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Downy
Woodpecker
Picoides pubescens [Northern
Downy Woodpecker]
Contributed by Winsor Marrett Tyler
[Published in 1939:
Smithsonian Institution United States National Museum Bulletin
174: 52-68]
The downy woodpecker *** inhabits nearly the whole of the
wooded parts of North America. It is absent or rare on the arid
deserts and less common in the densely forested regions than some
of the larger woodpeckers; its favorite country is the open
woodland that covers a large part of the United States.
When civilized man invaded their territory, the downy
woodpecker *** did not retreat before his advance but accepted as
a home the orchards and shade trees with which man replaced the
forest. At the present time it builds its nest sometimes within
sight from our windows and often in the parks of our large cities.
It is one of the best known of our permanent residents.
The ornithologists of a century ago show unanimity in their
characterization of the bird. Audubon (1842) remarks that it
"is perhaps not surpassed by any of its tribe in hardiness,
industry, or vivacity"; Wilson (1832) says that "the
principal characteristics of this little bird are diligence,
familiarity, perseverance" and speaks of a pair of the birds
working at their nest "with the most indefatigable
diligence"; and Nuttall (1832) characteristically shares
Wilson's opinion even to the extent of employing his exact words,
"indefatigable diligence," in his own account of the
building of the nest. Nearly a hundred years later Forbush (1927),
when near the end of his long life, put his seal of approval upon
this sentiment, expressed long ago, by summarizing the downy as a
"model of patient industry and perseverance."
Backed by these authorities we may regard the downy woodpecker
as a bird with a stable and well-balanced nature, a bird which,
unconcerned by the rush and traffic "of these most brisk and
giddy-paced times," still perseveres in its
"indefatigable diligence."
Spring and Courtship.--As
spring advances, the downy woodpecker seems to wake up; it
attracts our notice by its more frequent notes and increased
activity. During the cold months of the year the bird has been
comparatively silent, although even in the depth of winter we may
occasionally hear its single chip and even the long whinny,
but in April, for so sedate a bird, it becomes a lively
personality; it moves about quickly--sometimes with lightninglike
agility--and takes a voluble interest in the members of its own
species.
Frances H. Allen, in his notes, gives the two following graphic
accounts of the initial stage of the bird's courtship: "April
10, 1904. West Roxbury, Mass. I found two downy woodpeckers
courting--at least, I suppose that was what they were up to. They
acted like mating flickers, chasing each other about from tree to
tree, keeping almost constantly on the move and only pausing now
and then to execute a sort of dance, spreading their wings and
tails. From time to time I heard from them a long call resembling
the flicker's whick, whick whick whick, etc., but higher
pitched than the flicker's and, of course, not so loud. Less often
I heard another note--a softer, slighter, more hurried call,
similar in quality. I did not make out whether these two calls
were made by different sexes, nor did I positively make out that
the birds were a pair, they kept in such constant motion. At least
once one lit crosswise of a twig. At last one flew off, and then
the familiar and characteristic long call of a downy sounded from
another direction, and the remaining bird flew over to the third
bird, which was clinging to the trunk of an elm. Then these two
stayed in each other's company but did not conduct so elaborate a
dance as the first couple.
"All this time a fourth bird had been drumming on a tree
not far away. I went up to the place and timed the drum calls,
finding each roll to last about two seconds. I could not count the
taps, but thought they numbered eight or ten to each roll. While I
watched this bird, another downy came along, sounding the
flickerlike call, but rather faintly, and the drummer flew to join
her. They flew off together. I believe it is only the male that
drums, and I think it probable that the bird that answered the
drummer was the one that had taken part in the dance before
described, for that bird when she left her partner had flown off
in this direction.
"April 8, 1917. West Roxbury. Watched a pair courting this
morning for several minutes. Both sexes had a curious 'weaving'
action, moving the head and whole body from side to side on the
tip of the tail as a pivot with the neck stretched out and bill
pointed on a line with the body, and the whole body elongated.
They did this both when clinging to the side of a trunk and when
on a horizontal or slanting branch. They were silent but very
active, flitting one after the other from branch to branch and
tree to tree, but making only short flights. The waving, or
'weaving,' motion of the head was rather rapid, perhaps two waves,
that is from left to right and back again, in about a second--but
this is stated from general impressions and memory only. These
birds did not spread the wings and tail as did the courting pair
observed on April 10, 1904, and, as stated, they uttered no
note."
My notes refer to a bit of courtship observed during the actual
breeding season, May 11, 1911, in a wooded swamp in Lexington,
Mass., where the species used to nest every year. The female bird
was perched motionless along a horizontal limb of a tree, and the
male was poised in the air just behind and a little above her. He
was hovering. His wings were more than half spread, I should say,
and waving slowly up and down, a maneuver which displayed finely
the rows of white spots on the flight feathers and coverts.
William Brewster (1936), in his Concord journal under date of
May 5, 1905, notes another form of courtship. He says: "At 8
a.m. saw a pair of Downy Woodpeckers in young oaks behind Ball's
Hill, behaving very strangely. They kept flying from tree to tree,
flapping their wings slowly and feebly like butterflies, sometimes
moving on a level plane, sometimes in long loops, occasionally
sailing from tree to tree in a long deep loop. Their wings
had a strange fin-like appearance due, probably, to the way they
were held or flexed. They both uttered a low, harsh, chattering
cry, almost incessantly. No doubt this was a love performance, but
they were male and female and both 'showed off' in the same
way."
Lewis O. Shelley (1932), who, at East Westmoreland, N.H., has
had an extensive experience with banded birds throughout the year,
describes the courtship thus:
Courtship activities begin rather early with the male's
tattooing commencing in the warm days of March. I believe the most
active mating display is given by a new male that desires a mate,
not by a male mated the previous year whose mate is still living.
The latter male seems to give a protective display to its rival,
seemingly just enough to hold his mate's trust.
In the spring of 1931, father and son. . .fought for and
sought the favor of the young female. . .the son finally winning
after days of courtship in our yard and vicinity. . . . Courting
lasted for upwards of two weeks, or perhaps longer, before the
female made her choice. Of the two rivals the son finally was
accepted, the older male shortly disappearing. . . . The courtship
display of these three birds was the same as I have observed with
other mating Downy Woodpeckers elsewhere in past seasons. At my
station the mating activities began when the birds first met and
was continued more or less regularly thereafter. The female is
usually rather quiet, sometimes giving a 'week, week, week, week,'
or again a squeaking note. The male gives forth a loud 'wick,
wick, wick, wick, wick, wick,' sometimes with a rolling
'k-k-k-k-k' at the end. Very little drumming on resonant objects
is done by the male, once the female is located, and in this case
almost none was done except when one male was out of sight and
hearing of the female and the other courting bird. To the casual
observer, the chasing of the female by the male to a tree, and
from tree to tree, in a seemingly idle manner (often, but not
always, by both males) is in reality a part of the mating
maneuvers.
When it happens that both males are in pursuit, the
activities take on an added impetus. I have a number of times seen
one male dash headlong across a fifty-yard opening to where the
other two birds were, loudly uttering his cry, and, when
alighting, dash at his adversary, the female squeaking
intermittently, and swinging her body from side to side. The
display also consists of spread wings nervously fluttered; raising
and lowering of the scarlet patch, mad dashes from one tree to
another at the fleeing female, who dodges to the opposite side of
the tree as the pursuing bird alights; loud calls at intervals
when he stops his mad hopping up the limbs and smaller branches.
This activity may last from five to thirty minutes, from the large
elm in our yard, where the birds feed, to a larger area either
south or east of the house. When two birds are alone together, it
is common to find them perching near together and motionless for
considerable periods of time, but let the second male appear and
the first male will drive the female from the tree and the round
is begun again. When two males come face to face in a headlong
rush, wings spread, crest raised, and beak open in a challenging
attitude, it is mostly sham, for they soon quiet down unless one
advances up the tree toward the female clinging immovable above.
There is a period when the male is very active in his
rushing of the female--I suppose to make sure of his desire, a
mate--but this phase of courtship plays no part in the act of
copulation, which I have seen enacted early in the morning, a
quiet, matter-of-fact performance.
The first and last paragraphs of this quotation are taken from
Mr. Shelley's manuscript notes.
Nesting.--The downy woodpecker
nests in a cavity that the birds themselves drill in a branch or
stub 8 feet (rarely less) to 50 feet (rarely more) above the
ground, generally in dead or dying wood, sometimes in a solid
branch. The entrance, one and a quarter inches in diameter, is
just large enough to admit the bird's body, and is perfectly
circular unless some bits of soft wood chip off. The cavity is
roughly gourd-shaped, turning downward and widening soon after
penetrating the wood, and extends to a depth varying normally from
eight to twelve inches. Generally a few chips are left in the
bottom of the cavity.
Lewis O. Shelley says that according to his experience
"the female selects the nest site on her winter, or
year-round, territory." He speaks of a female that in the
fall "partly dug out a cavity, supposedly for her winter
quarters, but the following summer I found a brood of young of
this same bird occupying the nest."
Writers are almost unanimously of the opinion that both birds
of the pair excavate the nest, but Shelley states: "Of a
number of nests observed, I have never known the male downy to
assist in excavating. He often comes near when the female is
working, but this seems to be an understood signal for her to
cease work and go off in his company."
A. Dawes DuBois, in a letter to Mr. Bent, describes the
behavior of a pair working jointly on a nest in Ithaca, N.Y.,
about 15 feet up in an old stub. He says: "These birds were
working the lower depths. The partners worked alternately. First
the female lighted on the stub and disappeared within the cavity.
Immediately she thrust out her head, and, with a quick shake,
disposed of a billful of chips. She repeated this a number of
times. She was throwing out the loose chips from the bottom of the
cavity. Soon she began to chisel, remaining inside where we could
not see her. After she had been working for five or six minutes,
her mate flew to the stub and uttered a chirp, whereupon the
female came out and flew away.
"The male went in to continue the work by a somewhat
different method. He was never entirely lost to view--his tail was
always visible--and he backed out of the hole to dispose of the
chips. He ruffled his feathers considerably in squirming out
backward, as his body was a snug fit in the entrance hole. He
threw out a quantity of loose chips in this manner and then began
chiseling, his tail meanwhile protruding from the doorway. He
worked for 22 minutes; then his mate came back.
"She went inside and came out with her mouth quite full of
chips; but instead of tossing the chips on the ground, she flew
off with them to another tree. She stayed away for several
minutes, then returned and went to work in her accustomed way,
staying within the cavity, and thrusting only her head outside.
When she had worked about 15 minutes the male came again to the
entrance. She put her head out of the doorway; they rubbed their
bills together and chirped a few remarks. The female then flew
away and the male took up the task again."
Audubon (1842) says: "About the middle of April it begins
to form its nest, shewing little care as to the kind of tree it
selects for the purpose, although it generally chooses a sound
one, sometimes, however, taking one that is partially decayed. The
pair work together for several days before the hole is completed,
sometimes perhaps a whole week, as they dig it to a depth of a
foot or sixteen inches. the direction is sometimes perpendicularly
downwards from the commencement, sometimes transverse to the tree
for four or five inches, and then longitudinal. The hole is
rendered smooth and conveniently large throughout, the entrance
being perfectly round, and just large enough to admit one bird at
a time."
A. Dawes DuBois writes that the male bird of a pair was caught
in a nest 6 feet from the ground, evidently incubating the six
eggs well advanced in development. This observation is in accord
with the general belief that the male takes his share in
incubation.
Mrs. Alice Hall Walter (1912) states that: "in the North,
only one brood is raised during a season; but it is not uncommon
in the South for one brood to be raised in May and a second in
August."
Eggs.--[AUTHOR'S NOTE: The northern
downy woodpecker lays ordinarily four or five eggs, though sets of
three or six are not rare, and as many as seven or even eight eggs
have been found in a nest. The eggs are pure white, either dull
white or more or less glossy, and they vary in shape from ovate to
rounded-ovate. The measurements of 55 eggs average 19.35 by 15.05
millimeters; the eggs showing the four extremes measure 22.35
by 16.26, 17.78 by 14.73, and 18.80 by 13.97
millimeters.]
Young.--The incubation
period of the downy woodpecker is 12 days, according to Frank L.
Burns (1915) and Dr. Arthur A. Allen (1928).
Whether in their earliest days the young birds, hidden in the
depths of their dark chamber, are fed by regurgitation has not
been determined, but very soon after they leave the egg food is
brought directly to them. Dr. Allen says: "Certainly by the
time the young are four or five days old entire insects are bought
in the parents' bills and given to the young; I have photographic
proof of this."
Craig S. Thoms (1927), in a study of the nesting habits in
South Dakota, says: "On June 9 the young were beginning to
come up to the door of their excavation to receive food.
Presumably the largest and strongest sticks his head clear out.
When he fed he subsided and the next came up, but not quite so
far. He in his turn subsided and the parent entered to feed the
weaker ones still farther down. . . .
"On June 12 the last of the young left the nest, which
upon being measured was found to be 10 inches deep."
A. Dawes DuBois tells of the flight of the young birds from the
nest: "The young chattered most of the time during the last
two days of nest life. One at a time they looked out a great deal
at the strange outer world. They left the nest on June 11. The
last two, a male and a female, left during the afternoon, each
after being fed at the entrance and seeing the parent fly away.
The young male flew from the nest hole straight to a tree 60 feet
away. His sister quickly followed, lighting on the trunk of the
same tree and following her parent up the bole in the hitching
manner of their kind as though she had been practicing this
vertical locomotion all her life."
Plumages.--[AUTHOR'S NOTE: Young
downy woodpeckers are hatched naked and blind, but the juvenal
plumage is acquired before theyoung leave the nest. In this first
plumage, the young male is much like the adult male, except that
the red nuchal patch is lacking; the forehead is black, spotted
with white, but the crown and occiput are more or less marked with
various shades of red, pinkish, or yellowish, as well as spotted
with white; the black portions of the plumage are duller than in
the adult; the sides of the breast are streaked and the flanks
obscurely spotted with dusky; the white areas, underparts, and
white spots elsewhere, as well as the rectrices, are tinged with
yellowish.
The young female is like the young male, except that there is
no red on the head, and the crown is clear black, or black spotted
with white. L. L. Snyder (1923) has shown that young males
sometimes have only white markings on a black crown and that young
females sometimes have reddish, pinkish, or yellowish markings on
the crown.
The juvenal plumage is worn but a short time, for a complete
molt, beginning in September or earlier, produces a first winter
plumage which is practically adult. Adults have a complete annual
molt from July to September. Both adults and young show a tinge of
yellowish in the white areas in fresh fall plumage, which
gradually fades away.]
Food.--F. E. L. Beal (1911) in an
examination of the contents of 723 stomachs of the downy
woodpecker found that 76.05 percent was animal matter, the
remaining 23.95 percent vegetable matter. The following quotations
are from his exhaustive report.
Beetles taken collectively amount to 21.55 percent, and are
the largest item of the food. Of these, a little less than 14
percent are wood-boring larvae. . . . They were found in 289
stomachs, or about 40 percent of all, and 10 contained no other
food. This is only about half the amount found in the stomachs of
the hairy woodpecker, and shows that the downy pecks wood much
less than the hairy. These larvae are eaten at all times of the
year, though the most are taken in the cooler months. . . . The
economic value of the destruction of these larvae is very great.
Weevils amount to a little more than 3 percent but appear to
be a rather favorite food, as they were found in 107 stomachs. . .
.
Ants are eaten by the downy to the extent of 21.36 percent
of its diet, and are taken more regularly than any other element
of the food. . . .
Caterpillars appear to be a very acceptable food for the
downy woodpecker, as they constitute 16.50 percent of the yearly
diet. . . .
Fruit was eaten to the extent of 5.85 percent of the whole
food. Most of it is useless wild varieties. . . .
The charge sometimes made that the downy injures trees by
eating the inner bark is disproved. It eats cambium rarely and in
small quantities.
Beal gives a list of 20 seeds and fruits found in the downy's
food. Summarizing his findings, he says: "The foregoing
discussion of the food of the downy woodpecker shows it to be one
of our most useful species. The only complaint against the bird is
on the score of disseminating the poisonous species of Rhus.
However, it is fortunate that the bird can live on this food when
it is difficult to procure anything else. The insect food selected
by the downy is almost all of species economically harmful."
Forbush (1927) lays stress on the usefulness of the downy to
man; he says that it "searches out the pine weevil which
kills the topmost shoot of the young white pine and so causes a
crook in the trunk of the tree, unfitting it for the lumber
market."
Mrs. Alice Hall Walter (1912) shows how well the downy is
equipped to secure its food. She says that the feet, two toes in
front and two behind, "serve to clamp the bird to the
tree." She continues:
Additional support is furnished by the stiff, sharply
pointed tail-feathers, that act as a brace when the bird delivers
heavy blows with its beak. Effective as this tool is for the work
of hammer, wedge, drill and pick-axe, it could not obtain the
deeply hidden grubs known as "borers," from their
tortuous, tunneled grooves, without the aid of the long, slender,
extensile tongue. In the case of the Hairy and Downy, as well as
some others of the family, this remarkable tool is provided with
barbs, converting it into a spear, which may be hurled one inch,
two inches, or even more, beyond the tip of the beak.
A. Dawes DuBois says in his notes: "I have seen a downy
woodpecker industriously applying the percussion test to the dried
stalks of the previous summer's horse weeds, which grow to
prodigious size in the creek bottoms near Springfield, Illinois.
He went up each stalk, tapping it lightly, and frequently stopping
to pierce the shell and extract a worm from the pith. I found that
the weed stems he had visited were punctured and splintered in
numerous places."
The following note by Elliott R. Tibbets (1911) shows how agile
the downy is on the wing. He was watching some birds at a feeding
shelf. "I was told," he says, "to throw a cracked
nut into the air and see what followed--I did so, and, to my
surprise, the Downy darted after it, not allowing it to touch the
ground, and then returned to the evergreen, where he proceeded to
pick the kernel from the hard shell."
Henry D. Minot (1877) also mentions that they "catch
insects on the wing."
Behavior.--The downy woodpecker
sits very still as it digs out a grub from under the bark of a
tree, or from the wood under the bark, or as it dislodges a bit of
bark in its hunt for a cocoon or a bundle of insects' eggs. We
hear the gentle taps of its bill, and when our eyes, led by the
sound, catch sight of the bird, perched on a branch or the trunk
of a tree, we understand why it has been called industrious. It is
concentrated on its work; it works patiently, seriously, like a
carpenter working earnestly with his chisel, spending a full
minute, sometimes more, to secure a bit of food.
As it sits there quietly, working painstakingly at the bark, it
gives the impression of a rather sedentary bird, deliberate and
staid, but when it begins to move about--taking short flights
among the branches--alighting on little swaying twigs and flitting
off again--we see it in another mood. It is lively now; all
deliberateness is gone. It hops upward over the branches with
quick jerky hops, rearing back a little after each one; it may
descend a little way by backward hitches; it winds about the
smaller branches peering at the right side, the left side, and
around at the back; it flits to a twig no thicker than a pencil
for the space of a single peck, and then it is off with the speed
of an arrow, weaving and undulating through a maze of branchlets,
cutting the air audibly with its wings.
We can watch the downy woodpecker best in winter when the trees
and shrubs are bare. But even in such an exposed situation as a
leafless tree, we do not find it a conspicuous bird--one hop and
it is hidden behind a branch, seeming almost to glide out of our
sight. At the slightest alarm it disappears; it uses a branch as a
shield--slipping behind it, safe from observation or attack.
The bird is at home also in shrubbery, moving easily among the
smaller branches, hitching along their slender length, picking at
the bark, and leaping from one branch to another with the aid of a
flip of the wings. It sits crosswise on a perch scarcely bigger
than a twig, leaning forward a little, bill outstretched,
suggesting in position and outline a tiny kingfisher.
Here, at close range, on a level with our eyes, we realize how
rapid the bird's motions are. The beak strikes and draws back--the
two movements in a single flash. The head turns to one side, to
the other side, bringing first one dark shining eye, then the
other, to bear on the bark; we see the head in the two positions,
although we get only a hint of the motion between.
Thus the day's work goes on, until the downy, replete with the
results of its industry, rests motionless for a while on a high,
sunny branch, taking its ease.
The downy woodpecker, like most of its family, has an
undulating flight when flying any considerable distance. The
undulations are not deep, as in the plunging flight of a
goldfinch; it gives rather the effect of a ship pitching slightly
in a head sea. A few strokes carry the bird up to the crest of the
wave--the wings clapping close to the sides of the body--then, at
the crest, with wings shut, the bird tilts slightly forward, and
slides down into the next trough.
Besides employing its strong beak and the powerful muscles of
its neck to secure food and dig out a cavity for its nest, the
downy woodpecker makes use of them to beat a loud tattoo on the
branch of a tree or some other resonant object. This habit is
oftenest noticed in spring, when it appears to form a part of
courtship or a prelude to it, but Lewis O. Shelley says in his
notes that "on February 3, 1934, a male downy commenced its
drumming on a dead elm branch near the house. A few hours earlier
the temperature had been 5o
below zero. On the 6th, 8th, and 9th he was tattooing at the usual
hour, about 8 a.m. On the 8th the temperature registered zero, and
on the 9th 18o below zero!"
Dr. Charles W. Townsend, in his Ipswich manuscript notes, under
date of March 16, 1930, speaks of "a male bird hammering a rat-at-at-too
on the apex of a telephone pole for three seconds. He then paused,
hunching up a little and looking about for from five to twelve
seconds, before resuming the hammering. He made a small round dent
in the pole, but there were no chips."
A. Dawes DuBois tells in his notes the following anecdote:
"One April day I watched this avian drummer as he entertained
himself by beating on the wooden insulator-pins of an unused
cross-arm on a telegraph pole. From each pin he rang out a
different tone--loud, clear, and high-pitched. It was evident that
this pleased him, for he hopped from one pin to another to repeat
the variations."
I have found in the books no mention of drumming by the female
downy, but at the end of the extract from William Brewster's
notes, quoted under "Courtship," in which he describes a
mutual display by a pair of birds, he adds: "Both sexes drum,
also."
William Brewster (1876b) points out the difference between the
tattoo of the downy woodpecker and that of the hairy woodpecker
and the yellow-bellied sapsucker. He says: "P. pubescens
has a long unbroken roll, P. villosus a shorter and louder
one with a greater interval between each stroke, while S.
varius commencing with a short roll ends very emphatically
with five or six distinct disconnected taps."
R. Owen Merriam (1920) gives, from Hamilton, Canada, an
instance of "snow bathing." He says:
This morning a female Downy Woodpecker that I was watching
flew to a horizontal branch and proceeded vigorously to bathe in
the loose snow lying there. Like a Robin in a puddle, Mrs. Downy
ducked her head, ruffled her feathers, and fluttered her wings,
throwing some of the snow over her back and scattering the rest to
the winds. As all the snow fell off one part of the branch, she
moved along to another, until she had cleared a place about two
feet long. Two forks held more snow than the straight limb, and
apparently Mrs. Downy enjoyed herself immensely when she came to
them.
Dr. Arthur A. Allen (1928) in his admirable "Downy
Woodpecker's Story," published in the School Department of Bird-Lore,
says, letting the bird tell its own story: "When cold weather
sets in, . . .I begin drilling roosting-holes where I can spend
the nights. I usually have to drill quite a number for they seem
to be quite popular with other birds like the Chickadees and
Nuthatches, and sometimes when I get ready to retire I find my
hole occupied by a flying squirrel or a whole family of deer mice,
and it is easier to drill a new hole than to drive them out. One
winter I got tired of drilling holes and every night retired to a
bird-house and perched on an old Wren's nest that was in it."
Many ornithologists, even as long ago as the time of Wilson and
Nuttall, have believed that the rows of small holes, such as we
commonly see in the bark of our orchard trees, are drilled by the
downy woodpecker. These little holes, about three-eighths of an
inch across, circular when old, but oval when fresh, are arranged
in fairly regular rows parallel to the ground, and sometimes in
tiers, when they have the appearance of a waffle. In settled
regions they are found oftenest in the trunks of the larger
branches of trees belonging to the rose family--most commonly of
all in apple trees. The holes may be within 3 feet of the ground
or as high as 20 feet or more above it, depending on the height of
the tree. Oftentimes they are very close together; I have counted
as many as six of them in a space of an inch and a half. The
question has arisen whether the downy woodpecker ever makes these
holes.
We know now, what the older ornithologists did not know, that
it is a regular habit of the yellow-bellied sapsucker to drill
such holes, but there are plenty of statements in the
ornithological literature today ascribing the work to the downy
woodpecker as well.
Dr. Charles W. Townsend (1932) gives an able summary of the
literature on this question and, after carefully weighing the
evidence, comes "to the conclusion that these well known and
characteristic circles of holes are made by true sapsuckers and
not by downy or hairy woodpeckers."
He throws a good deal of doubt on some seemingly definite
observations from correspondents quoted by Forbush in his
"Birds of Massachusetts," when he says that "many
leave one in considerable uncertainty as to whether the
correspondents actually saw the downy woodpecker making the rings
of holes, or merely tapping in the same region, or drinking the
sap, or eating cambrium from holes whose origin was not
ascertained. It may be that some of the correspondents were unable
to distinguish the true species of woodpecker."
Dr. Townsend cites several observations, two of which are
quoted below. If the first of these had not been correctly
interpreted, and if the other had not been seen in its entirety,
they might have led to error. He says:
There is one observation, however, which should be quoted
here, as it is of considerable interest in this discussion, an
observation made by a capable observer with great care. Forbush
says *** : "The first trustworthy evidence, however, that I
obtained regarding the tapping of trees for sap by the Downy
Woodpecker was in 1899, when my assistant, the late Charles E.
Bailey, on April 6 watched one for several hours. His report
reads: 'At 12:30 I found a Downy Woodpecker, and watched him till
2:45; he took three larvae from a maple stub, just under the bark.
He next tapped two small swamp maples, four and six feet from the
ground, and spent most of the time taking sap. He tapped the tree
by picking it a few times very lightly; it looked like a slight
cut, slanting a little. The bird would sit and peck the sap out of
the lower part of the cut. The cut was so small the sap did not
collect very fast. The bird would go and sit for a long time in a
large tree and not move, then it would come back and take more
sap. It did this three times while I was watching it. It did not
care to take any food but sap.'. . . Mr. Bailey cut off and
brought me the limb, the bark of which was perforated by the bird.
. . . The perforations passed through the bark to the wood, but
did not enter it and they do not in the least resemble in shape
those made by the Yellow-bellied Sapsucker." Here is just
what we should expect in a woodpecker not specialized as a
sapsucker. . . .
The next record is of considerable significance in this
discussion, and had I seen only the latter half of the drama, my
conclusions might have been different. In the Wenham swamp on May
11, 1906, my notes state that Glover M. Allen and I found a
Yellow-bellied Sapsucker drilling holes in a white pine. His
movements were slow and he paid little attention to us standing
below him at the foot of the tree. When he departed, a female
Downy Woodpecker visited the holes.
Speaking of his own observations, Dr. Townsend says: "I
may state that, although I have long watched Downy Woodpeckers
gleaning insects on and in the bark and wood of trees at all
seasons of the year, I have never seen them dig circles of holes
in the bark. . . . I have never found fresh rings of holes except
during the time of the sapsucker migrations."
Voice.--The downy woodpecker is by
no means a noisy bird; compared to the red-headed woodpecker, with
its loud rattling calls, or to the shouting, boisterous flicker,
it is quiet and demure. Nevertheless, we cannot be for long near
one of these little birds, hidden high among leafy branches,
before we learn of its presence. Within a few minutes, long before
we catch sight of it, we are almost certain to hear its voice.
Its call note is a single abrupt syllable, like tchick.
Although this note is of sufficient volume to carry a considerable
distance, it is not a loud note even when heard at short range. As
in the case of many bird notes, it is recognizable from the voice
of any other bird hereabouts once we have become familiar with it,
yet it is not easy to say how it differs from numerous other calls
that might be suggested by the same letters. I believe one
characteristic of the note that helps us distinguish it is its
shortness--it is over almost as soon as begun, like a dot in the
telegraph code. But in spite of being sharp, it is a modest little
sound; it does not ring through the woods like the wild call of
the hairy woodpecker.
Another note is a long whinny made up of a dozen or more tchicks.
These increase in rapidity soon after the beginning of the series,
and the pitch drops rather sharply. Near the close, the volume
diminishes, and the whinny ends with a "dying fall."
Elizabeth Sampson (1934) brings this note very clearly to our
mind when she speaks of it as "a handful of his staccato
notes. . .flung out in a rapid run, gaining speed as they came,
till they almost tumbled over each other at the end."
This whinny is also given, although not often, without any fall
in pitch.
The downy woodpecker has other notes in its vocabulary, some of
which are described under courtship, but, compared to the two
noted above, they are rarely heard. It may be that some of these
notes are only modifications of the call notes, uttered with a
slightly changed inflection. One, a single short note, has a
distinct vocal quality.
Of the young birds in the nest, Dr. Arthur A. Allen (1928) says
that they "keep up an incessant chippering, especially when
they get the least bit hungry, and at times they sound almost like
a beehive, from the ground."
After the young birds have left the nest, I have often heard
them give a series of tchicks similar to the whinny of the
adults, but in a weaker voice and all on the same pitch.
However, this note evidently varies, for Francis H. Allen says in
his notes that the young have also a rattle resembling the
kingfisher rattle of D. villosus, but fainter and falling
in pitch like the similar note of the adult.
Field marks.--The downy, the
smallest of our woodpeckers, maybe separated at once from any
other woodpecker, except the hairy, by the broad white stripe down
the back.
The hairy is half again as large as the downy, but in
situations where comparative size counts little, the downy may be
recognized by its short bill--no longer than its head. The hairy's
bill is longer even in proportion to the size of the bird.
Enemies.--Lewis O. Shelley, who as
a bird bander has handled many downy woodpeckers, says in his
notes: "I find this species practically free from parasites,
but I have found among the feathers the two bird flies, Ornithoica
confluenta and Ornithomyia anchineuria."
Alexander Wilson (1832) shows that the house wren, although not
an open enemy of the downy, causes it a good deal of annoyance by
stealing its nest sometimes. He says:
The house wren, who also builds in the hollow of a tree, but
who is neither furnished with the necessary tools nor strength for
excavating such an apartment for himself, allows the woodpeckers
to go on, till he thinks it will answer his purposes, then attacks
them with violence, and generally succeeds in driving them off. I
saw some weeks ago a striking example of this, where the
woodpeckers we are now describing, after commencing in a cherry
tree within a few yards of the house, and having made considerable
progress were turned out by the wren; the former began again on a
pear tree in the garden, fifteen or twenty yards off, whence,
after digging out a most complete apartment, and one egg being
laid, they were only once more assaulted by the same impertinent
intruder, and finally forced to abandon the place.
Maurice Thompson (1885) describes thus the bird's defense
against the attack of a goshawk:
I once saw a goshawk pursuing a downy woodpecker, when the
latter darted through a tuft of foliage and flattened itself close
upon the body of a thick oak bough, where it remained as
motionless as the bark itself. The hawk alighted on the same bough
within two feet of its intended victim, and remained sitting there
for some minutes, evidently looking in vain for it, with nothing
but thin air between monster and morsel. The woodpecker was
stretched longitudinally on the bough, its tail and beak close to
the bark, its black and white speckled feathers looking like a
continuation of the wrinkles and lichen.
More commonly, when attacked by a hawk, the downy dodges behind
a branch and, if the hawk catches sight of it again, either winds
round the branch or dives behind another one. By this adroit
defense the downy has a fair chance of eluding the hawk's attack.
Fall and Winter.--We
see little change in the behavior of the downy woodpecker at the
approach of autumn, at the time when many of the migratory birds
are beginning to show a daily increasing restlessness, seeming on
tiptoe to start on their long journey, moving about actively in
their new feathers, and breaking out sometimes with a phrase of
postnuptial song. In the role of permanent resident, the downy
remains calm in the midst of the bustle of travel; it may join the
hurrying groups for a time, or become surrounded by them, but it
does not catch the contagion of departure, and soon drops
behind to continue its local round.
The downy is not forced to seek the sun and warmth and the
inexhaustible food of the Tropics, for the woodlands of New
England and southeastern Canada are stored with food that, with a
roosting hole, enables the bird to withstand the severest winter.
But this food is limited; the insects that have been multiplying
all summer, thus adding continually to the woodpeckers' supply of
food, stop multiplying when the frosts come, and will add no more
until spring.
The downy is not a bird that ranges widely in search of food;
moreover, for protection against the weather it is held to the
vicinity of its roosting hole. Therefore each bird, in order to be
sure of sufficient food for itself during the cold months, must
maintain dominion over a territory large enough to support it
through the winter.
Thus it comes about that in autumn the downy does
perforce change its habits, or rather its attitude toward other
birds of its species. The families disperse, and until the next
breeding season each individual becomes a solitary bird, living in
a restricted region, which it defends against trespass, resenting
and repelling the approach of any other downy woodpecker.
This reversal of attitude or character--the change from a
member of a family to an anchorite in fall, and back again in
spring--takes place gradually, we may suppose, and not exactly at
the same time in every bird. Hence one bird meeting another in
autumn, while the change is in progress, may underestimate the
degree to which it has drawn away from its fellows, or, in the
spring, may overestimate the amount of cordiality that has
returned to the wintering anchorite. This lack of understanding
may give rise to behavior difficult or impossible for us to
interpret.
Sometimes the relationship between two downies is clear enough,
as when, on September 20, 1910, I saw a male fly repeatedly at a
female in a menacing way and drive her off; and when on November
3, 1935, I saw a female bird fly toward a male, which was perched
near a hole in an electric light pole, from which he did not
retire, as a perched bird commonly does when approached by a bird
on the wing, but held his ground while she flew away; and when
Lewis O. Shelley tells of a female bird "rushing with
antagonistic attitude at her two daughters" and also driving
off her granddaughters whenever they invaded her winter territory
in autumn, all these birds being identified by bands.
There are cases, however, in which the relationship between the
birds is very puzzling. In the following scene, from my notes,
there is a hint of hostility or remonstrance, but a suggestion of
courtship also--out of place, it seems in autumn between two
female birds. "October 15, 1935. Two birds are in a large,
bare maple tree; one is noticeably larger than the other, but
neither one has a red occipital patch. They keep near each other,
one following the other by short, quick flights. They perch
perfectly motionless for a moment a foot or two apart; then both
together sway their heads, swinging them quickly down and up to
one side, down and up to the other side. The swing is very rapid,
like the wink of an eye. They flit their wings upward and outward,
also with the speed of a wink, over and over--all this without a
sound. They fly behind a branch sometimes but keep mostly in the
sight of each other, and, although neither attacks, each seems
wary of attack and dodges away when approached. They sometimes
alight on very slender branches, and once a bird goes to the
ground where it stands with its head held high up. They move very
actively and lightly, with never the slightest blundering,
flitting silently and easily from branch to branch."
The following astonishing story, taken from William Brewster's
Concord journal (1937), tells of a case in which antagonism of
unknown cause leads to the killing with brutal violence of a
female downy by a male:
March 20, 1911. We were in the dining-room, consulting about
the day's work, when we heard the 'tchick' note of the Downy
Woodpecker repeated almost incessantly and very rapidly just
outside. For a moment or more we paid no attention to it. But
something unusual in its quality and its insistence soon led me to
look out and this was what I saw:
On the snow, among the outermost stems of the lilacs on one
side of the dense thicket that they form was a female Downy with
extended and quivering wings. About her hopped or rather danced a
handsome male, showing the red on his occiput very conspicuously.
He kept striking at her head with his bill and occasionally he
held on for a few seconds, when the two birds fluttered about
together and perhaps rolled over once or twice, closely united. At
first I thought it an amatory encounter and I am still almost
certain that the male attempted to secure sexual contact with the
female once or twice. But if so it could not have been his primary
or at least sole object. For he continued to peck her head even
when she was lying almost motionless on the snow. For a time she
seemed to be trying to escape and for fully two minutes her cries
were piteous and incessant. At length he left her and flew up into
an elm where he clung for a moment or two, making what seemed to
me a very unusual display of the red on his occiput. Then of a
sudden he swooped down on the female, who had meanwhile been
cowering in the middle of a cluster of lilac stems, on the snow.
Dragging her forth from this slight shelter into an open space, he
attacked her again, this time with obvious fury, fairly raining a
shower of blows on the back of her head. She seemed too weak to
make any further attempt to escape and her cries, although
continued, were so faint that we could only just hear them. I now
realized for the first time that he was inspired by the lust of
killing and not by sexual ardor. It was very hard to refrain
from rushing out and driving him away but I restrained the
impulse, not being willing to interrupt a tragedy of such
extraordinary, if repulsive, interest. It would have made no
difference anyway, for this final onslaught lasted only a very few
seconds. During its continuance the male Downy seemed literally
beside himself with rage. No Butcher Bird that I have ever watched
has shown, while dealing with a Mouse or Sparrow, more murderous
energy. After finishing the foul deed he left the female lying
perfectly motionless and flew up again into the elm. We now went
out and picked up the female. She was still living but unable to
move. The [back] of her head was soaked in blood and her bare
skull showed in places. She died a little later. I skinned her and
preserved her skull which I have attached to the skin. It is punctured
in 10 or 12 places. The bird was in normal condition
physically with healthy-looking ovary, the ovules undeveloped. The
only injuries were to the skull.
Doubtless a few downy woodpeckers move southward in autumn or
early in winter, especially from the northern part of the bird's
range. Dr. Charles W. Townsend in his Ipswich notes says that he
sees "evident migrants not uncommonly in October and
November." But most of our birds spend the whole year round
with us, and in autumn we may watch them as they make provision
for winter. Even before the leaves are off the trees--in September
here in New England--we may hear, day after day as we pass a
certain tree, the tapping of a downy woodpecker where, invisible
from the ground, high up on a branch, it is digging out a cavity,
its roosting hole, in which it will sleep alone through the long
winter nights, and into which it may retreat in the daytime
whenever "the frost-wind blows."
Downy Woodpecker*
Picoides pubescens [Northern
Downy Woodpecker]
Contributed by Winsor
Marrett Tyler
*Original Source: Bent,
Arthur Cleveland. 1939. Smithsonian Institution United States
National Museum Bulletin 174: 52-68. United States Government
Printing Office
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