Pygmy Nuthatches are social birds, and up to several relatives may help a breeding pair with food deliveries and territory defense. These helpers are probably one reason why the Pygmy Nuthatch has higher nest success than most other songbirds at nearly 90 percent.
Pygmy Nuthatches are capable of excavating their own cavities, but they will also use old woodpecker holes. Territories are used for foraging year-round, but usually aren’t defended outside of the breeding season. A form of controlled hypothermia is used by Pygmy Nuthatches to survive cold winter nights.
On this page
Description of the Pygmy Nuthatch
The Pygmy Nuthatch is very small, with grayish wings, a white throat, buffy underparts, a grayish-brown cap with a darker line through the eye, and a long bill. Length: 4 in. Wingspan: 8 in.
Seasonal change in appearance
Similar to adults.
Pygmy Nuthatches are primarily found in pine forests.
Pygmy Nuthatches eat insects and seeds.
Pygmy Nuthatches forage primarily on high, outer branches of trees, but also on trunks. flocks. They often occur in flocks.
Pygmy Nuthatches occur in parts of the western U.S. and Mexico. The population appears to be stable.
Nesting pairs of Pygmy Nuthatches may have additional helpers that bring food to the brood.
Pygmy Nuthatches roost within cavities in tight clusters of several to 10 or more birds to survive cold winter nights. Roosts with up to 150 birds have been reported!
Pygmy Nuthatches often store seeds for later use.
The calls include loud chips or squeaks.
- The Brown-headed Nuthatch, whose range does not overlap, has a darker brown cap and is whiter below.
The nest is made of bark fiber and soft plant material and is placed in an excavated cavity in a dead tree.
Number: Usually lay 6-8 eggs.
Color: White with darker markings.
Incubation and fledging:
The young hatch at about 15-16 days, and leave the nest in another 20-22 days, though continuing to associate with the adults for some time.
Bent Life History of the Pygmy Nuthatch
Published by the Smithsonian Institution between the 1920s and the 1950s, the Bent life history series of monographs provide an often colorful description of the birds of North America. Arthur Cleveland Bent was the lead author for the series. The Bent series is a great resource and often includes quotes from early American Ornithologists, including Audubon, Townsend, Wilson, Sutton and many others.
Bent Life History for the Pygmy Nuthatch – the common name and sub-species reflect the nomenclature in use at the time the description was written.
SITTA PYGMAEA PYGMAEA VigorsHABITS
The type race of the pygmy nuthatch is now restricted to a very narrow range in the Transition Zone of the coast region of California, from San Luis Obispo County to Mendocino County.
A. J. van Rossem (1929) says that “the color characters distinguishing pygmaea from melanotis * * * are more brownish pileum and nape, combined with a relatively indistinct ocular streak which is never prominent and in extreme cases so nearly concolor with the head as to be almost indistinguishable.”
Grinnell and Linsdale (1936) say that this subspecies, which was named from specimens collected at Monterey, “is restricted quite closely to the southern portion of the humid coast strip,” as mentioned above. They further state:
[It] “lives commonly in the same habitat, the coniferous forest, with the Santa Cruz Chestnut-sided Chickadee; and it does so, therefore, compatibly. Our observations show the niche occupied by the nuthatch to be essentially different. While the two birds have about the same forage beat and cruising radius, often indeed seen closely associated, the nuthatch seeks (at least in the season of greatest food scarcity) static insect food in crevices of dry cones, twigs, and smaller branches in the subperipheral parts of the trees, and it uses its specialized digging tool (the bill) to dislodge or uncover these insects. In other words, the nuthatch has a food source beyond the usual reach of the chickadee. And then, too, with suitably rotted boles of trees available, it digs its own nesting cavity; it does not tolerate the chickadee.
Nesting: The same observers write:
The breeding season for this species [in the Point Lobos Reserve] was a long one, with a prolonged period of preparation. As early in the spring as February 18, there were signs of pairing in this bird. In an excited flock in a pine, one Individual was seen feeding another. Later, on several occasions, a male (?) was seen to feed its mate.
Actual excavation at a nesting site was noted first on March 20. Just before noon, a nuthatch was digging 15 feet up on the west side of a 25-foot pine stump. It left the cavity, barely started, but returned again in 5 minutes. More than a month later, on April 24, a nuthatch, then out of sight, was still digging at this cavity.
Thirty-eight occupied nesting cavities were found, all of them in pines or dead remains of pines. The sites selected were high ones, averaging 30 feet above the ground and running as high as 60 feet. Only seven nests were found lower than 20 feet and only one under 10 feet. Sometimes the excavation was started at some crevice or break already existing in the tree, hut more often, and especially when the wood was partly decayed, it was started on a plain surface. Once a cavity started by a hairy woodpecker was deepened and occupied by a pair of nuthatches. * * *
The bluebirds were the most serious competitors of this species for nest sites, and in several instances, in which the entrances were of sufficient size, they temporarily or even permanently ousted the smaller birds from a cavity. Nearly always in such cases the nuthatches had been the excavators, but the larger birds seemed usually to be the aggressors. At one stump where nuthatches were digging only 2 feet below a bluebird’s nest, there were alarm notes and activity when the bluebirds were near. The nuthatches usually retreated, but they sometimes kept on working.
The birds at one nest showed great excitement when a hairy woodpecker came near. Chickadees were competitors of close to nuthatch size. Once one was seen pursued by a chickadee, and at another time one was chasing a chickadee. In general, however, these two species avoided one another by nesting at wholly different levels. One pair of nuthatches which was feeding young chased away a male linnet and, later, a violet-green swallow, from the vicinity of the nest.
Mrs. Amelia S. Allen tells me that in fall these nuthatches “wander through the lower valleys where their chattering notes betray their presence in the tops of the trees among the cones. At Inverness, in Mann County, they are much at home among the Bishop pines, and at Carmel, in Monterey County, among the Monterey pines.”
The eggs of this subspecies are indistinguishable from those of the following form. The measurements of 40 eggs of the present race average 15.4 by 12.1 millimeters; the eggs showing the four extremes measure 16.3 by 12.8, 14.5 by 12.3, and 14.7 by 11.2 millimeters.
Range: Southern British Columbia to southern Mexico.
The pygmy nuthatch breeds north to southern British Columbia (Cawston, Penticton, and Newgate). East to southern British Columbia (Newgate); western Montana (probably Belton and the Beartooth Mountains); Wyoming (near Laramie); Colorado (Estes Park, mountains west of Boulder, Golden, and Fort Garland); possibly northeastern Oklahoma (Kenton); New Mexico (Sangre de Cristo, Capitan, and Sacramento Mountains); southwestern Texas (Guadalupe Mountains); and Veracruz (Las Vigas). South to Veracruz (Las Vigas); Puebla (Mount Orizaba and Rio Frio); Morelos (Huitzilac); and MichoacFin (Mount Tancitaro). West to Michoac~n (Mount Tancitaro); Jalisco (San Sabastian); Baja California (Sierra San Pedro Martir and Laguna Hansen); California (Mount Pinos, Monterey, Point Reyes, and Inglenook); Oregon (Pinehurst and Warm Springs Reservation); Washington (Seattle and Mount Baker); and British Columbia (Cawston).
The pygmy nuthatch is not migratory, but it does wander about some in winter, at which time it has reached western Nebraska.
The distribution as given is for the entire Species, which has been divided into four subspecies or geographic races within our limits. The pygmy nuthatch (S. p. pygmaea) occurs in the coast region of California from Mendocino County south to San Luis Obispo County. The white-naped nuthatch (S. p. leuconucha) breeds from Riverside and San Diego Counties, Calif., south through the San Pedro Martir Mountains, Baja California. The Nevada nuthatch (S. p. canescens) occurs in the Charleston and Sheep Mountains in southern Nevada. The black-eared nuthatch (S. p. melanotis) occupies the Rocky Mountain region from southern British Columbia southward to New Mexico and Arizona, and possibly Sonora, and the Sierra Nevada in California.
Egg dates: Arizona: 9 records, May 7 to June 6.
California: 89 records, April 17 to June 27; 45 records, May 16 to June 3, indicating the height of the season.
Colorado: 22 records, May 13 to June 19; 11 records, May 22 to June 12. Oregon: 17 records, May 3 to June 21.
SITTA PYGMAEA MELANOTIS van Rossem
Up to the time that this race was separated, in 1929, all the pygmy nuthatches of the western United States were supposed to belong to the type race. The species is widely distributed and was always known to all the earlier writers as the pygmy nuthatch, Sitta pygmaea pygmaea. But melanotis, as now recognized, is the most widely distributed and the best-known race and must be given the most consideration here, even if the new name is not always used.
A. J. van Rossem (1929) gives as the subspecific characters of melanotis: “Similar in size to Sitta pygmaea pygmaea, but top of head and nape decidedly darker and more slaty (less brownish); streak from bill through eye broader and often nearly black, contrasting strongly with the white or buffy white malar region. Differs from Sitta pygmaea leuconucha in decidedly smaller size and very much darker coloration.”
It occupies the entire Rocky Mountain region, from southern British Columbia and northern Idaho south to the Mexican boundary, and west to eastern Washington, eastern Oregon, the Sierra Nevada, and the San Bernardino Mountains of California. Mr. van Rossem (1929) says that “in southern California, intergradation with leuconucha is very gradual and birds from the extreme southern Sierras, Mt. Pinos, the San Gabriel and San Bernardino Mountains are definitely larger than northern Sierra and Rocky Mountain series.”
The black-eared nuthatch is a mountain bird, breeding in the Transition Zone at elevations from 3,500 to 10,000 feet in various parts of its range. Its distribution seems to coincide very closely with that of the yellow pine, where it is generally common and often really abundant. In the San Bernardino Mountains, Dr. Grinnell (1908) found it “most numerous in the lower Transition zone, in the Jeffrey and yellow pine belt.” It is doubtless found to some extent among other species of pines, though the yellow-pine belt seems to be its favorite breeding ground. In the Huachuca Mountains we found it very common in the pines above 8,000 feet and up nearly to the summit, where the open growth of pines ended at about 9,000 feet. It reaches about the same altitudes in Nevada and Colorado; and, in New Mexico, Mrs. Bailey (1928) says: “The Pygmies are characteristic birds of the Transition Zone yellow pine belt, following it on steep hot slopes to the extreme upper limit of the zone, sometimes as high as 10,000 feet.”
According to Grinnell and Linsdale (1936) it is resident “along the west flank of the Sierra Nevada, at altitudes of 3,500 to 6,000 feet, according to slope exposure and other factors.”
W. E. Griffee tells me that “the black-eared nuthatch, like the short-tailed chickadee, is found throughout the pine forests of eastern Oregon.” According to Fred Mallery Packard (MS.), of Estes Park, Cob., “in spring and fall, small bands of pygmy nuthatches wander through the yellow pines, calling noisily; but they scatter during the nesting season and are seldom heard then. Nests have been found, between June 5 and 18, at 8,200 feet, and it is certain that they nest well into the Canadian zone. There is a vertical migration, sometimes to the plains.”
Nesting: It was on the summits of the Huachuca Mountains that I made the acquaintance of the tiny black-eared nuthatch, then known as the pygmy nuthatch. On these summits at elevations between 8,000 and 9,000 feet, above the steepest slopes, the surface of the ground was nearly level in some places, or rolling in gentle slopes in others. It was covered with a fine parklike, open forest of tall pines of two or three species that towered skyward to heights of 80 or 100 feet. Scattered through this forest were a number of tall dead pines and lower stubs. Here, on May 7, 1922, many of the nuthatches were already paired and were busy with their preparations for nesting. The nesting holes were easy to recognize, as little circular openings, usually near the tops of the dead pine stubs and often under the stump of a branch. One nest that we investigated was 30 feet from the ground in such a situation, but no eggs had been laid in it. Another, similarly located, was not examined, as we were apparently too early. My companion, Frank Willard, returned to this locality on May 30 and collected three sets of eggs of this nuthatch, consisting of six, seven, and eight. eggs, respectively; the nests were all in dead pine stubs, 20, 40, and 50 feet above ground; the depth of one cavity, evidently excavated by the birds, was 10 inches; the nest lining consisted mainly of “pine bud hulls,” with a few feathers.
Nests are not always placed at such heights above ground. In the San Bernardino Mountains, at about 7,000 feet elevation, Dr. Grinnell (1908) found a nest “in a rotten pine stub eight feet above the ground. The cavity seemed to have been excavated by the birds themselves. Two blows on the stub brought out the setting bird, which at once disappeared. After a while what proved to be the male nuthatch made his appearance with an insect in his mouth, an indication that the male feeds the female on the nest. The nest was a felted mass of rodent fur and plant down. There were seven slightly incubated eggs.”
Irene G. Wheelock (1904) writes:
At Lake Tahoe a hollow post several feet out In the water held a nest of these gray midgets, the entrance being a crevice scarcely large enough for a mouse. Both birds worked busily carrying feathers into this crevice until It seemed there must be at least a peck of them tucked away Inside. Although I stood In a boat with hand resting on the post not a foot from their doorway, they came and went as unconcernedly as if no one were within miles of them. * * * Another nest found, June 14, ten feet from the ground In a dead pine was also entered through a crevice; the birds displayed the same fearlessness, going Inside with food, while the bird-lover stood on her horse’s back and tried to make the opening large enough to admit a friendly though curious hand. The brave little bird would light on the trunk just above the nest hole, and, running quickly down, dodge In when the angers of the investigator were pulling at the crevice.
Another nest near Lake Tahoe is reported by Claude Gignoux (1924), in “a hole about 10 feet from the ground in an upright post. * * * The nest, entered by a small, irregular orifice, was in a decayed portion of the pole, where excavation was easy. * * * The pole in which the nest was placed stood at the junction of two board walks, not over 20 feet from an occupied cottage. People were passing every few minutes, workmen were repairing a drain and board walk within 100 feet, and automobiles were being repaired, moved about, and their engines raced by mechanics, within 50 or 75 yards. The adult birds were so intent upon their duties [feeding their young] that none of these activities disturbed them.”
There is a set of eggs in the J. P. Norris collection taken from a deserted woodpecker’s hole, one from a hole bored by the birds in a cottonwood tree, and another from “under loose bark on a dead tree”. Probably any suitable cavity that is available may be occupied.
From the mountains northeast of Silver City, N. Mex., J. S. Ligon wrote to Mrs. Bailey (1928) in April 1919, as follows: “I watched two of these little fellows laboring at a nest hole 18 feet up in a dead pine. One was inside, making the noise of a woodpecker. I watched the performance for about 10 minutes, during which time it made three trips out to the entrance to fling the chips and dust to the wind with a quick shake of the bill. It came out apparently to rest and the other went quickly in, and after it had hammered a little, came up with its cuttings, flinging them away and quickly returning. On the 18th or 19th, it seemed that all the Pygmies, as if by general order, were working in nest holes.”
Mr. Griffee writes to me that the nests of this nuthatch, in eastern Oregon, “usually are in ponderosa pine snags. The larger snags, after being dead for several years, have a layer of punky sapwood, 3 or 4 inches thick, and deep season checks which need only a little enlarging to serve as entrances to nesting cavities. Since the entrances are irregular in shape, being 1 to 1¼ inches wide by 1¼ inches or more high, and usually 10 to 25 feet up, they are not at all conspicuous. The bottom of the nesting cavity is usually about 8 inches below the entrance, and in some cases it is so small that a family of six or seven young nuthatches must find it very cramped quarters. The lining, often scanty, is of shreds of bark, bits of cocoons or of wool, and a few feathers.”
Eggs: Pygmy nuthatches may lay anywhere from four to nine eggs to a set; the smaller numbers are unusual, and most of the sets consist of six to eight eggs. They vary in shape from ovate to short-ovate and have practically no gloss. The ground color is pure white, and they are usually unevenly and rather sparingly sprinkled with fine dots of reddish brown or brick red, “hazel,” or “vinaceous-cinnamon”; some eggs are more heavily spotted about the larger end, rarely elsewhere, with these colors or “chestnut.” Eggs of this species do not show so much variation as those of some of the other nuthatches, and are not so handsomely marked. The measurements of 40 eggs average 15.3 by 11.9 millimeters; the eggs showing the four extremes measure 16.3 by 11.4, 15.0 by 12.5, 14.2 by 12.2, and 15.2 by 11.1 millimeters.
Young: I can find no definite statement as to the period of incubation, which is probably about 14 days. Perhaps both sexes share in this duty, but the fact that the male is known to feed the female on the nest indicates that she probably does most, if not all, of the incubating. Both parents feed the young in the nest and for some time after they leave it. Mrs. Wheelock (1904), at the nest she watched, noted that “both male and female were busy hunting some sort of white larvæ that they obtained from an old stump. The adults did not swallow these, but carried them in their bills: which convinced me that the nestlings were at least five days old.”
Mr. Gignoux (1924) writes:
Both parent birds were engaged in the task of carrying what appeared to be flies, worms, and white grubs, and both birds were often in sight at the same time. The first visit was recorded at 2:26 In the afternoon and by 3:27 the birds had made 24 calls, carrying food each time. At this rate the adult birds were making over 300 trips a day. The longest Interval between visits was 8 minutes, the shortest was half a minute. The parents did their foraging in nearby pine trees and well up from the ground, from about 50 to 50 feet or more high. The insects were thrust into the bills of the young the instant the parents arrived, without the slightest delay, and the old birds were off for more, now and then stopping a second or so to remove material from the nest. * * *
During the days on which I watched the birds, foraging was done in a group of about 20 large pine trees. The flights were always direct from near the nest to and from these pines. I measured what seemed the distance of these trees from the nest and estimated that 150 yards was the average round trip and that the total distance traveled each day was approximately 30 miles.
Mrs. Wheelock (1905) tells of another nest, not those referred to above:
In this case there were newly hatched young in the nest; and, as the adults went inside to feed them not more than two feet from my eyes, I was able to see perfectly that the food was carried in the throat. Of course this could only mean regurgitation; hut not until the third day could I get at the nestlings to examine the crops. The contents consisted of larvae of Insects and ant eggs, all partially digested. On the fifth day the examination indicated the presence of fresh or unregurgitated insect and grass food. On the sixth day most of the food given was fresh, but on two occasions the adults visited the nests with no visible supply in the hills. No record was kept of this brood after the sixth day. Two other broods of this species were recorded at the same place and with practically the same results.
J. Eugene Law (1929), while studying the behavior of a pair of these nuthatches, noted that “when a fecal sac was brought out, it was not dropped in flight but was carried out and left attached to some high limb. One particular limb of another tree received it on more than one occasion that I saw. After depositing the feces the bird wiped and rapped its beak on the limb vigorously.” He also relates the following:
One day as Dr. Tracy I. Storer and I stood near, a parent, grasping with its beak, seized a nestling by the shoulder, and after a rough tussle pulled the chick out and let it go fluttering to the ground. There, after a rest, during which parental solicitude obviously urged action, the fledging fluttered along the ground directly to the base of a huge live pine near-by and began to climb. A yard or two at a time, intervalled by long rests, it finally worked up the trunk to the first limbs, some 50 feet. The astonishing thing was that the fledgling elevated itself up trunk mainly by rapid fluttering of its wings while keeping the body axis parallel with the perpendicular tree trunk, all the while pawing the bark furiously with its feet. Progress was slow, dangerously near no progress, it seemed.
After the young have left the nest, they travel about in a family party until they learn to shift for themselves. These parties later join in larger flocks, made up of several families, and roam through the tree tops during fall and winter.
Plumages: Ridgway (1904) says that young pygmy nuthatches in juvenal plumage are “similar to adults, but pileum and hindneck gray, only slightly, if at all, different from color of back, and sides and flanks pale buffy brown or brownish buff instead of gray.” Apparently, after the postjuvenal molt in August, old and young birds are practically indistinguishable. Adults have a complete postnuptial molt beginning about the middle of July and lasting through most of August; I have seen adults in fresh plumage as early as August 20. In fresh fall plumage the colors are richer and darker, the under parts decidedly buff, and the pale spot on the nape is partially concealed with’ gray tips.
Food: Prof. F. E. L. Beal (1907) examined only 31 stomachs of the California races of the pygmy nuthatch and found the food to be divided into approximately 83 percent animal matter and 17 percent vegetable. The largest item of animal food was Hymenoptera, mostly wasps with a few ants, amounting to 38 percent of the whole. Hemiptera came next, 23 percent; “a large proportion of these belong to the family Cercopidae, commonly known as spittle-insects, from the fact that they develop inside of a froth-like substance resembling saliva produced in summer upon grass and various plants and trees. While none of these insects have yet become pests, there can be no doubt that collectively they do considerable harm to plants, as sometimes they are very abundant and subsist entirely upon their sap.” Eighteen out of twenty stomachs from the pine woods of Pacific Grove “contained remains of Cercopidae, and six were filled with them. The average for the 18 stomachs is a little more than 76 percent of all the food.” Beetles of various families formed about 12 percent of the food, caterpillars 8 percent, and spiders 1 percent. “The vegetable portion is made up almost entirely of seeds, of which a majority are those of conifers, as was to be expected from the habits of the bird.”
A few other items have been mentioned by others. R. C. Tate (1925) adds, from Oklahoma, moths, pine nuts, and grasshoppers. Junius Henderson (1927) quotes from Professor Aughey’s first report that “four Nebraska stomachs averaged 23 locusts, 4 other insects and four seeds each.”
Most of the pygmy nuthatch’s food is obtained in the topmost branches of the pine, where it climbs over and under the branches and out to the outermost twigs and among the pine needles. But it also forages on the trunks in true nuthatch fashion, looking for hidden insects, or resorts to the ground to pick up insects and seeds. It can crack the pine nuts with its strong little bill and pick out the seeds. It has been seen darting out into the air after flying insects, or fluttering in front of the terminal twigs of the conifers to pick off insects while poised in the air.
Behavior: As may be seen from some of the above quotations, pygmy nuthatches are tame, confiding little birds, showing great confidence in human beings or being quite oblivious to their intimate presence; and they have even been known to pursue their nesting activities close to those of humans, apparently unafraid. Their behavior is much like that of their near relatives, the brown-headed nuthatches of the southeastern States; like them they live mostly in the tree tops in merry little parties; they are even more gregarious than their eastern cousins. Except when the pairs are busy with their family affairs, these little birds are almost always seen in small flocks, which increase greatly in size during fall and winter. Mr. Swarth (1904b) says: “During the migrations they seem to form a sort of nucleus for other birds to gather around, and are usually accompanied by a number of migrating warblers, vireos, etc. Many of them [in Arizona] remain in small flocks up to the middle of May, though others may be seen at work at their nests in some old stump early in April; so by the time the last of them are paired off, those that first went to work are nearly ready to appear with their broods, and there is consequently hardly any time when Pygmy Nuthatches are not to be seen in flocks.”
These flocks of sociable little birds are full of incessant activity, as they drift through the tree tops in loose formations, twittering constantly to keep in touch with each other, reminding one of the flocks of bushtits that travel in a similar disconnected way through the shrubbery, yet definitely associated. In some ways, too, their behavior reminds one of the titmice or kinglets, especially in their feeding habits.
J. Eugene Law (1929) has published an interesting paper on the climbing technique of this nuthatch, well illustrated with photographs showing the specialized use of the feet. He says: “Down-tree progress for a nuthatch seems to be a series of sidling hops or drops. While the bird is moving, its body rarely, perhaps never, parallels the axis of the tree, and at each pause one foot is usually apparent, clinging up-trunk, its grasp transverse to the axis of the tree. When the bird stops, its body may turn so that the body and head point directly downward, and even then there is always that foot up-trunk holding on while the other foot holds the body out from the tree. * * * It is obvious, if we think a minute, that in this position the function of the up foot is to cling by the toes, while that of the down foot is to support. * * * The sole of the lower foot is depressed against the trunk while that of the upper foot is free.” All these points are well shown in his photographs, with the feet widely spread in all crosswise or head-downward positions.
Very little is known about where and how birds spend their nights. Night roosting of passerine birds has been observed in only a few instances for very few species. From what little has been seen, we might infer that hole-nesting birds may prefer to roost in such cavities, though other methods of roosting have been observed. Mrs. A. H. Jones (1930) watched a family of black-eared nuthatches, in Colorado, go to roost for several nights in a bird box made of slabs and attached to the trunk of a large yellow pine. They came regularly each night at about 6:45, entered the box, and apparently spent the night there. But they were not allowed to enjoy this comfortable retreat very long before a house wren appeared one morning and tried to take possession of the box. For a few nights the nuthatches were able to drive out the wren, but eventually the wren secured a mate and filled up the box with twigs, which the nuthatches were unable to remove, and the nuthatches had to give it up.
Voice: Pygmy nuthatches are noisy birds, and their notes are quite different from those of other nuthatches; especially noticeable is the entire absence of the familiar yank-yank of the white-breasted species. Ralph Hoffmann (1927) describes it very well as follows: “They call to one another incessantly with a high staccato t?-d?, t?-d?, t?-d?, which becomes a rapid series of high cheeping notes when a number are together, and in spring is combined with a vigorous trill. As they fly they utter a soft kit, kit, kit.” Robert Ridgway (1877) thought that “the notes of this species greatly resemble in their high pitch the ‘peet’ or ‘peet-weet’ of certain Sandpipers (as Tringoides and Rhyacophilus), but they are louder and more piercing.”
Field marks: The pygmy nuthatches can be easily distinguished from the other two western nuthatches by the absence of the conspicuous black caps of the white-breasted and red-bellied species. It is much smaller than the former and slightly smaller than the latter.
Its coloration is dull, and the black line through the eye and the white spot on the nape are not very conspicuous, except at short range. Its very short tail, its jerky flight, and its habit of crawling over trunks and branches mark it as a nuthatch.
Fall and winter: These are the seasons of most conspicuous activity and the greatest concentration into large flocks. As fall approaches the little family parties join with other families, adding to their numbers as the season progresses, until the flocks increase to as many as 50 or 100 birds. As these great flocks travel through the woods, they may occupy several trees, but, like the flocks of bushtits, they keep in touch with the general throng with their ceaseless chatter, and – – the main flock moves along. Associated with these flocks there may be a few white-breasted nuthatches, chickadees, titmice, warblers, or creepers, or perhaps one of the smaller woodpeckers, all intent on their own affairs, but on peaceful terms. The woods seem alive with the merry parties, in which the shrill notes of the nuthatches are most conspicuous.
In winter the nuthatches retreat more or less from the higher altitudes in which they nested, and drift downward, Mrs. Bailey (1928) says as low as 4,000 feet in New Mexico. They descend to some extent from the pine belt and may be seen foraging among the evergreen oaks, or in the juniper and pinyon belt, at this season. But at the first hint of spring they move up again into their beloved yellow pines.
SITTA PYGMAEA LEUCONUCHA Anthony
This nuthatch was originally described as a local race, living in the higher parts of the Sierra San Pedro Mártir in Baja California, but it is now also recognized as the resident form in the southern counties, Riverside and San Diego, in California. A. J. van Rossem (1929) remarks: “Leuconucha in typical form occurs only south of the Lower California. boundary. Birds from north of that point are somewhat intermediate toward melanotis, but a good series from the San Jacinto Mountains demonstrates clearly that leuconucha extends to that range.”
A. W. Anthony (1889), in naming it, says that it “differs from S. pygmaea in larger bill, grayer head, more conspicuous nuchal patch and whiter underparts. Compared with the other races, leuconucha is characterized by largest size, particularly of bill; paler, more ashy coloration of the upper parts, and least buffy underparts. I can not agree that the amount of white on the nape is of diagnostic value.”
Mr. Anthony (1893) called the white-naped nuthatch “the most abundant species on the San Pedro Mártir mountain; found everywhere in the pines. Upon our arrival May 5 this species was mating; noisy little companies of five or six to a dozen were seen chasing one another through the pines, chattering and calling from daylight till dark; although dozens of nests were discovered all were practically inaccessible. A favorite location for the burrow was on the under side of a dead branch, well away from the trunk of a large pine, and from twenty-five to a hundred feet from the ground.”
The eggs of the white-naped nuthatch are apparently indistinguishable from those of the other races of the species. The measurements of 23 eggs average 15.7 by 12.0 millimeters; the eggs showing the four extremes measure 16.3 by 12.3, 16.0 by 12.4, 15.0 by 11.7, and 15.4 by 11.6 millimeters.
SITTA PYGMAEA CANASCENS van Rossem
Mr. van Rossem (1931) described this local race of the pygmy nuthatch as “exactly resembling Sitta pygmaea leuconucha Anthony of northern Lower California in pale, ashy gray coloration, but size, particularly of bill, decidedly smaller. Similar in size to Sitta pygmaea melanotis van Rossem of the Rocky Mountains, but coloration paler and more ashy throughout, particularly on the head. Measurements of the type, which was selected as showing the racial average in size and color, are: wing, 64.0 mm.; tail, 34.0; culmen from base, 15.0.”
He gives the range as “Charleston and Sheep Mountains, extreme southern Nevada, where resident in the yellow pine association from 7,000 to 8,500 feet,” and says: “The series of 11 cane8cena are all in relatively fresh fall plumage, indeed seven of them had only just completed the annual moult at the time of collection. The color characters are, therefore, true ones and not the result of wear or fade. * * * The Lower California race, leuconucha, the only one resembling canescens closely in color, measures on the basis of 10 adult males from the San Pedro Mártir Mountains: wing, 68.0 mm.; tail, 36.0; culmen from base, 18.2.”