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.