presence of fresh chips on the ground around the tree, as the birds are not very particular about removing them.
The male sometimes digs out another shallower hole near the nesting tree, which he uses as a sleeping place. Usually a fresh hole is made each season, but I have seen occupied holes that were very much weathered, as if they had been occupied for more than one season; in such cases, the cavity may be deepened somewhat and the bottom covered with fresh chips. I once found a pair of these woodpeckers excavating their domicile, which they later abandoned, as I found on a later visit that the hole was partly full of water and sap. They are not always successful in their first attempt, for this and other reasons, and may have to start two or three holes before they find just the conditions they want. The eggs are laid on a soft bed of fresh chips at the bottom of the cavity and are usually half buried in it; no nesting material is carried in.
Eggs.--The hairy woodpecker lays three to six eggs, but four seems to be the commonest number. The eggs vary in shape from oval to elliptical-oval, usually more nearly oval. The shell is smooth and often quite glossy. The color is pure white, but in fresh eggs the yolk shows through the translucent shell, giving the egg a beautiful orange-pink color.
The measurements of 47 eggs average 23.81 by 18.04 millimeters; the eggs showing the four extremes measure 29.50 by 18.80, 28.70 by 18.90, and 20.57 by 16.26 millimeters.
Young.--Only one brood is raised in a season, but if the nest is robbed, the female will lay a second set after an interval of 12 or 14 days, and sometimes even a third set; often subsequent layings may be in the same nest hole.
Bendire (1895) says:
The duties of incubation are divided between the sexes and last about two weeks. The young when first hatched are repulsive looking creatures, blind and naked, with enormously large heads, and ugly protuberances at the base of the bill, resembling a reptile more than a bird. They are totally helpless for some days, and can not stand; but they soon learn to climb. They are fed by the parents by regurgitation of their food, which is the usual way in which the young of most Woodpeckers are fed when first hatched. . . . the young remain in the nest about three weeks. When disturbed they utter a low, purring noise, which reminds me somewhat of that made by bees when swarming, and when a little older they utter a soft "puirr, puirr." Even after leaving the nest they are assiduously cared for by both parents for several weeks, until able to provide for themselves.
Plumages.--The young hairy, like all other young woodpeckers, is hatched naked, and the juvenal plumage is assumed while in the nest, so that when the young birds emerge they are fully fledged. In the juvenal plumage the sexes are sometimes much alike, though oftener there is a decided difference. In both sexes the bill is decidedly smaller, weaker, and more pointed than in the adult; the color pattern is almost exactly like that of the adult, but the plumage is softer and fluffier; the white markings are more or less tinged with yellowish, the two inner primaries are dwarfed, and the innermost white tail feather is usually tipped with black. The colored markings in the crown of both sexes are very variable in color and in extent. L. L. Snyder (1923) has made a careful study of the crown markings of young hairy and downy woodpeckers of both sexes. He found that 90 percent of the young male hairies had more or less red, pinkish, or yellowish markings in the crowns, and only about 14 percent of the young females were so marked. But only 10 percent of the young males and about 43 percent of the young females had white markings only on a black crown; and about 43 percent of the young females had the entire crown black. There is great individual variation in the amount and in the distribution of these colors; the white spots are often mixed with the other colors; the reddish and yellowish colors may invade nearly the whole crown, exist in one or two large patches, or appear on only a few scattered feathers.
The juvenal plumage is worn but a short time; the molt into the first winter plumage is accomplished between July and October. This first winter plumage is much like that of the adult in both sexes, but the white spots are not quite so pure white, and the red nuchal patch of the male is duller and often interrupted. Adults have a complete postnuptial molt in August and September and perhaps a partial prenuptial molt in spring.
Food.--Various studies of the food habits of the hairy woodpeckers show that these birds are among our most useful birds and especially valuable as protectors of our forest and shade trees and orchards. More than 75 percent of their food consists of injurious insects, while the amount of useful insects and cultivated fruits that they destroy is insignificant. Prof. F. E. L. Beal (1911) has published the most exhaustive report on this subject, based on the study of 382 stomachs collected during every month in the year and from many parts of the range of the species, including practically all of the races. He says: "In the first analysis the food divides into 77.67 percent of animal matter and 22.33 of vegetable. The animal food consists of insects, with a few spiders and millepeds; the vegetable part is made up of fruit, seeds, and a number of miscellaneous substances." Of the animal food, he says: "the largest item in the annual diet of the hairy woodpecker consists of the larvae of cerambycid and buprestid beetles, with a few lucanids and perhaps some other wood borers. These insects constitute over 31 percent of the food and are eaten in every month of the year. . . . One stomach contained 100 of these larvae and 83 and 50, respectively, were taken from two others. Of the 382 stomachs, 204, or 53 percent, contained these grubs, and 27 of them held no other food. Other beetles amount to a little more than 9 percent."
Ants rank second in importance, amounting to a little more than 17 percent, and are taken every month in the year; other Hymenoptera are eaten in very small quantities and irregularly. Caterpillars are the next most important item, many of them wood-boring species, amounting to a little less than 10 percent. "Prof. F. M. Webster states that he has seen a hairy woodpecker successfully peck a hole through the parchment-like covering of the cocoon of a Crecopia moth and devour the contents. On examining more than 20 cocoons in a grove of box elders, he found only 2 uninjured," according to Professor Beal (1911), who adds that bugs (Hemiptera) and plant lice (aphids) form only a small part of the food, and says: "Orthoptera, that is, grasshoppers, crickets, and cockroaches, are rarely eaten by the hairy. A few eggs, probably those of tree crickets, and the egg cases (ootheca) of cockroaches, constitute the bulk of this food. These with a few miscellaneous insects amount to a little more than 2 percent for the year. Spiders with their cocoons of eggs, including one jointed spider (Solpugidae), and a few millepeds, were eaten to the extent of about 3.5 percent, which completes the quota of animal food."
He says further:
The vegetable food of the hairy woodpecker may be considered under four heads: Fruit, grain, seeds, and miscellaneous vegetable substances. Fruit amounts to 5.22 percent of the food, and was contained in 54 stomachs, of which 13 held what was diagnosed as domestic varieties, and 41 contained wild species. Rubus seeds (blackberries or raspberries) were identified in 4 stomachs, and were counted as domestic fruit, but it is perhaps more probable that they were wild. . . . Of wild fruit 18 species were identified. It constitutes the great bulk of the fruit eaten, and is nearly all of varieties not useful to man.
Corn was the only grain discovered in the food. It was found in 10 stomachs, and amounted to 1.37 percent. . . . The seed of poison ivy and poison sumac (Rhus radicans and R. vernix) were found in 17 stomachs, and as they usually pass through the alimentary canal uninjured, the birds do some harm by scattering the seeds of these noxious plants. . . . Cambium, or the inner bark of trees, was identified in 23 stomachs. Evidently the hairy does but little damage by denuding trees of their bark. Mast, made up of acorns, hazelnuts, and beechnuts, was found in 50 stomachs. It was mostly taken in the fall and winter months, and appears to be quite a favorite food during the cooler part of the year.
Illustrating the quantities of insects eaten by individual birds, F. H. King (1883), Wisconsin, writes: "Of twenty-one specimens examined, eleven had eaten fifty-two wood-boring larvae; five, thirteen geometrid caterpillars; ten, one hundred and five ants; six, ten beetles; two, two cockroaches; two, nine ootheca of cockroaches; two, two moths; one, a small snail; one, green corn; one, a wild cherry; and one, red elderberries. . . . One of the above birds had in its stomach eleven wood-boring larvae (Lamides?) and twelve geometers; another, thirteen larvae of long-horn beetles and four cockroach ootheca; another, nine wood-boring larvae; and two others together had three wood-boring larvae, and nine larvae not coleopterous."
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 retracting 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 larvae 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."
Bendire (1895) describes its ordinary note as "a shrill, rattling note, triii, triii"; and again as several loud notes uttered on the wing, like huip, huip. Forbush (1927) calls the ordinary note "a high, sharp, rather metallic chink or click." Aretas A. Saunders (1929) says: "The call is a loud 'keep,' like that of the downy woodpecker, but louder. Another call is a loud rattle, suggesting that of the Kingfisher, but slurring down the scale. Another call, 'kuweek kuweek kuweek kuweek,' is used during the mating season, and suggests the Flicker's 'oweeka.' "
Field marks.--The hairy woodpecker is a large edition of the downy woodpecker, a black and white woodpecker, white below and black above, spotted with white on the wings, and with a broad white stripe down the center of the back. Only the male has the red patch on the back of the neck. It can be distinguished from the downy by its much larger size, its more restless behavior, its relatively longer and larger bill, and by the lateral tail feathers, which are pure white in the hairy and somewhat barred with black in the downy.
Enemies.--B. T. Gault, in his notes from Marshall County, Ill., states: "The hairy woodpecker is now a very rare breeder here owing to the fact that the English sparrow appropriates almost every nest hole as soon as it is excavated. I once saw one of these sparrows enter the hole of one of these birds, take a newly hatched bird out in its bill, flutter for an instant over the water (the nest was in a dead willow snag standing in the overflowed Illinois River bottoms), and drop the young bird into the water to drown. It then returned into the nest and soon appeared with another newly hatched woodpecker in its bill. As it fluttered over the water for an instant, my gun cracked and the sparrow died."
Verdi Burtch (1923) writes: "April 16, 1922, when in a thin wood I heard a female hairy woodpecker making a great fuss as they do when one invades the vicinity of their nest. As I neared the place I saw the nest hole about twenty feet up in an elm stub. About ten feet away, sitting erect on a limb of another tree, was a red squirrel eating something that it held in its fore-paws. My 8 power binoculars showed this to be a naked baby bird, presumably a hairy woodpecker and not more than two or three days old."
Mr. Shelley (1933) tells of a pair of hairy woodpeckers that were twice, in the same season, driven out of their nest by starlings and their eggs destroyed.
Fall.--The hairy woodpecker has often been said to be a permanent resident on its breeding grounds, but this is not strictly true. The species may be present all through the year over much of its range, but there is evidence to indicate a general southward movement in fall; the individuals seen in winter are probably not the same as those seen in summer. Moreover, there is a noticeable increase in numbers in certain localities in winter.
Lewis O. Shelley has sent me some full notes on the migration of hairy woodpeckers, as he has observed it near East Westmoreland, N. H., from which I quote as follows: "For four years I have watched, in the autumn months, passing hairies that go through some dropping down into the valley to feed as they go along, but others passing over the valley from hill to hill (2 miles) without stopping. In passing through, they traverse in general the same route each year. They come from an eastern and continue on in a western direction at an oblique angle to the Connecticut River, which they must cross in the vicinity of Brattleboro, Vt.
"These migrants usually appear here late in August or early in September and continue to arrive at irregular intervals until late in October. It is common for one, or two, rarely more, to pass together; but such occurrences have happened, as on October 24, 1934, when, beginning soon after noon and lasting until four o'clock, the birds continued to pass through. At least 12 were seen as I walked up a roadway parallel to their course; and other moving birds were heard. It was also noticed that they kept spaced 40 to 50 yards apart, keeping abreast of one another, traversing in a leisurely manner; and as they approached a rock maple woods, the tendency was to close in like passing through the neck of a bottle and, once through the woods, again to spread out. Their progress was rather fast; and they fed little, if at all. They often called, as though to locate each other, since they were keeping about 40 yards apart, as was easily noted when they crossed pasture and mowing land.
"I followed and watched in particular a male that continued keeping along ahead of me. He repeatedly crossed the road in a zigzag manner. Climbing to the top of a fence post or stump, he made lengthy observations, probably noting the progress of the other birds, and often answered their ringing calls. He, as well as the others, gave the appearance of a stranger in a new environment, truly a migrant. I noted how low the birds were passing, quite frequently flying not over 2 feet from the ground over open spaces, where long, bounding flights were made."
L. McI. Terrill told Mr. Forbush (1927) that the few local breeding birds disappear from the vicinity of Montreal early in autumn, and others, in a very noticeable wave, appear toward the end of October or early in November.
Winter.--Aside from the regular migratory movements, the hairy woodpecker is much more given to wandering about in winter. It is apt to forsake its woodland haunts and travel about in search of food, coming frequently into the farmer's orchard, into rural villages, and even into thickly settled communities in some of our larger cities. Here it often joins the merry parties at our winter feeding stations, feeding readily on the suet or scraps of meat provided for our insect-eating birds; and here the smaller birds show due respect for its larger size, or perhaps for its formidable beak, and it is usually allowed to eat alone. It seems to be a solitary bird at this season, for we seldom see more than one at a time. I find it not so constant and regular a visitor to my feeding station as the downy woodpecker and some other birds; it probably wanders about more.
Mr. Forbush (1927) writes: "During the inclement season it is said to require a sheltered place in which to sleep and, like the downy woodpecker, to excavate a hole in a tree for a sleeping chamber, but there is evidence that it does not always seek such shelter, as the late Charles E. Bailey and myself watched one for several winter evenings in a grove, clinging upright against a tree trunk in the usual woodpecker position. Night after night, the bird was there at dusk, remained there until dark, and was there also at daybreak each morning in precisely the same place."
Joseph J. Hickey tells me that, around the lower Hudson River
Valley in winter, woodpeckers obtain much of their food by
deliberately scaling the bark off trees in search for their insect
food. The Arctic three-toed woodpeckers work mainly on pines and
hemlocks, but the hairies appear to confine their work to the
hemlocks, using the same methods as the three-toed.
Hairy Woodpecker* Picoides villosus [Eastern Hairy Woodpecker]
*Original Source: Bent, Arthur Cleveland. 1939. Smithsonian Institution United States National Museum Bulletin 174: 13-24. United States Government Printing Office