White-breasted Nuthatch | Life Histories of North American Birds | A.C. Bent
Feather Pic Arthur Cleveland Bent

Life Histories of Familiar North American Birds
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White-breasted Nuthatch
Sitta carolinensis

Contributed by Winsor Marrett Tyler
[Published in 1948: Smithsonian Institution United States National Museum Bulletin 195: 1-12]

The white-breasted nuthatch is a droll, earnest little bird, rather sedate and unemotional. He is no great musician and seems to lack a sense of humor. He has none of the irrepressible fidgetiness of the house wren, none of the charming happiness of the song sparrow; he appears to take life on a matter-of-fact level. He is short-necked, broad-shouldered, sturdy, quick and sure in his motions, suggesting an athlete, and as we study him on his daily round, as he hops up and down over the bark, we see that he is an athlete with marked skill as an acrobat, like the tumbling kind, as much at home upside down as right side up.

It is a characteristic pose of the nuthatch, perhaps unique among birds, to stand head downward on the trunk of a tree with the neck extended backward, the bill pointing straight outward from the bark.

Spring and Courtship.--If we have had a male nuthatch under our eye through the winter, either a bird roaming through a bit of woodland or one visiting our feeding station daily, we notice, as spring approaches, a change in his behavior: he begins to sing freely at all times of day, whereas previously he sang sparingly and only in the morning hours. At this time his deportment toward his mate changes also. All through the winter the pair has lived not far apart, feeding within hearing of each other, but the male has paid little attention to his mate; in fact, on the food shelf he has shown dominance over her; but now in the lengthening, warmer days of spring he becomes actively engaged over her comfort. A real courtship begins: he carries food to her and places it in her bill, he stores bits of nut in crevices of bark for her convenience, and he often addresses his singing directly to her. Standing back to her, he bows slowly downward as he sings, then in the interval before another song he straightens up, then bows as he sings again. The songs come with perfect regularity over and over again and can thus be recognized even in the distance as the courtship song.

We may imagine what a changing color scheme is presented to the female bird, if, as his song invites her to do, she glance his way--the black of his crown and his rough raised mane, then the blue-gray of his back, then the variegated black and white pattern of his expanded tail, then, perhaps, at the end of his bow, a flash of ruddy brown. At other times he approaches the female more aggressively, strutting before her with stretched-out neck and flattened crown, a pose of intimidation.

The change from the passive behavior of the winter months to active courtship takes place in New England early in April and indicates the advent of the nesting activities.

Nesting.--Speaking of eastern Massachusetts, William Brewster (1906) says: "The favorite breeding haunts of the White-bellied Nuthatch are ancient woods of oak, chestnut or maple where the trees are of the largest size and more or less gone to decay." In these surroundings the bird commonly builds its nest high up in a tall tree, either in a natural cavity or in an old woodpecker's hole, or, in an orchard, it may make use of a knothole in an apple tree.

Edward H. Forbush (1929) states that nuthatches sometimes nest in a cavity excavated by the birds themselves in decayed wood. Such instances, however, must be of rare occurrence, for William Brewster once told me that he had never known of a case.

Mr. Bent describes a nest "about 30 feet from the ground near the top of a large crooked swamp maple that stood near the end of a strip of woods on a private estate. The cavity was a rotted-out crevice in a nearly horizontal branch. The opening was too narrow for me to insert my small hand and had to be enlarged. The nesting material consisted of a small handful of soft fur that looked like rabbit fur, but nothing else; the cavity was very small and not over a foot deep."

Thomas D. Burleigh (1931) says of the bird in the mountainous regions of central Pennsylvania:

This species is one of the most characteristic birds of the scattered short stretches of woods in the open valleys, one pair at least, frequently two, being found in each one. Nesting is well under way by the middle of April, and by the latter part of that month or the first of May these birds are incubating full sets of from seven to nine eggs, the last being actually the commoner number. The nests are invariably in knot holes in the trunks of the larger trees, varying in height from 15 to 50 feet from the ground, the cavity itself being 6 to 8 inches in depth, and usually 6 inches from the entrance. The nests are substantial matted beds of soft shreds of inner bark and rabbits' fur, with rarely a little wool, cow hair, and chicken feathers. But one brood is raised each year.

Francis H. Allen says in his notes for April 18, 1942: "My attention was called by low-pitched notes of indeterminate character. I found a pair acting in a strange manner about a bird house on the side of a tree. Besides feeding or going through the motions of picking food from the bark, they spent much time in wiping the bill from side to side--that is, the right side and left side of the bill alternately in rapid succession over and over for a considerable period of time in each bout. It was like the swinging of a pendulum in its regularity. The male did most of this, but the female also took part. A courtship rite was suggested, though it was not accompanied by any form of display. It was so regular and so long continued that I do not think it could have been merely for the purpose of cleaning the bill, though it may have started in that way and have been continued by imitation and as a sort of play."

William Brewster (1936) writes thus of the birds nesting in Concord, Mass.:

There is a round hole about 3 1/2 inches in diameter 60 feet above the ground in our big elm, in which a pair of Flickers reared their brood 6 or 7 years ago. It has since been occupied at all seasons by gray squirrels. I have seen three animals enter and leave it within a week. Yet this morning about 8 o'clock a pair of White-bellied Nuthatches were building a nest there. The female did most of the work and performed it with remarkable rapidity. She would run out on a large branch, pry off a scale of bark 5 or 6 inches long, take it into the hole and almost instantly reappear and go after another. The male occasionally got one and simply poked it into the hole, without entering himself.

Of the several accounts in the literature of nuthatches breeding in bird boxes the following is an example, showing also the bird's method of obtaining rabbit fur for the lining of its nest. Lucien Harris (1927), of Atlanta, Ga., writes:

I saw a pair of White-breasted Nuthatches carrying strips of bark into the soap box. Often they would carry strips larger than themselves. They were very industrious and paid no attention to us. The birds used the bark to cover the entire floor of the box and the layer was about half an inch in thickness. They then proceeded to collect little pellets of dried earth and lumps of mud which were scattered thinly over the bark.

After this preliminary they started on the nest proper, which they placed in a back corner of the box. The nest was saucer-shaped and constructed of small twigs, grasses, and rootlets.

Then, as if not quite satisfied, this unique pair discovered a dead rabbit--one that had been dead for some time--and proceeded to line the nest proper, as well as the rest of the box, with rabbit fur, so that when completed the box smelled more like a buzzard's domicile than a nuthatch's home. Brer' Rabbit's fluffy tail held a conspicuous place in the middle of the box.

The habit of taking hair from dead animals may be the birds' usual procedure, for Edward H. Forbush (1929) says: "Mr. Maurice Broun tells me that he saw one come down from a tree and hop along the ground until it reached a dead squirrel from which it plucked a bunch of hair nearly as large as its own head."

Helen Granger Whittle (1926) gives a record of a pair mated for 2 years. She says: "In the Bulletin for October, 1925, I reported a pair of Nuthatches (Sitta c. carolinensis) which had remained together a winter and a summer, and which had brought a family of young to our Peterboro [New Hampshire] station in July 1925. These parents have been under observation for another year. They have now spent at least two winters and two summers constantly in each other's company, and they have raised two families which we know about. Keeping 'tabs' on these birds has been simplified by the fact that both are banded on the left tarsus. All our other Nuthatches have been banded on the right tarsus."

Eggs.--[AUTHOR'S NOTE: All the nuthatches lay large sets of eggs, and the white-breasted nuthatch is perhaps the most consistently prolific; it lays 5 to 9 or even 10 eggs to a set, but the extremes are uncommon; 8 seems to be the commonest number. In a series of 15 sets in the J. P. Norris collection there are 2 sets of 5, 1 of 6, 3 of 7, 7 of 8, and only 1 of 9.

The eggs are usually ovate or short-ovate and have very little gloss. The ground color is usually pure white but often creamy white and sometimes pinkish white. They are prettily and usually heavily marked with bright reddish brown, "ferruginous," "cinnamon-rufous," "hazel," or "vinaceous" and sometimes with a few spots of pale lavender or purplish drab. The markings are often thickest at the larger end; some eggs are even sprinkled over the whole surface with fine dots of pale brown.

The measurements of 40 eggs in the United States National Museum average 18.8 by 14.3 millimeters; the eggs showing the four extremes measure 19.8 by 15.0, 17.3 by 13.0, and 18.3 by 15.2 millimeters.]

Young.--The young birds when they leave the nest look very much like their parents. In Mr. Bent's nest there were "two females and three males, showing the same sex characters as the adults. They were nearly grown and fully fledged; they could not fly much, but could climb perfectly."

Dr. Arthur A. Allen 1929 states that the incubation period is 12 days and that both parents incubate the eggs and feed the young for 2 weeks after they have left the nest. He says that the young birds do not return to the cavity to sleep, but "cling upside down to the trunk of a tree beneath a projecting branch."

In Dr. Wilbur K. Butts's (1931) experience, "the male Nuthatch does not assist in incubation. He does feed the female while she is on the nest. . . . Both sexes feed the young."

Plumages.--[AUTHOR'S NOTE: All the nuthatches are peculiar in having a juvenal plumage that closely resembles the adult nuptial plumage and in which the sexes are distinguishable by the same characters as in the adult. In the young male the black of the pileum and hind neck is duller than in the adult and less sharply defined against the gray back, and the edges of the greater wing coverts are more or less gray. The young female is similar, except that the pileum (front half of the crown) is deep plumbeous-gray instead of black; the hind neck is dull black. Otherwise, young birds of both sexes are much like their parents.

Dr. Dwight (1900) says that the first winter plumage is "acquired by a partial postjuvenal molt, in July, in Florida, which involves the body plumage and wing coverts, but not the remiges nor rectrices, young birds and adults becoming practically indistinguishable."

Adults have a complete postnuptial molt in July.]

Food.--The nuthatch feeds on insects as well as on nuts, acorns, and other vegetable matter. Waldo L. McAtee (1926a) gives thus an excellent summary of its diet:

The White-breast has been observed to feed freely on beechnuts, to devour acorns and hickory nuts, to take maize from cribs, and to be very fond of seeds of sunflowers. These observations point to a fondness for mast which is characteristic of the nuthatch tribe. During the winter months nearly all of the food is mast, while through the spring and summer, much animal food is taken, often to the full capacity of the bird's stomach.

This is derived chiefly from the ranks of beetles, spiders, caterpillars, true bugs, and ants and other small hymenoptera. Besides these some flies, grasshoppers, moths, and millipeds are eaten. Among the insect food items known to have a detrimental relation to the forest are nut weevils, the locust seed weevils (Spermophagus robiniae), round-headed wood borers, leaf beetles, tree hoppers, psyllids, scale insects, caterpillars, and ants. The White-breast has been observed to feed also on larvae of gall flies, eggs of plant lice and of fall cankerworms, oyster scale (Lepidosaphes ulmi), and upon larvae of the gypsy moth and forest tent caterpillars. . . .

In the long run, the White-breast, no doubt, destroys a large number of forest pests, and while not so valuable as some of the more highly insectivorous birds, still deserves protection.

The birds are fond of suet, as everyone who maintains a feeding station knows. William Brewster (1936) gives this scene of a pair caching this delicacy:

The pair of Nuthatches came regularly to the suet, oftenest in the early morning. I watched them closely for half an hour this morning [March 17, 1911]. The male was digging out pieces up to the size of a large pea and carrying them away to store them in crevices in tree trunks and behind scales of loose bark. He took them to different trees and in all directions, usually going about 100 yards. Whenever the female was with or near him, he invariably employed her to carry off and cache the morsel. She took it from him without hesitation and flew, as he did, in various directions, chiefly to apple trees in the orchard. Curiously enough, he would not permit her to touch the main store of supply from which he was drawing. Whenever she attempted to do so, he attacked her quite viciously and drove her away. Yet the next moment he would give her the small pieces that he had just extracted.

Edward H. Forbush (1929) states: "Several ornithologists have doubted that they ever break nuts of any kind. There is credible testimony however to support the statement. Dr. C. W. Townsend says that he has twice observed the habit." Dr. Townsend (1905) continues: "On one occasion, when the bird was disturbed, it flew off with an acorn into which it had thrust its bill. The object was probably to obtain the larvae within."

Those of us who have fed nuthatches at our window ledges and have watched them feed at arm's length have had ample proof that the birds do crack and swallow pieces of nuts. I have frequently had a bird take a bit of nut meat from my hand and swallow it, or, if it were too large, take it to the corner of the shelf, as to a cranny of bark, and split it, and I have watched a bird crack open a cherry stone.

Prof. O. A. Stevens writes: "When they first appear in the fall, we have often fed them squash seeds, which they cache with great industry. I have at times watched an individual bird take six or seven seeds in succession in different directions, hunting for suitable places in trees, shingles, and other parts of houses."

Behavior.--The white-breasted nuthatch spends most of his day hopping over the bark of the trunks and main branches of large trees, generally moving head downward toward the ground. Francis H. Allen (1912) points out an advantage in this procedure, saying: "I suspect that by approaching his prey from above he detects insects and insect eggs in the crevices of the bark which would be hidden from another point of view. The Woodpeckers and the Creepers can take care of the rest."

Edward H. Forbush (1929) explains how the downward progress is accomplished. He says: "They seem to have taken lessons of the squirrel which runs down the tree head first, stretching out his hind feet backward and so clinging to the bark with his claws as he goes down; but the nuthatch having only two feet has to reach forward under its breast with one and back beside its tail with the other, and thus, standing on a wide base and holding safely to the bark with the three fore claws of the upper foot turned backward, it hitches nimbly down the tree head first." A photograph in Bird-Lore, vol. 31, p. 424, seems to corroborate this statement. However, I once had under observation for weeks a nuthatch that had lost his entire left foot, the tarsus ending in a stump, thickened at the end, and in spite of his deformity, he was able to clamber over the branches, both large and small ones, and even to hang head downward, clinging to a small branch with his single foot.

Sometimes a nuthatch will hop down to the very base of a tree and then continue on over the ground. Here the bird looks strange enough, accustomed as we are to see it in reversed position, as leaning forward it jumps or leaps along, reminding us not a little of a frog. Edward H. Forbush (1929) tells of "a pair that spent an entire forenoon going over the chips left under a large tree from which the loose bark had been scraped. The birds picked over this material very thoroughly in their search for insects and insects' eggs."

The tameness of the white-breasted nuthatch, or the lack of suspicion it shows toward human beings, is remarkable. With a little patience a bird may be induced to feed from our hand, especially if we are indoors and reach out through an open window to the food shelf where it is accustomed to feed. There are many such records in the literature. A striking example of trustfulness is related thus by E. M. Mead (1903), who while outdoors in Central Park, New York, fed a bird for two successive seasons: "So fearless is she that she will take food from my lips, shoulder or lap. Even an open umbrella over my head has no terrors for her. Although she manifested some annoyance at the appearance of the camera within 2 feet of us for more than an hour, during which time 12 exposures were made, still she repeated all her little tricks, not only once, but several times."

The bird displays remarkable agility in the air, on the bark of trees and small branches; it can catch a falling nut in midair, or scramble downward over the bark and overtake it, and it can hang upside down, swinging from a tiny branch. A. C. Bent mentions a bird that ran down a swaying rope "always head downward, and scolded me within 2 feet of my face."

Charles L. Whittle (1930) reports a banded bird known to have reached the age of 7 1/2 years.

Wilbur K. Butts (1927), after making a careful investigation of the feeding range of marked white-breasted nuthatches, remarks: "In the course of the study it soon became apparent that each pair did not wander freely about, but had a definite, restricted, though fairly large feeding range." This accords with the experience I had with a male bird which visited my feeding shelf daily, with one short interlude, for over a year. Butts (1931) gives the following interesting summary of a subsequent study of the bird:

1. All or nearly all the individuals of the Nuthatch found at Ithaca were permanent residents. There is no evidence of any migration in this locality. 2. Each pair of Nuthatches had a definite feeding territory throughout the year. 3. The size of the territory in the winter was about 25 or 30 acres in wooded country and apparently about 50 acres in semiwooded country. 4. They ranged over an approximately equal area during the nesting season, though it was not necessarily the same area. 5. Feeding stations had no effect on the feeding range of the Nuthatch. 6. Feeding stations should be about one-fourth of a mile apart for the Nuthatch. 7. The nest is built in or near the winter feeding territory. 8. Besides the mated pairs which have established territories there are a number of wandering birds. 9. In case of the disappearance of one member of a mated pair, its place may be taken by one of these wandering birds. 10. Nuthatches may nest in the same hole for successive seasons. 11. The large size of both winter and breeding territories is apparently not caused by inability of the birds to find sufficient food in a smaller area. They are able to obtain plenty of food quite near the nest. The feeding of the young birds is apparently not such a severe task as it is commonly supposed to be.

Francis Zirrer, of Hayward, Wis., writes: "The families stay together until about the end of November, as up to that time the old birds are still occasionally feeding the young, which at first are somewhat reluctant to come to the feeding table. Later, the old males usurp the table and chase, or try to chase, all others away. They tame readily, come to the hand for food, but know perfectly well the difference in size of the food; they will come, pick the first piece, but seeing a larger piece will pause a little, drop the first one and take the largest. If no food is on the table, they will come to the window, or visit the woodland dweller at his place in the woods, where he works at his winter supply of fuel, often a considerable distance from home; and there is usually no rest until he returns to the cabin and fills the table with a fresh supply of food. They become so used to a certain person and his call that they will, if within hearing distance, come and follow long distances through the woods. Met in the woods during breeding season, often more than a mile away, they will come at the call and sit on the hand, head or shoulder. Of course, it is advisable to carry something in the pockets, which one used to such things usually does. As a rule, they are quite fearless, even bold; during the nesting season of the goshawk, which nested several years a few hundred yards from the cabin, the bold little imps inspected fearlessly the limbs and trunk of the nesting tree, apparently not fearing the fierce raptors a few feet or yards away."

Voice.--Most of the notes of the white-breasted nuthatch bear a decided resemblance to the human voice; they seem to be spoken or whistled. A song, for example, may be likened to a man whistling to a dog--a regular series of about six or eight notes, sometimes more, sharply accented, striking the same pitch, each with a slight rising inflection. The pitch is commonly D next but one above middle C. When a bird is singing near at hand the voice loses some of its whistled quality and becomes full, resonant, almost mellow. The song has been variously rendered into syllables such as hah-hah-hah, tway, tway, what, what, too, too, and whoot, whoot. These renderings represent the song heard from different distances, and all of them suggest it somewhat. Occasionally the pitch of the song falls slightly at the end; sometimes the pitch undulates in slight degree; and rarely the bird crowds 20 or more rapid notes into a song of normal length.

Some years ago I had a male nuthatch under close observation where I could hear it practically every day for a full round of the seasons. The following quotation (W. M. Tyler, 1916) gives a summary of his notes:

The Nuthatch sings every month in the year; even on the coldest days of January he occasionally sings a few times in the early morning--I have heard the song when the temperature was zero; in February songs are more frequently heard, but singing during this month is still irregular. The chief singing period is from the first of March until the last of May; during these 3 months the male sings continually. June is a month of comparative silence (I have only five records of song); in July and August songs are heard almost as infrequently as in winter, and during the last 4 months of the year singing is still rarer. In winter, singing is confined to the early morning hours--soon after sunrise--and even during the spring it is rare, before the first of April, to hear a nuthatch sing in the afternoon. In autumn an occasional song is heard in the warmest part of the day.

In addition to his songs, our Nuthatch utters five different notes: (1) The simplest of these, and by far the most frequently used note of his vocabulary, is a high, short syllable, quietly pronounced, much aspirated, sounding like "hit." This note is given when the bird is perched and when he is in the air, both by a solitary bird and by a pair when they are together. It is both a soliloquizing and a conversational note and is associated as a rule with a calm mood. (2) The well-known ejaculation "quank," a call at certain distances remarkably suggestive of the human voice, is often employed when the bird seems excited. At such times the note is delivered with much vigor; on other occasions it is apparently used as a call between a pair of birds. This note and the "hit" are the only notes I have heard from the female bird. The "quank" call is very often doubled and is frequently extended into a loud, rattling chatter. As in the case of the song, the "quank" appears very much rounder, fuller and more resonant when heard near at hand. At short range it has a rolling "r" sound. (3) A low-toned "chuck" is sometimes addressed to the female. (4) On several occasions I have heard the male bird utter a growl (deep in tone for a bird) as he dashed in attack at a Sparrow. (5) A note which I have heard but rarely is a long, high whistle with a rising, followed by a falling inflection. Our word "queer" recalls the note which bears a decided resemblance to one of the Pine Grosbeak's piping calls. The note has a ventriloquial property, appearing to come from a distance when, in reality, the bird is close by. I heard this note several times in late February and early March, generally between songs in the early morning.

Francis H. Allen says in his notes for May 9, 1939: "From a pair feeding in trees I heard a note that was new to me often repeated. It was a soft, two-syllabled note that might be rendered k daap. Sometimes I saw that it came from the female, and I never was sure that I heard it from the male. The note was at least as high-pitched as the familiar tut, which the birds also uttered frequently. Twice I saw the male feed the female. The feeding was accompanied by a faint little rapid chatter that was new to me. The k daap note was so different from the ordinary calls of the species that I did not suspect a nuthatch as the author when I first heard it."

Field marks.--The white-breasted nuthatch is a small, thick-set bird with a pearl-gray, unstreaked back, shining black crown, and black-and-white wings and tail. The side of the head is white, without an ocular stripe, and the bill is long, straight, and dark. It is the largest of our nuthatches and does not resemble the smaller species closely in plumage. Its confirmed habit of hopping downward over the bark of tree trunks distinguishes it readily from the warblers, kinglets, and other small avian frequenters of the woodland.

Enemies.--The white-breasted nuthatch is one of the species victimized by the cowbird, but cases are apparently rare, for Dr. Herbert Friedmann (1934) says: "I knew of three instances before; now another has come to my attention, a set of six eggs of the nuthatch and one of the Eastern Cowbird, collected May 5, 1912, at State College, Pennsylvania, by R. C. Harlow."

R. W. Williams (1918) gives this lively description of an attack of two red-headed woodpeckers upon a nuthatch's nest and young:

Bright and happy days for the birds, old and young, ensued, until one morning before breakfast (May 9) two Red-headed Woodpeckers arrived on the scene and inspected the box. I did not attach much significance to this and contented myself, before leaving for my office, with frightening them away by vigorous gesticulations and by small sticks thrown at them. These methods seemed to suffice for a time. Later in the day, however, I received a message that the Woodpeckers were enlarging the entrance and possessing the box, throwing out the young Nuthatches--three having already been cast to the ground--and altogether evicting the parents, which, grief-stricken, were looking on from nearby stations. The red-headed ruffians were at the box when I reached home that afternoon but they disappeared at my approach. I procured my gun and took a position from which I would be sure to reach them if they returned. I had not long to wait. One of them alighted at the entrance of the box. I fired and the bird fell to the ground directly under the box. Both of the Nuthatches flew to the base of the tree and, clinging there within a foot of the ground, regarded the Woodpecker for more than a minute, with exhibitions of keen satisfaction and exultation.

I found another of the young Nuthatches dead a few feet away from the tree. None of the young birds was mutilated to any extent, from which circumstance it seems probable that the Woodpeckers were not in quest of food, but distinctly bent on mischief.

Harold S. Peters (1936) mentions two flies, Ornithonica confluenta Say and Ornithomyia anchineuria Speiser, which have been found in the plumage of this bird.

Fall and Winter.--As we have seen above, no prominent migration of the white-breasted nuthatch has been noted. P. A. Taverner and B. H. Swales (1908) report from Point Peele, Ontario, Canada: "This species, though met with on nearly all visits, has never been very common. Usually a few scattered individuals have made a day's record. Our date of greatest abundance was October 14, 1906, when 10 were listed. . . . Our fall dates are conflicting, but seem to indicate that migrants arrive irregularly from the last of August to the middle of September."

The nuthatch, as we know him best, is an autumn and winter bird. We meet him hopping about the leafless trees, settled in some woodland, generally in the company of his mate. Here through the whole winter he remains in a domain that he has established as his winter quarters, and where he roosts in some sheltered cavity. He often appears to be alone, but if we listen we may hear his mate answering from a distance his little piglike, grunting call. Thus the pair keeps in touch, and when, drifting through the woodland, they meet and feed in close proximity, they exchange salutations back and forth with their soft, conversational hit, hit. The chickadees and creepers often join them for a time, all three species, with sometimes a downy woodpecker, searching for food in the same trees, until the more restless birds flit onward and leave the nuthatches alone again.

White-breasted Nuthatch* Sitta carolinensis

*Original Source: Bent, Arthur Cleveland. 1948. Smithsonian Institution United States National Museum Bulletin 195: 1-12. United States Government Printing Office