Chapter C: J. Maynard (1896) states, concerning its habits, as follows (2)

working on an oak-trunk, not three feet above the base;
while the trees around harbored unnumbered Bridled
Tits (_Baeolophus wollweberi_), Lead-colored Bush-tits
(_Psaltriparus plumbeus_) and Rocky Mountain Nuthatches
(_Sitta carolinensis nelsoni_). Very often did I run across
a similar assemblage, but rarely were there more than one
or two Arizona Woodpeckers in it. There is no recollection
at hand, of noting above four adult woodpeckers of this
species in view at once; more likely to chance upon a
solitary individual than a pair at any time. The noisiest
occasion I can accredit to the species occurred one spring
day when two adult females were located, perched upon
a horizontal limb of a madrona, facing each other, and
emitting a continuous volume of characteristic woodpecker
notes, the effect being heightened by that peculiar
muscular movement which accompanies the vocal utterances of
some Pici. The continuity was possible by a relay system;
and so engrossed were the participants, that I approached
to directly under the limb and stood there at least two
minutes, without being detected.

F. H. Fowler (1903) writes:

The Arizona woodpecker (_Dryobates arizonae_) is, outside
of the alpine three-toed and pileated, the most interesting
member of the woodpecker family, that I have ever seen. So
far as I have noted, the species is never common, never
noisy, and never at rest. I have not found it except in
live-oak woods, and at Fort Huachuca; on a good field
day I used to see about six on an average. Not even the
chickadees are as active as this little woodpecker. He
will alight on the main trunk of the tree, or generally
one of the largest limbs, and the moment his claws are
fastened in the bark he begins an untiring search for
insects and grubs. He ascends rapidly in spirals picking
and prying away small pieces of bark in search of food;
when a promising limb is reached out he goes on it, often
on the lower side. The search over in one tree, he wastes
no time in looking around, but launches out, with barely a
glance to determine the course, in his undulating flight
to the next, there to repeat the performance. When closely
approached, he works around the tree without paying any
especial attention to the intruder, and when thoroughly
frightened he will take flight with as little warning as he
does when simply in search of food. While going up the tree
he gives, from time to time, a characteristic call, much
like that of the hairy woodpecker.

_Field marks._--The Arizona woodpecker should be easily recognized, as it is the only small woodpecker that has a uniformly brown, unmarked back and crown, and lower parts thickly spotted with black; the adult male has a red patch on the nape, and young birds of both sexes have more or less red in the crown, less in the female than in the male.

_Winter._--This woodpecker is a permanent resident in southern Arizona, moving down from the higher parts of the mountains to the lower levels in winter. Mr. Swarth (1904) says that “in the winter they seem to more particularly favor the large groves of live-oaks along the foot-hills and at the mouths of the canyons; scattering over the mountains and ascending to rather a higher elevation upon the advent of the breeding season.” W. E. D. Scott (1886) writes: “Rarely have I met with more than two in company, and a family, two parents and three young, were the most I ever saw associated together. But I frequently met in the fall a party composed of Arizona jays, California woodpeckers, various Titmice and Warblers, and a pair of Strickland’s [Arizona] woodpeckers. The birds I have met with them appear late in January or early in February, and are apparently already mated.”

DISTRIBUTION

_Range._--Southwestern New Mexico, southeastern Arizona, and western Mexico; nonmigratory.

The Arizona woodpecker is found =north= to southeastern Arizona (Canada del Oro and the Whetstone Mountains); and southwestern New Mexico (probably the Animas Mountains and the San Luis Mountains). =East= to southwestern New Mexico (San Luis Mountains); Chihuahua (Cajon Bonito, Colonia Garcia, Temosachic, and Apache); Durango (Metalotes and Arroyo del Buey); and Zacatecas (Sierra de Valparaiso). =South= to Zacatecas (Sierra de Valparaiso) and Jalisco (Nevada Volcanoe, Colima Volcanoe, Tonila, and San Marcos.) =West= to Jalisco (San Marcos and Bolanos); eastern Sinaloa (Sierra de Choix); central Sonora (La Chumata mine and Saric); and southeastern Arizona (Huachuca Mountains, Santa Rita Mountains; Rincon Mountains Pantano, and Canada del Oro).

The range as outlined is for the entire species, which has been divided into two geographic races, the true Arizona woodpecker (_D. a. arizonae_), occupying the northern part of the area south to northwestern Durango, and the Colima woodpecker (_D. a. fraterculus_), occupying the rest of the range in Mexico.

_Egg dates._--Arizona: 8 records, April 20 to May 16.

DRYOBATES ALBOLARVATUS ALBOLARVATUS (Cassin)

NORTHERN WHITE-HEADED WOODPECKER

PLATES 13, 14.

HABITS

The northern race of the white-headed woodpecker is found in the Cascade Mountains and the Sierra Nevada, from Washington to Kern County, Calif., and eastward into western Idaho and western Nevada.

It is a bird of the pine and fir forests in the mountains, ranging from 4,000 to 9,000 feet during the breeding season, but coming down to lower levels in winter. W. L. Dawson (1923) says: “This woodpecker is essentially a pine-loving species and is, therefore, nearly confined to the slopes of the Sierras and the Transition zones of the southern ranges. Only in winter does it appear at lower levels, and then rarely beyond the pale of the yellow pine. So close is this devotion of bird to tree that the woodpecker’s feathers are almost always smeared with pine pitch; and I have found eggs dotted with pitch and soiled to blackness by contact with the sitting bird.”

Clarence F. Smith writes to me that he found this woodpecker very common around a camp where he was located from June 25 to July 10, 1935, in Tuolumne County, Calif., in the Transition Zone at an elevation of about 4,000 feet. The camp was at one time a lumbering mill, and there was much dead standing timber nearby. Most of the trees were _Pinus ponderosa_ and _Pinus lambertiana_.

_Nesting._--The same observer says in his notes: “All the nests observed, except one in a _Quercus kelloggii_, were in dead standing stumps of the pines. The stumps were mostly some 12 to 15 feet in height, and the nests averaged about 8 feet above ground, with an approximate minimum of 6 feet. These nests may not represent a typical situation, as they were undoubtedly the ones that were most obvious to casual observation. Nests in higher locations would more easily escape notice. We had at least 8 nests within a half-mile radius of camp headquarters, and the birds were one of the commonest species in the vicinity. None of the nests opened contained any lining but chips of wood, and the cavities were about 14 inches in depth. None of the nest trees were less than 2 feet in diameter at the point where the nest was located. Many of the stumps had several holes in them, some of which had been nests in previous years, and some of which had been merely abortive attempts at drilling. The one nest in the oak, referred to above, was in a live tree with a decayed heart.”

Major Bendire (1895) writes:

Nidification usually begins about the middle of May and
continues through June. The sexes relieve each other in the
preparation of the nesting site, which is usually located
in a dead stub of a pine or fir; one that is partly decayed
seems to be preferred as it rarely excavates one in solid,
hard wood. The nesting sites are seldom situated over 15
feet from the ground, and sometimes as low as 2 feet. The
entrance hole is about 1½ inches wide, perfectly circular,
and just large enough to admit the bird; the inner cavity
gradually widens towards the bottom, and is usually from 8
to 12 inches deep, the eggs lying on a slight layer of fine
chips, in which they become well embedded as incubation
advances. Occasionally a rather peculiar site is selected.
Mr. Charles A. Allen found a nest of this species in a post
in one of the snow sheds on the Central Pacific Railroad,
between Blue Canyon and Emigrant Gap, about 40 feet from
the entrance of the shed, and some thirty trains passed
daily within a few feet of the nest, which contained six
eggs when found.

Milton P. Skinner sends me the following notes on nest building by this woodpecker: “On May 10, 1933, I found one at work on a hole in a stub of a tree, about 3 feet above ground. Although this was in the Sequoia National Park beside one of the most used paths, it was deepening the hole for a nest. Chips were scattered on the ground below. After pecking a while, the woodpecker would get into the hole and soon after back out again with a billful of chips. It then opened its bill and let them scatter to the ground; then back to work again. Although this was as public a place as could be found, and though the birds must frequently have been disturbed by the crowds of people and were within reach of hundreds of children, they succeeded in raising their brood of young. In spite of nesting so low, most of these birds are usually seen from 20 to 50 feet, and sometimes as high as 100 feet, above ground, working on the trees.”

Of ten nests found by Grinnell and Storer (1924) in the Yosemite region--

the lowest was located only 58 inches (measured) above
ground and the highest, 15 feet (estimated). * * * No nest
holes of this woodpecker were found in living conifers.
Nor, on the other hand, do the birds seek what is commonly
known as rotten wood, that is, wood too soft for the nest
cavity to be maintained against the incessant wear involved
in the birds’ passage back and forth, incident to the
rearing of a brood. The tree chosen must have been dead a
sufficient length of time for the pitch to have hardened or
to have descended to the base of the tree, and the outer
shell of the tree must still be hard and firm, whereas the
interior must have been softened to a moderate degree by
decay. These conditions are not to be met with in every
standing dead stub; hence the choice of a nest site becomes
a matter of rather fine discrimination.

They found plenty of evidence of this discrimination in the many unfinished nesting holes of varying depths that had been abandoned, often several in the same stub. “Some stubs are literally riddled with holes, these probably recording successive years of occupancy. One stub had at least 5 fully excavated holes besides 11 or more prospects. * * * We were led to conclude from all this that the White-headed Woodpecker is either notional or else very particular, in the selection of its home. Evidence points strongly to the birds excavating and occupying a new cavity each year, although one set of eggs was found in a hole which had been dug in earlier years.”

They made a number of careful measurements of four nests, at heights varying from about 5 feet to about 10 feet above ground; the internal dimensions varied somewhat, but the size of the entrance hole was “surprisingly constant”; in one case this hole was a perfect circle, 43 by 43 millimeters, and in another 37 by 37 millimeters; in the other two cases the entrance hole measured 47 millimeters in height and 42 in width; translated into inches this shows a variation in the two dimensions of from 1.45 to 1.85 inches, which does not seem to be “surprisingly constant.” The total depth of the cavity varied from 275 to 400 millimeters, or from about 10 to 15 inches.

They say further: “Two of the nest cavities we found were in such unusual sites as to call forth comment. One at Hazel Green was in a slanting upright limb on a prostrate dead black oak trunk lying in a grassy meadow, fully 150 feet from the margin of the forest. The hole was excavated on the lower side of the stub. The other nest was at Tamarack Flat, in the butt end of an old log, lifted above the ground when the tree fell over a granite outcrop. This hole was about 7½ feet above the ground, and as with the other there were piles of chips immediately beneath it.”

Grinnell, Dixon, and Linsdale (1930) mention a nest they found in the Lassen Peak region that was “four meters up in the trunk of a dead-topped aspen.” Bendire (1895) mentions a nest found near Camp Harney, Oreg., that was about 25 feet from the ground in a dead limb of a pine; this nest seems to be at about the limit as to height above ground. A set in my collection was taken from a nest 10 feet up in a dead aspen.

_Eggs._--The white-headed woodpecker lays three to seven eggs, four being the commonest number, and five rather often. These vary in shape from ovate to short-ovate. They are pure white and moderately or quite glossy. Grinnell and Storer (1924) say: “The eggs in one set had a wrinkled appearance at the smaller end as though that end had been compressed before the shells had hardened. Eggs which are advanced in incubation are apt to be soiled by pitch; this is doubtless brought in by the parent birds on their bills, feet, or plumage.” Sometimes the eggs show tiny black dots, or are profusely smeared with black from the same cause. The measurements of 50 eggs average 24.26 by 18.11 millimeters; the eggs showing the four extremes measure =26.40= by 18.29, 25.40 by =19.50=, =21.84= by 17.78, and 22.86 by =16.76= millimeters.

_Young._--Incubation is said to last for 14 days and to be shared by both sexes. Both parents also assist in the care and feeding of the young. Clarence F. Smith tells me that “the female at one nest made trips about twice as frequently as the male; her visits were about two minutes apart, while the visits of the male were about five minutes.” Grinnell, Dixon, and Linsdale (1930) write:

On July 1, the young woodpeckers, by this time half-grown,
were being fed by the parents, mostly by the female. Food
was brought at intervals averaging fifteen minutes each.
The birds foraged at distances up to a quarter of a mile
away from the nest. The female carried away the feces.

On July 11 the female seemed to be coaxing the young from
this nest. When the young woodpeckers stuck their heads out
of the cavity, the parent would move away from the entrance
and call, although it remained on the tree trunk. When
a person shook the stub two of the young birds flew out
and went thirty meters before coming to the ground. When
placed on a tree trunk the birds could move freely upward
or downward. Within a few minutes one of the young birds
could fly so well that it successfully evaded capture by
the observer.

_Plumages._--As with other woodpeckers, the young are hatched naked and blind, but the juvenal plumage is acquired before the young bird leaves the nest. The juvenal plumage is much like that of the adult but duller, and the bill is shorter and weaker; the contour plumage is softer and looser; the lower parts are brownish black instead of clear black, and the back is only a little darker; the white in the primaries is more restricted. In the young male, the posterior half of the crown is largely “vermilion” or “salmon orange”; these reddish colors are much reduced or entirely absent in the young female. Ridgway (1914) says that the feathers of the hind neck and underparts are sometimes, perhaps on younger birds than I have seen, “indistinctly and narrowly margined at tip with grayish, and the hindneck sometimes indistinctly spotted with whitish.” By the middle of September this juvenal plumage, including the wings and tail, has been replaced by the first winter plumage, which is like that of the adult, except for somewhat less white in the primaries. Adults have a complete annual molt, which begins in July and is generally completed before the end of September.

_Food._--The white-headed woodpecker forages for its food mainly, if not entirely, on the trunks and branches of coniferous trees, living or dead. Mr. Skinner writes to me that he has seen it feeding on the trunks of sequoias, sugar pines, and Douglas firs, searching most diligently and thoroughly in the crevices in the bark for insects and their eggs; it generally begins low down on the tree and progresses upward, working pretty well up to the top of the tree before flying off; occasionally, one has worked horizontally around a tree trunk, but not downward. Dr. J. C. Merrill (1888) describes its method of feeding very well, as follows:

So far as I have observed, and during the winter I watched
it carefully, its principal supply of food is obtained
in the bark, most of the pines having a very rough bark,
scaly and deeply fissured. The bird uses its bill as
a crowbar rather than as a hammer or chisel, _prying_
off the successive scales and layers of bark in a very
characteristic way. This explains the fact of its being
such a quiet worker, and as would be expected it is most
often seen near the base of the tree where the bark is
thickest and roughest.

It must destroy immense numbers of Scolytidae, whose larvae
tunnel the bark so extensively, and of other insects that
crawl beneath the scales of bark for shelter during winter.
I have several times imitated the work of this bird by
prying off the successive layers of bark, and have been
astonished at the great numbers of insects, and especially
of spiders, so exposed.

Prof. F. E. L. Beal (1911) examined only 14 stomachs, but says that “half of the animal food of the white-headed woodpecker (_Xenopicus albolarvatus_) is ants, but the most pronounced characteristic of this bird is its fondness for the seeds of pines, which constitute more than half of the food.”

Grinnell and Storer (1924) say: “Stomachs of two adult birds, obtained at Merced Grove Big Trees on June 10, 1915, and at East Fork of Indian Cañon, June 24, 1915, both held ants, some of which were large carpenter ants. The stomach of one of the young birds from the nest mentioned above contained remains of 2 large spiders, a large ant, 2 boring beetles, and a whole fly larva.”

Major Bendire (1895) quotes Rollo H. Beck as saying: “I noticed one of these birds on some fallen logs near the road, busily engaged in catching spiders, searching for grubs, and frequently flying after passing insects, catching them in mid-air in the manner of the California Woodpecker.”

_Behavior._--Dr. Merrill (1888) writes: “Though not shy, and with care generally approachable to within a short distance, it is watchful and suspicious, and seems to know very well what is going on even if it does not see fit to fly away, though it is more apt to do this than to dodge around the trunk. The flight is direct, and rather slow and heavy.” Dr. Merrill noted that the skull of the white-headed woodpecker is “noticeably less hard and dense” than the skulls of other woodpeckers; this is probably due to the fact that its method of feeding requires less heavy drilling into hard wood.

Mrs. Florence M. Bailey (1902) says: “_Xenopicus_ works with apparent indifference on trunks or branches. Like the Nuttall woodpecker he often lights upside down. In hunting over the bark he easily backs down the trunk, or if he takes the notion will fly, or perhaps drop backwards, a foot or so. He will also light sidewise on a branch and grasp the limb with his tail as if afraid of falling off. It is interesting to see him explore cracks in the bark. Standing on the edge he pokes his head into the dark cavern, turning it from one side to the other inquiringly.”

Grinnell and Storer (1924) write:

At Tamarack Flat, on May 26, 1919, a female white-headed
woodpecker was seen to flush from her nest about ten feet
above ground in a dead pine stub. Tapping by one of us on
a nearby hole had caused her to leave, but she returned
to the vicinity almost immediately. Then, for fully 25
minutes, while the observer remained within watching
distance the bird foraged, preened, and flew about from one
to another of the circle of 8 or 10 trees within a 50-foot
radius of the nest, but always kept the nest tree in her
sight. About every 5 minutes she would fly to the nest. In
approaching it, she would swoop below its level and then
glide up to the site with decreasing speed so as to end
her flight with little or no momentum. Then, having gained
claw-hold, she would poke the fore part of her body into
the hole, withdraw it at once and repeat this performance
four or five times before flying away again. Finally, after
fully half an hour had elapsed, and her suspicions had been
allayed, she went in, to remain. During this entire time
the male kept out of sight and was heard only twice.

Van Rossem and Pierce (1915) noted its manner of drinking, thus: “White-headed woodpeckers were often observed to drink at a small stream near our camp at Bear Lake, where a pine sapling grew from the edge of a small pool. On this sapling the birds would alight, usually about three feet from the base, ‘hitch’ quickly backwards down the trunk to the water, and, leaning sharply to one side, drink by quick, nervous dips.”

Another method of drinking is described by Grinnell, Dixon, and Linsdale (1930), as follows: “In mid-afternoon one flew down from a yellow pine to some shallow, running water in an open roadside near Mineral. It alighted in a horizontal position on the ground and dipped its bill into the water six times. After each dip the bird raised its bill skyward at an angle of fully eighty degrees from the horizontal. After drinking, the bird flew to a prostrate log, and foraged horizontally along its lower curvature.”

Some observers seem to think that the white-headed woodpecker rarely, if ever, drums on tree trunks, but seeks its food more quietly; but Alexander Sprunt, Jr., tells me that the birds he saw in Oregon “drummed and beat upon the tree trunks and telephone poles at the roadside, exactly as any other woodpecker.” Clarence F. Smith writes to me that “one male bird was a regular overnight guest, hanging to the ridgepole of our cabin, outside the wall, just beneath the eaves. He never made any attempt to drill the wood there.”

_Voice._--Grinnell and Storer (1924) say that “the usual call note of this woodpecker is a single _wiek_, but when excited, the female calls _cheep-eep-eep-eep_, very fast, and repeats the call every few seconds. The male, under similar circumstances calls _yip, yip, yip, yip_, in a much shriller tone, but in slower time.” Mr. Dawson (1923) once heard “a double or treble call-note, _chick-up_ or _chick-it-up_, which reminded me somewhat of the Cabanis’s cry.” Major Bendire (1895) heard it utter “a sharp, clear _witt-witt_” as it passed from one tree to another; he considered it a rather silent bird.

_Field marks._--The white-headed woodpecker could hardly be mistaken for any other bird. It is the only woodpecker with a wholly black body and a wholly white head; while perched it shows a long white stripe in the wing, and while flying a large white patch in the wing is conspicuous; the narrow red band on the nape is not conspicuous and can be seen only at short range and only in the adult male; young birds show more or less red in the crown. One would think that such a strikingly marked bird would be very conspicuous, but such is not the case; its coloration is, in fact, somewhat concealing in its chosen environment; its quiet behavior helps to make it less obvious. For example, Dr. Merrill (1888) writes: “On most of the pines in this vicinity there are many short stubs of small broken branches projecting an inch or two from the main trunk. When the sun is shining these projections are lighted up in such a manner as to appear quite white at a little distance, and they often cast a shadow exactly resembling the black body of the bird. In winter when a little snow has lodged on these stubs the resemblance is even greater, and almost daily I was misled by this deceptive appearance, either mistaking the stub for a bird or the reverse.”

Furthermore, Grinnell, Dixon, and Linsdale (1930) state that “it was further observed that in usual pose, either when foraging or when in digging or inspecting a nest hole, the whole back of a bird (either sex) appeared to a nearby observer solidly black, clear to the top of the head. The white showed only as a very narrow rim or border anteriorly around the black of the head. * * * At the same time the concealing black of the bird’s dorsal surface must cover all of the area of the bird exposed to the view of the potentially inimical observer at more or less distance.”

And again, Mrs. Bailey (1902) says:

Impossible as it would seem at first sight, I have found
that the snow-white head often serves the bird as a
disguise. It is the disguise of color pattern, for the
black body seen against a tree trunk becomes one of the
black streaks or shadows of the bark, and the white head
is cut off as a detached white spot without bird-like
suggestions. On the other hand, when the bird is exploring
the light-barked young Shasta firs or gray, barkless tracts
of old trees, the white of the head tones in with the gray
and is lost, the headless back again becoming only a shadow
or scar. But the most surprising thing of all is to see the
sun streaming full on the white head and find that the bird
form is lost. The white in this case is so glaring that it
fills the eye and carries it over to the light streaks on
the bark, making the black sink away as insignificant.

The activities of this and other woodpeckers play an important role in the welfare of the forests and the lives of the little furred and feathered denizens of the woods. It is a well-known fact that woodpeckers are most useful in guarding the living trees and destroying the insect pests that injure them; but Grinnell and Storer (1924) have called our attention to the fact that woodpeckers in general, and the white-headed woodpecker in particular, contribute, by their excessive drilling of nest holes, “rather directly toward bringing down the standing dead timber.” They continue:

Drilling by woodpeckers results in an increase in the
number of entrances through which insects may get at
the heart wood of a tree and thus hasten its ultimate
disintegration. Water, also, is thus afforded an easier
entrance and this hastens decay. Eventually each and every
tree must yield its place in the forest to seedlings. The
woodpeckers hasten this process of replacement, once the
tree is dead.

Many of the wood-inhabiting animals depend upon this
woodpecker to furnish them convenient nest holes
or retreats. We have found mountain chickadees and
slender-billed nuthatches incubating their own eggs
in holes drilled in earlier years by the white-headed
woodpecker; a Sierra flying squirrel was found occupying an
old white-head’s hole. Probably, tree-dwelling chipmunks
and perhaps California pigmy owls also occupy holes of this
woodpecker.

DISTRIBUTION

_Range._--Pacific coast of the United States; occurring rarely in southern British Columbia; nonmigratory.

The range of the white-headed woodpecker extends =north= to Washington (Methow River and probably Fort Colville); and northern Idaho (Fort Sherman). =East= to western Idaho (Fort Sherman and Grangeville); eastern Oregon (Hurricane Creek, Powder River Mountains, Anthony, and Camp Harney); western Nevada (Carson); and eastern California (Bijou, Yosemite Valley, Pyramid Peak, San Bernardino Mountains, and Cuyamaca Mountains). =South= to southern California (Cuyamaca Mountains and Mount Pinos). =West= to the western slopes of the Sierra Nevadas, Calif. (Mount Pinos, Bear Valley, Fyffe, Butte Lake, and Mount Shasta); western Oregon (Pinehurst, Foley Creek, and The Dalles); and western Washington (Kalama, Cle Elum, and Methow River).

The species has been separated into two subspecies, the northern white-headed woodpecker (_Dryobates a. albolarvatus_), occupying most of the range south to the southern end of the Sierra Nevadas, and the southern white-headed woodpecker (_D. a. gravirostris_), found in the mountain ranges of southern California.

_Casual records._--A specimen collected near Point Bonita, Marin County, Calif., on July 20, 1932, is the only coastal record in that State. There is, however, an old record for Grays Harbor, Wash. (previous to 1892), which cannot now be confirmed.

In the Provincial Museum at Victoria, British Columbia, there is an unlabeled specimen said to have been collected in the Similkameen Valley. Two have been collected at Okanagan, British Columbia, one on December 20, 1911, and the other on January 24, 1914.

_Egg dates._--California: 53 records, April 24 to June 16; 27 records,
May 22 to June 7, indicating the height of the season.

DRYOBATES ALBOLARVATUS GRAVIROSTRIS (Grinnell)

SOUTHERN WHITE-HEADED WOODPECKER

HABITS

Dr. Joseph Grinnell (1902), in describing and naming the white-headed woodpecker of the mountain ranges of southern California, gave as its characters: “Similar to _Xenopicus albolarvatus_ but bill much heavier, and size in general slightly greater.” He named it as a distinct species, on the theory that “the material at hand does not justify subspecific treatment of these two forms. Geographical continuity of ranges possibly exists; but it seems quite as likely that there is a broad hiatus in the vicinity of Tehachapi Pass, whence I can find no record of the white-headed woodpecker.”

The range of this form includes the San Gabriel, San Bernardino, San Jacinto, Santa Rosa, and Cuyamaca Mountains in southern California. Dr. Grinnell (1908) found this woodpecker rather scarce in the San Bernardino Mountains, and says: “They were seen only in the Transition zone, none being observed above the fir belt, and but very few down into pure yellow pine tracts. In the vicinity of Fish creek, 6,500 feet, a few pairs were breeding in June. On July 5, 1905, I found a nesting hole seven feet up in a dead pine stub, which contained four half-fledged young. We did not see the species anywhere higher than 8,000 feet, except on the south slope of Sugarloaf, where on July 11, 1906, one was seen among the silver firs at about 9,000 feet altitude. About Bluff lake they were more common than anywhere else, and a few were seen on the northern slopes of Sugarloaf at about 8,000 feet, in August.”

W. L. Dawson (1923) writes: “In the San Jacinto Mountains, where these white-heads outnumber all other woodpeckers combined, our attention was drawn, on the 6th day of June, by a male who tittered anxiously as we stumbled along the rough trail. We camped on the prospect immediately, but it took a full hour to trace the ‘damage’ to a hole fifty feet up in a yellow pine stub, which was three feet through at the base. * * *

“We found a clean-cut round hole, one and a half inches in diameter, which gave admission to a cavity ten inches deep, and which had for its outer wall only the thick bark of the tree.”

Frank Stephens wrote to Major Bendire (1895): “_Xenopicus albolarvatus_ is a resident of the pine regions of southern California, but is not common excepting possibly in a few localities. I have never observed it below the pines. I have taken incubating birds in June in the Cuyamaca Mountains at altitudes of about 7,000 feet. The nesting sites here were in very large dead pine trees and inaccessible.”

This woodpecker seems to show a tendency to nest, at least occasionally, at greater heights above ground than its northern relative, but otherwise its habits seem to be very similar.

The eggs are similar to those of the northern race. The measurements of 20 eggs average 24.67 by 18.60 millimeters; the eggs showing the four extremes measure =26.70= by 19.50, 25.60 by =19.70=, and =22.62= by =16.67= millimeters.

PICOÏDES ARCTICUS (Swainson)

ARCTIC THREE-TOED WOODPECKER

PLATES 15, 16

HABITS

Although not found in the strictly Arctic, treeless regions, this bird is probably well named, for its range as a whole averages farther north than that of any other woodpecker except _P. tridactylus_. It is a bird of the boreal forests of spruces and firs, ranging as far north in Alaska and northern Canada as these trees grow, and extending its range southward throughout the Canadian Zone into the Northern United States and farther southward in some of the higher mountain ranges.

In the eastern portion of its range this woodpecker seems to prefer the dense virgin forests of spruces and balsam fir, but it nests mainly in the more open windfalls or burned-over clearings where there are plenty of dead, standing trees in which to excavate its nest. In New York State, near the southern limit of its breeding range, a typical locality is thus described by Laurence Achilles (1906): “At three thousand feet or more above the sea, in the denser spruce and balsam forests of the Adirondacks, the Arctic three-toed woodpecker is fairly common. * * *

“The trees near the nest were chiefly spruces, with a few balsams and birches scattered among them. The birds had selected a rather open place for their nesting-site, as, within a radius of ten yards from their nest, there were several windfalls and dead spruces. The ground was carpeted with moss, while linnea, clintonia, wood-sorrel and bunchberry were blossoming in profusion near the base of the tree.”

In the Midwestern States and Provinces, the Arctic three-toed shows a decided preference for tamarack swamps, especially where these have been burned over, leaving a few dead or dying trees still standing; these trees not only furnish an abundant food supply but offer many convenient nesting sites. Into such attractive habitats these birds sometimes congregate to form small breeding colonies.

The Weydemeyers (1928) say that in northwestern Montana this woodpecker “is found most frequently in Transition zone woods that have been logged or burned over. In virgin forests it occurs sparingly in yellow pine woods at low elevations; more commonly in mixed broad-leaf and conifer, and Douglas fir, associations; and rarely in alpine fir and lodgepole pine woods of the higher mountains, in the Canadian zone. Its favorite feeding trees are Douglas fir and western larch.”

_Nesting._--Philipp and Bowdish (1919) found four or five nests of the Arctic three-toed woodpecker in Northumberland County, New Brunswick, in May and June 1917. Most of the nests were in living balsam firs with dead hearts, but one was “in a dead maple stub, near the edge of a large burnt barren, and a short distance from the edge of mixed woods.” This was “at a height of about ten feet. The cavity measured 10½ inches from the lower edge of entrance to bottom. The entrance measured 1⅝ inches in height and 1¾ inches in width.” They say that--

apparently nest sites are selected indiscriminately, in
dead stubs in open cleared ground or burnt barrens, and
in the woods, where nests are often in dead-hearted live
trees. The birds have a remarkably strong attachment for
their nests, as evidenced by re-laying in nest holes
from which eggs had been removed, and their disregard of
the immediate presence of intruders. The male evidently
performs his share of the work of incubation, as well as
care of young. New nest holes are apparently dug each year,
and these may not be in the immediate vicinity of nests of
the previous year. The site selected tends to be low, only
one nest having been noted at a height of over ten feet,
while one, as noted, was as low as two feet. Entrances to
nest holes are strongly beveled at the lower edge, forming
a sort of “door-step,” and more or less at sides and even
top. While this is true in some cases with the Northern
Hairy and some other woodpecker excavations which we have
examined, it has not proved so frequent or pronounced. With
experience, one can usually identify the nest hole of this
species with comparative certainty, by this one feature.

Dr. Harrison F. Lewis watched a pair of these woodpeckers excavating their nesting hole on May 27, 1936, in some second-growth woods, chiefly spruce and fir, in Saguenay County, Quebec; he says in his notes: “The Arctic three-toed woodpeckers had a partly excavated nest cavity at a height of about 14 feet on the northwest side of a dead birch stub in a clearing. The stub was about 20 feet high and 1 foot in diameter and stood about 10 feet from the border of the clearing. The nest cavity was guarded almost continually by one bird of the pair. The bird on guard clung to the lower edge of the opening of this cavity. Nine other woodpecker-made openings, many of them only partly completed, were to be seen in the same stub.

“I watched the three-toed woodpeckers, from partial concealment near at hand, for an hour and 25 minutes. Each one of them would spend a period of 15 to 20 minutes at their nest cavity, then be relieved by the other. The periods spent at the cavity by the male were somewhat longer than those spent there by the female. While the male was at the cavity, he spent much of his time in excavating, with only his tail and the region of his rump projecting from the opening, but at intervals of a few seconds he would withdraw his body and head from the cavity and look about him. When he was excavating, very little noise could be heard. He spent some time in throwing out chips and some time in resting. When the female was at the cavity, she did very little excavating, so little that it seemed to be a mere gesture. On one occasion, after she had been clinging to the edge of the opening for 10 minutes, she drummed repeatedly, but not loudly, on the outside of the stub beside the opening. I wondered if she were signaling to the male to come to relieve her in guarding the cavity. After 5 minutes of such intermittent drumming, she was relieved at the opening by the male.”

Mr. Achilles (1906) describes the nest he found in the Adirondacks as follows:

The hole, which was in a spruce tree, faced north by
northeast, and was twenty-seven feet one inch from the
ground. The spruce retained all its branches and some
twigs, although it had been dead for some time.

The following dimensions of the hole were taken after the
young had left their nest. The entrance to the hole was
two inches wide and one and five-eighths inches high. From
the outside of the hole, straight through over the top of
the nest to the back of the hole, the measurement was five
and three-fourths inches. The outside shell, including the
bark, was one and three-fourths inches thick. The diameter
of the nest opening was three and one-fourth inches, while
the diameter of the hole on the inside at the bottom of the
shaft, was four and five-eighths inches. The depth of the
hole was nine and one-eighth inches.

Dr. C. Hart Merriam sent Major Bendire (1895) some notes on two nests that he found in the Adirondacks, as follows:

The water of Seventh Lake, Fulton Chain, had been raised by
a dam at the foot of Sixth Lake, flooding a considerable
area along the inlet, and the trees killed by the overflow
stood in about 6 feet of water. In 1883 the place was
first visited by me, May 27. Both species of Three-toed
Woodpeckers (_Picoides americanus_ and _arcticus_) were
tolerably common, and one new nest of each was found.
That of _P. arcticus_ contained one fresh egg. The nest
was 10 inches deep, and the opening within 5 feet of the
surface of the water. It was in a dead spruce, 10 inches
in diameter. * * * The place was next visited, June 2, but
the date proved still too early. Several unfinished nests
of _P. americanus_ were found, and one completed nest with
four fresh eggs of _P. arcticus_. Like the one found on my
first visit, it was in a dead spruce and about 5 feet above
the water. The nest was 11 inches deep and the orifice 1¾
inches in diameter.

J. H. Fleming (1901) says that the Arctic three-toed woodpecker is “a common resident in Parry Sound, rarer in Muskoka. This Woodpecker has a habit of sometimes nesting in colonies. I saw the nests of such a colony near Sand Lake in 1896; there were six or seven nests, each cut into the trunk of a living cedar, just below the first branch, and usually eight or ten feet from the ground. The cedars were in a dense forest, overlooking a small stream that empties into Sand Lake.”

Macoun (1909) reports, on the authority of Spreadborough, that “a pair nested in a telegraph pole quite near Cache lake station of the Parry Sound railway.” Major Bendire (1895) writes:

On May 10, 1883, while en route from Fort Klamath to
Linkville, Oregon, and only a few miles from the latter
place, just where the pine timber ended and the sagebrush
commenced, I found a male busily at work on a pine stump,
only about 2½ feet high and about 18 inches in diameter,
standing within a few feet of the road, and close to a
charcoal burner’s camp, in quite an open and exposed
situation, nearly all the timber in the vicinity having
been cut down. The stump was solid, full of pitch, and
showed no signs of decay; the entrance hole was about 1½
inches in diameter and 8 inches from the top. The cavity,
when first examined, was only about 2 inches deep, and
on my return, two days later, it had reached a depth of
4 inches: the female was then at work. To make sure of a
full set of eggs, I waited until the 25th. The cavity then
was found to be 18 inches deep, and was gradually enlarged
toward the bottom. The four eggs it contained had been
incubated about four days. The female was on the nest, and
uttered a hissing sound as she left it, and might easily
have been caught, as she remained in the hole until the
stump was struck with a hatchet. The sides of the cavity
were quite smooth, and the eggs were partly embedded in a
slight layer of pine chips. The locality where this nest
was found was near the top of a low divide, not over 4,100
feet in altitude.

Dr. Thomas S. Roberts (1932) calls attention to an interesting feature in the nesting habits of this woodpecker, as observed in two nestings that he saw in Minnesota; he says of the two nests:

The nesting-hole was in a live jack-pine on the edge of a
tamarack and spruce swamp, only twenty feet from a traveled
road and close by a log house used as a store. The entrance
faced south and was twelve feet from the ground, at which
point the tree was seven inches in diameter. The outer bark
of the tree had been chipped off for a distance of twelve
to fifteen inches above and below the hole and half-way
around the tree, thus leaving a large, irregular, whitish
area. * * *

Another nest, found the same season, was also in a live
evergreen tree and the outer bark had been similarly
stripped from around the entrance, making a conspicuous,
white patch with the dark nesting-hole in the center. Can
this be a direction mark for the returning bird among the
dark tree trunks around?

As to the height from the ground, P. B. Philipp writes to me that of 26 nesting holes examined by him in New Brunswick two were 15 feet, two 12 feet, three 10 feet, one 8 feet, two 6 feet, two 5 feet, four 4 feet, six 3 feet, and four only 2 feet above ground.

Although the Arctic three-toed woodpecker usually nests at no great height above ground, there are a few exceptions to this rule, mainly in the western portion of its range. Grinnell and Storer (1924) record a nest seen in the Yosemite region that was 50 feet above ground in a dead lodgepole pine. Harry S. Swarth (1924) found, in the Skeena River region, the highest nest of which I can find any record; he says: “A nest of the Arctic three-toed woodpecker was found in Kispiox Valley. It was placed in a dead and charred Engelmann spruce, in a strip of spruce woods bordering a muskeg otherwise surrounded by poplar forest. The nest hole was eighty feet from the ground. It was two and one-half inches in diameter and one foot deep, drilled through an outer sheath of sound, hard wood, and downward through soft, rotten ‘punk.’”

_Eggs._--The number of eggs laid by the Arctic three-toed woodpecker varies from two to six, four being the commonest number. These vary from ovate to elliptical-ovate, the former shape prevailing. The shell is dull or only slightly glossy and is pure white. The measurements of 39 eggs average 21.32 by 18.94 millimeters; the eggs showing the four extremes measure =25.9= by 18.7, 25.1 by =20.2=, and =22.35= by =17.53= millimeters.

_Young._--The period of incubation is about 14 days; both sexes assist in this and in the care of the young. Only one brood is raised in a season, but if the eggs are taken, a second set will be laid, often in the same nest.

Mr. Achilles (1906) watched a nest containing young for 24 consecutive hours, he and a companion taking turns at the vigil and sleeping alternately within ten yards of the tree; he writes:

The parents, when feeding their young, usually alighted
within a space of three feet below the hole, and never
directly at its entrance. They would pause here for a
moment as though fearing they were observed by someone.
Then they would hop up to the hole and look in, anywhere
from two up to six times, as if accustoming their eyes to
the darkness. Once in a while grubs could be seen in their
bills, but, from the actions of the birds when feeding
their young, they appeared to be regurgitating. During
twenty-four hours the female fed the young thirty times,
and the male twenty-nine times.

As it grew dusk, the young gradually grew quieter, and
their little “peep-peep-peep” greatly resembled those of
chicks when crawling beneath their mother’s wings. From two
o’clock in the afternoon till seven o’clock that evening,
two minutes was the longest period during which the young
did not utter a single “peep.” From seven P. M. until
two minutes after four the next morning, the young birds
ceased this continuous chattering. The mother was the last
to feed them at night, the time being seventeen minutes
after seven; but the male was up first in the morning.
At four-fifteen in the morning, the young uttered a few
sleepy “peeps,” and the male alighted three feet below the
hole at four-sixteen. The young birds heard him alight and
immediately commenced to chatter. The male hopped up to the
hole, looked in twice, and then fed them. The young birds’
bills were seen, indicating that they were very hungry,
and were hanging on to the inner wall of the nest near the
entrance. Soon after this their hunger was appeased, their
bills were seen no more, and the parents had to go almost
into the hole to feed them.

_Plumages._--The nestlings are naked and blind at first, but the juvenal plumage is acquired before the young leave the nest. In the juvenal plumage, the young male is similar to the adult male, but the yellow crown patch is smaller and not so sharply defined; the upper parts are duller, browner black, lacking the glossy, bluish edgings; the breast is tinged with dull buffy white; and the flanks are more heavily and less distinctly barred or spotted with dull black. The young female is similar to the young male, but there is no distinct yellow patch on the crown, only scattering yellow feathers in varying amounts, often few or none at all. This plumage is worn through the summer and early fall; the first winter plumage, which is practically indistinguishable from that of the adult, is apparently not fully acquired until November or December. Adults have one complete annual molt, beginning in August.

_Food._--More than three-quarters of the food of both species of three-toed woodpeckers consists of the larvae of wood-boring beetles, mainly Cerambycidae and Buprestidae. Referring to the former, Prof. F. E. L. Beal (1911) says:

Stomachs containing 15 to 20 of these grubs are very
common, and one held 34. Probably the stomach is filled
several times each day, and it does not seem unreasonable
to assume that a bird will eat 50 of these insects every 24
hours for 6 months and at least 25 daily for the other half
of the year. At this rate one bird will annually destroy
13,675 of these destructive grubs. * * *

Probably there are not many other agencies more destructive
to timber than this family of beetles. Nor is timber safe
even after it has been cut. Logs lying in the mill yard or
forest may be ruined in a single season if these creatures
are not prevented from depositing their eggs. * * * A very
efficient check upon the undue increase of these insects
is found in the woodpeckers, especially the two species of
Picoides.

Weevils and other beetles and some ants are eaten, as well as a few other insects and spiders. Vegetable food, wild fruits, mast, and cambium amount to less than 12 percent of the food.

While with us, in southern New England, in winter, this woodpecker shows a decided preference for dead white pine trees (_Pinus strobus_), especially those that have been killed by fire or have been dead long enough for the bark to have partially peeled off. An isolated tree or a group of trees of this type may be visited day after day by one of these woodpeckers, during its stay, with such regularity that many an observer, who has never seen an Arctic three-toed woodpecker, may feel reasonably sure of finding one in such a place, if it has been previously seen there. Its persistent work on such a tree is well described by E. H. Forbush (1927) as follows:

This species very often begins to work on the trunk near
the foot of a tree; it sounds the bark with direct blows,
and then, turning its head from side to side, strikes its
beak slantingly into and under the bark, and flakes it off.
It often works long on the same tree and barks the whole
trunk in time, only occasionally working on the branches.
Thus it exposes channels of bark-beetles and the holes made
by borers. When the bird remains motionless, it is well
concealed against the blackened bark of the burnt trees.
It seems deliberate in its movements and appears to do its
work thoroughly, as it often remains five to ten minutes
on the same spot and then shifts only a little distance.
In early autumn, while the grubs are still at work on the
tree, it lays its head against the tree, at times, turning
it first to one side and then to the other as if listening.

Grinnell, Dixon, and Linsdale (1930) write of the feeding habits of this woodpecker in the Lassen Peak region:

One of these woodpeckers was watched as it moved slowly
up a tree trunk. It stopped to knock off a piece of bark
with a sidewise (glancing) blow of the heavy bill. This
was repeated several times. Then the bird began to drill
in earnest and the tapping could be heard by a person
more than thirty meters distant. The blows were delivered
rapidly, about two per second. Between three and five
minutes were required to bore through the bark, in this
instance twenty millimeters thick. Then after a few moments
of probing the bill was withdrawn and was seen to hold a
white larva which was quickly eaten. * * *

On one tree thirty-five centimeters in diameter an area of
bark thirty by sixty centimeters was punctured completely
through by twenty-two holes each leading to the tunnel
of a wood-borer. * * * The holes were twelve by twelve
millimeters across by twenty deep. It appeared to the
observer * * * that many of the still living trees in that
locality had been saved from complete destruction by the
insects, by the activity of this woodpecker.