for the reception of acorns, many holes are probably made
which are never used, holes are made at seasons of the year
when there are no acorns to store, and large numbers of
perfectly serviceable holes seem to be abandoned even in
localities where both birds and acorns are abundant, and
new holes are being made.
As to the storing business itself: While this is
of distinct service to the food necessities of the
woodpeckers, the instinct sometimes goes wrong to the
extent of storing pebbles instead of acorns, thus defeating
entirely the purpose of the instinct. Again, large numbers
of acorns are sometimes stored, the use of which is so long
delayed that the acorns become wholly or largely unfit
for food, and this in places where the bird population
seems normal. Finally, acorns are sometimes stored in such
fashion as to make them easy prey for marauding rodents,
when with some definite foresight and a little more work
such exposure could easily be largely avoided.
In his second paper (1922), after further observations, he states[1]:
My previous surmise that the birds are more interested in
the grubs contained in the acorns than in the acorn meats
has not been substantiated. What I could make out while
in camp among them, by watching them gather and eat their
breakfasts, was to the effect that good uninhabited acorns
were chiefly used. Again and again birds were seen to pick
nuts from the top-most branches of the black oak, fly
with them in their beaks to some approximately horizontal
surface of a large limb on a pine or another oak, make
the surface aid them somehow (I never could see exactly
how, as the “breakfast tables” were, of course, all on the
upper surfaces of the limbs, and too high for my vision)
in breaking and tearing open the nuts. Apparently cracks
and chinks in the table top serve as holders for the acorns
while they are being opened and eaten. This is indicated
by the fact that dead and partly decayed trees or parts of
trees were mostly used. I saw no indication of the feet
being used in handling the nuts. The litter on the ground
under the dining trees, consisting of shell fragments
and lost bits of meat, indicated grubless nuts almost
entirely. This result as to the use of mast is in agreement
with Beal’s examination of the stomach contents of our
woodpecker.
Charles W. Michael (1926), in the Yosemite Valley, made the interesting
discovery that the California woodpecker has been known to learn by
experience and to show some intelligence in its acorn storing. For a
number of years when acorns were abundant no extensive storing was
done, yet the woodpeckers lived in the valley all winter. Then came a
lean year, with no acorn crop, when no storing _could_ be done; and
that winter the woodpeckers were forced to leave the valley for lack
of food. The following year there was a bountiful crop of acorns, and
the woodpeckers, having learned by experience, were busy filling up
their storehouses. “From the above observations,” he says, “one might
conclude that an abundance of acorns is not directly responsible for
prodigious storing. In a land of plenty the necessity of laying aside
stores for future consumption is obviated. It is the barren years that
teach the value of thrift. Intelligence plus experience may well have
been the cause of the excessive storing of this year. A few of the more
intelligent woodpeckers that were forced last winter to abandon the
valley for lack of food are now preparing against the next lean year.”
Claude Gignoux (1921) reports finding almonds stored in the bark of an
oak tree on a ranch near Marysville, Calif., as well as in the side of
a barn.
Dawson (1923) says: “A regrettable taste for fruit is occasionally
cultivated, but this has not reached economic proportions, save in the
case of almonds. Almond orchards thrive best at a very considerable
distance from oak groves.”
Although acorns, almonds, walnuts, and pecans constitute nearly 53
percent of its food, and much more than that in fall and winter, the
California woodpecker eats quite a variety of other food at different
seasons. Prof. F. E. L. Beal (1910) examined the contents of 75
stomachs, which contained “22.43 percent of animal matter to 77.57
percent of vegetable.” Bendire (1895) says: “During the spring and
summer its food consists, to a great extent, of insects, including
grasshoppers, ants, beetles, and different species of flies, varied
occasionally with fruit, such as cherries, which are carried off whole,
apples, figs, and also berries and green corn.”
Mr. Skinner says in his notes: “At times this bird feeds very much
like an eastern red-headed woodpecker. On May 9, 1933, one was seen on
the trunk of an oak, only 4 feet above ground, making flycatcherlike
sallies up under the foliage of the oak. And many times thereafter I
saw the birds operating similarly within the foliage itself. In some
instances I have seen these woodpeckers dart out from high up in tall
yellow pines after passing insects, then gliding back on set wings.
Sometimes they do this from tall electric poles, at times going out as
much as 50 feet. Since there was every reason to suppose that the bird
saw the insect before it started, this speaks well for its keenness of
eyesight. At times, these woodpeckers glean insects from the bark of
trees. In July, in the Yosemite Valley, hunting the twigs and bark for
insects seemed the favorite method of getting food.”
Dr. Joseph Grinnell (1908) saw one of these woodpeckers, in the San
Bernardino Mountains, drive a sapsucker away from its borings in an
alder and then go “the rounds of the borings” drinking from each. Dr.
Harold C. Bryant (1921) saw a California woodpecker robbing a nest of
a pair of western wood pewees; he was “calmly perched on the pewee’s
nest and eating one of the eggs. I could see the white and the yolk of
the egg on the woodpecker’s bill, as he raised his head. After watching
for some time, I attempted to frighten the robber away, but experienced
considerable difficulty in doing so. When he finally left the nest the
pewees continued to dart at him, to drive him farther away. Soon one of
the pewees, apparently the female, returned to the nest, picked up an
eggshell and flew off with it. I was unable to see what she did with
it. In half a minute she returned and began incubating the remaining
eggs.”
_Behavior._--The California woodpecker flies in true woodpecker
fashion, an undulating flight, interspersed with long dips during which
the wings are partly closed and somewhat pressed against the sides of
the body; during the rises the wings are flapped, displaying the black
and white markings conspicuously; there is an upward sweep before
alighting. Grinnell and Storer (1924) say: “When alighting on a tree
trunk, these birds assume a vertical posture, head out, tail appressed
to the bark. They move up by a hitching process--head in, tail out; up;
tail in, head out. If a bird perches on a small horizontal branch, his
position is more likely to be diagonal than directly crosswise. If a
bird alights on the square top of a fence post, he seems ill at ease
and soon backs over the edge into a more woodpecker-like posture.”
Mr. Dawson (1923) writes: “A most characteristic flight-movement is an
exaggerated fluttering wherein progress is at a minimum and exercise at
a maximum. In this way, also, they ascend at acute angles, sometimes
almost vertically. With this movement alternates much sailing with
outspread wings, and certain tragic pauses wherein the wings are quite
folded.” A similar flight is thus described by Grinnell, Dixon, and
Linsdale (1930) as follows: “Individual woodpeckers were often seen
making a kind of flight the object of which we did not determine. A
bird would fly in a nearly vertical direction from its perch for three
meters or more and then commence an irregular swooping flight, finally
coming back to the original perch.”
M. P. Skinner says in his notes: “In many of their ways, motions, and
mannerisms these birds strongly resemble the red-headed woodpeckers of
Eastern United States. Often they are very quiet and remain motionless
in one position for many minutes at a time. They are as apt to perch
crosswise as lengthwise of a horizontal, or nearly horizontal, limb.
At times, they hop along a limb, or the cross-arm of an electric pole,
while their bodies are turned a little sideways. Although one exhibited
the usual woodpecker habit of nervously jumping down backward, and
swaying from side to side, so as to be seen first on one side of his
dead stub and then on the other, he was really noticeably quiet and
motionless most of the time. One was seen in the Yosemite Valley on the
under side of a cottonwood twig, clinging there with his back down.”
Bendire (1895), on the other hand, says: “It is one of the most
restless Woodpeckers I know of, and never appears to be at a loss for
amusement or work of some kind, and no other bird belonging to this
family could possibly be more industrious.” This was my impression of
it, as well as the opinion of others.
Henry W. Henshaw (1921) evidently considered this woodpecker playful,
for he writes: “In searching for the motives underlying the storing
habit of the California Woodpecker we should not lose sight of the fact
that the several acts in the process, the boring of the holes, the
search for the acorns, the carrying them to the holes and the fitting
them in, bear no semblance to work in the ordinary sense of the term,
but is play. I have seen the birds storing acorns many times, and
always when thus engaged they fill the air with their joyous cries and
constantly play tag with each other as they fly back and forth. When
thus engaged they might not inaptly be likened to a group of children
at play.”
California woodpeckers are well known to be sociable birds and to live
more or less in communities or loose colonies, where food conditions
are favorable. But a most remarkable story of apparently communal
nesting is told by Frank A. Leach (1925). On February 2, 1922, he
discovered these woodpeckers excavating a nest in a wooden trolley
pole at Diablo, Calif. He estimated that they must have started work
on this hole about the middle of January and thinks that it was some
time near the latter part of April before it was finished. On March 1,
he “saw two go in one after the other. Both appeared to be working on
the inside. Two other birds on the pole showed interest in the work by
remaining there and taking an occasional peep into the hole.” On April
3, there were “from four to six woodpeckers about the place all day. On
one occasion saw three go into the hole. Heard digging while they were
inside.” On April 17, he saw “three birds go into the cavity and soon
after heard two of them working. Four other birds were on the pole, one
looking into the hole.”
The above extracts from his notes, made at frequent intervals and
often for several days in succession, would seem to indicate that
at least two, and possibly three, pairs of woodpeckers assisted
in the excavation of that nest, but evidently their work was not
very efficient, as the time involved was unusually long. The same
cooperative behavior continued during incubation of the eggs and the
feeding of the young, several different birds working in relays; and
this continued during the rearing of three broods of young that season.
He says that “in the case of the second brood, on eight different
occasions I saw three different old birds feed the young ones in the
nest, and at one time I witnessed a fourth one delivering food to
them.”
Referring to the third brood, he says:
In the large oak tree standing so near the trolley pole
that some of its outer branches nearly reached the
pole, there were almost always from six to eight mature
woodpeckers, all of which seemed to be interested in the
welfare of the nestlings in the pole. I repeatedly saw
three of them feed the youngsters, and on two occasions
noted four different old birds perform this parental
service. I was satisfied from the actions of the birds that
a majority of the flock, if not all of them, participated
in the care of the young woodpeckers. * * *
For others than the parent birds to feed the young was a
custom that was not confined to this group or flock at the
trolley pole. At about the time the young were leaving
that nest, I discovered another nest in a large oak tree
situated about a quarter of a mile distant from the pole,
where I found from one to five old birds, and possibly
more, very busy feeding the nestlings.
Major Bendire (1895) remarks: “The California woodpecker is by far
the most social representative of this family found within the United
States, and it is no unusual occurrence to see half a dozen or more in
a single tree. It is also a well-disposed bird, and seldom quarrels
or fights with its own kind or with smaller species; but it most
emphatically resents the thieving propensities of the different jays,
magpies, and squirrels, when caught trespassing on its winter stores,
attacking these intruders with such vigor and persistency that they are
compelled to vacate the premises in a hurry.”
According to some other observers, its behavior toward other species
is not always as friendly as it might be. M. P. Skinner writes to me:
“Once I found a California woodpecker and a California jay peaceably
perched in the top of a dead cottonwood. But at other times I have
noted much fighting between these woodpeckers and the jays, with the
woodpeckers apparently able to hold their own. On May 1, 1933, at old
Fort Tejon, I saw a California woodpecker make a vicious dive at a
plain titmouse that was clinging to the bark on the trunk of an oak.
On May 31 I saw one make a dive at an Arkansas kingbird on a fence
and drive it away. In May 1933 I found a pair of house finches that
had attempted to nest in a cavity high up in a dead stub of a black
oak. When I appeared, I found a California woodpecker throwing out the
straws and other nest material. The two finches were only a foot or
two distant, but they made no attempt to save their home, although it
is probable that they were scolding. Old acorn stores in the same stub
indicated that some woodpecker had an earlier claim to that stub than
the finches had.”
Howard W. Wright (1908) says:
January 18, while collecting at Newhall, California, I
wounded a Lewis woodpecker. The bird was able to fly
to another tree, and I noticed that some California
woodpeckers in a nearby tree became very much excited. As
the Lewis woodpecker lit on the tree trunk four California
woodpeckers attacked him evidently with the intent of
driving him off. The Lewis started for another tree but a
California flew at him from in front, and they both fell
in the struggle that ensued. At this the other California
woodpeckers, which were joined by a few more, set up a
violent chattering and when I ran up, to my amazement I
found that the Lewis had hold of the California by the
skull, two of its claws entering the latter’s eyes and the
other two entering the skull in front and behind. The Lewis
woodpecker was dead and the California so nearly so that it
died while I was removing the former’s claws.
_Voice._--Mr. Skinner says in his notes: “In May, at least, these
woodpeckers are sometimes noisy while calling to their mates. One gave
a ringing _cleep-ep_, _cleep-ep_ call on May 25, 1933. It was somewhat
similar to a flicker’s call.” Ralph Hoffmann (1927) says: “When a
bird lights on a pole or limb already occupied, there is always mild
excitement, fluttering of the wings, bowing and scraping, and always
a lively interchange of harsh calls, like the syllables _chák-a_,
_chák-a_, _chák-a chak_, dying off at the end.” W. L. Dawson (1923)
gives the following interpretations of its notes: “A jeering, raucous
voice, * * * _Jacob_, _Jacob_, _Jacob_; * * * _Kerack Kerack_;” and
“_chaar chaar tchurrup_.”
_Field marks._--The California woodpecker is conspicuously marked and
need not be mistaken for anything else from any angle. When flying
away, it looks like a black bird with an extensive white rump and with
a white patch in each wing; when flying over or when perched facing
the observer, the white abdomen and the broad black band across the
chest are distinctive; if near enough, the color pattern of the head is
easily seen.
[1] Prof. Ritter’s extensive book (1938) on the California
woodpecker appeared while this bulletin was in
press.--EDITOR.
BALANOSPHYRA FORMICIVORA ANGUSTIFRONS (Baird)
NARROW-FRONTED WOODPECKER
HABITS
The Cape region of southern Baja California is the home of this
subspecies. It is a well-marked race, which Ridgway (1914) describes as
“similar to _B. f. formicivora_, but wing averaging much shorter, bill
relatively larger, white frontal band decidedly narrower, lower throat
usually much more strongly yellow, white area on proximal portion of
remiges smaller, and the adult female with black area on crown much
narrower.”
William Brewster (1902) says of its haunts:
This woodpecker, which seems to be confined to the Cape
Region proper, is exceedingly abundant throughout the pine
forests on the higher mountains south of La Paz and common
in many places in the oaks at the bases of the mountains
and among their foot-hills, ranging downward, according to
Mr. Belding, to an elevation of about 700 feet. Mr. Frazar
found it most numerous on the Sierra de la Laguna, during
the last week of April and the first week of May. After
that its numbers decreased perceptibly. It began breeding
on this mountain the first week in June, but the breeding
season was not at its height until the middle of that
month. * * *
Only one specimen was seen at Triunfo during the last two
weeks of June, but the bird was common and presumably
breeding at Pierce’s Ranch in July. At the latter place
it fairly swarmed in December, the resident colony being
probably augmented by large numbers of winter visitors
from La Laguna, where Mr. Frazar found only a few birds
lingering in late November and early December. Along the
road between San José del Cabo and Miraflores it was seen
in considerable numbers on November 15, and three were
observed in some evergreen oaks at Santiago on November 23.
_Nesting._--There is a set of four eggs in the Thayer collection,
apparently the same set referred to by Mr. Brewster, collected by M.
Abbott Frazar in the Sierra de la Laguna, on June 3, 1887; the nest is
described as 10 feet up in a dead pine stump; the entrance measured 1¾
inches in diameter, and the cavity was 18 inches deep. The measurements
of these 4 eggs are =24.13= by 19.05, 22.61 by =19.56=, =22.61= by
19.30, and 23.88 by =18.80= millimeters.
The food and general habits of this woodpecker do not seem to differ
materially from those of the species elsewhere. It has similar
acorn-storing habits, for Mr. Frazar found “many dead pines literally
stuffed full of acorns.”
BALANOSPHYRA FORMICIVORA ACULEATA (Mearns)
MEARNS’S WOODPECKER
PLATE 28
HABITS
Along our southwestern border, from Arizona, New Mexico, and western
Texas southward over northwestern Mexico to Durango, we find this race
of ant-eating woodpecker. It was separated, named, and described by
Dr. Edgar A. Mearns (1890a) as follows: “General size and coloring
intermediate between _M. formicivorus_ and M. _formicivorus bairdi_;
throat less yellow than in either of them; bill shorter, more slender,
and less arcuate than in either of the other forms of M. formicivorus;
white striping of chest more than in the Pacific coast form, less than
in _formicivorus_.”
He says of its haunts (1890b): “A very common resident through the
pine belt, breeding plentifully. I have found it as high as the spruce
forests, but never in them. It is essentially a bird of the pines, only
occasionally descending to the cottonwoods of the low valleys. The oaks
which are scattered through the lower pine zone supply a large share of
its food.”
Henry W. Henshaw (1875) writes: “This woodpecker was first observed
when we neared Camp Apache, and, so far as my own observations go, its
range in Arizona is coincident with that of the oaks, the acorns of
which appear to constitute a very important item in its bill of fare.
We noticed it to the southward in every locality where oaks were found
in sufficiently large groves to afford it at once a place of shelter
and an inexhaustible source whence to draw food.”
Harry S. Swarth (1904), writing of the Huachuca Mountains, Ariz., says:
“A most abundant summer resident in the lower parts of the mountains;
a few winter here but they are scarce during the cold weather. I saw
but two or three during February and the early part of March, about the
middle of March they began to arrive in numbers, and by April 1 were
most abundant. Primarily a bird of the oak woods they seldom venture
into the higher parts of the mountains, breeding almost entirely below
6,000 feet.”
_Courtship._--We found this woodpecker quite common on the steep slopes
of the Huachuca Mountains in May 1922, especially in the vicinity
of Ramsay Canyon, between 5,000 and 6,000 feet elevation. They were
usually seen in the open groves of tall pines mixed with oaks. A
tall dead pine seemed to be one of their favorite resorts for their
courtship displays, which were both showy and noisy. They reminded me
of flickers as they dodged about the branches, chasing each other and
displaying their conspicuous markings.
_Nesting._--I have the records of four sets of eggs, all taken in the
Huachuca Mountains but in a variety of nesting sites. There are two
sets in the Thayer collection; one, containing six eggs, was taken on
May 10, 1897, from a hole 8 inches deep in the dead limb of a sycamore,
30 feet from the ground; the other set of five eggs was taken on June
1, 1902, from a cavity 10 inches deep in an ash stump, 20 feet from the
ground. A set of three eggs, in my collection, was collected by O. W.
Howard on May 31, 1901; the nest was 6 feet above ground in a dead oak
stump. Frank C. Willard took a set of five eggs on May 31, 1899, from a
cavity 15 inches deep, 35 feet up in a large dead pine stub.
_Eggs._--Mearns’s woodpecker evidently lays three to six eggs. Major
Bendire (1895) mentions a set of ten eggs, taken by F. H. Fowler,
which were “evidently the product of two females.” The eggs are pure
white, of course, and vary from short-ovate to rounded-ovate, with
only a slight gloss. The measurements of 20 eggs average 24.07 by
18.91 millimeters; the eggs showing the four extremes measure =26.8=
by =17.8= (a long narrow egg), 23.9 by =20.8=, and =22.4= by 19.5
millimeters.
_Plumages._--Mr. Swarth (1904) writes:
About July 1 the young birds begin to make their appearance
so like the adults in general appearance that it is
difficult to distinguish between them. The young of both
sexes usually have the entire crown red, as in the adult
male, but of a duller color, more of a brick red; but one
young female secured has the red area very limited and
coming to a point behind, so as to form a small, triangular
shaped patch on the crown. Of seventeen specimens collected
in the Huachucas, three show, more or less distinctly,
white markings on the outer tail feathers. In one of
these, an adult female, the marks consist of indistinct
white spots, mostly on the inner web. The other two,
juvenile females, have the outer feathers distinctly,
though irregularly, barred with white for about half their
length.
_Food._--The food of this woodpecker is evidently similar to that of
other races of the species. Dr. Mearns (1890b) remarks: “Its habit of
industriously hoarding food in the bark of pines, and in all sorts
of chinks and hollows, is well known. These stores are the source of
unending quarrels between this woodpecker and its numerous pilfering
enemies; and I have laid its supplies under contribution myself, when
short of provisions and lost from the command with which I had been
traveling, by filling my saddlebags with half-dried acorns from under
the loose bark of a dead pine.”
_Behavior._--Mrs. Bailey (1928) says: “An odd habit of the woodpeckers
was happened on by Mr. Ligon in the Black Range. At dark, on March
15, 1913, seeing a bird enter a hole about eight feet up in an oak he
closed it after it, and in the morning when he returned was surprised
to find six birds in the one hole. As the woodpeckers do not nest until
the last of May, and then in high dead pines, it was, of course, a
night roost.”
Ed. S. Steele (1926) tells the following story: