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 Downy
Woodpecker
Woodpeckers are a family of birds sharing
several characteristics that separate them from other
avian families. Most of the special features of their
anatomy are associated with the ability to excavate wood.
The straight, chisel-shaped bill is formed of strong bone
overlaid with a hard covering and is quite broad at the
nostrils in order to spread the force of pecking. A
covering of feathers over the nostrils keeps out pieces
of wood and wood powder. The pelvic bones are wide,
allowing for attachment of muscles strong enough to move
and hold the tail, which is so important for climbing.
Another special anatomical trait of woodpeckers is the
long, barbed tongue that searches crevices and cracks for
food. The salivary glands produce a sticky, glue-like
substance that coats the tongue and, along with the
barbs, makes the tongue an efficient device for capturing
insects.
There are 198 species of woodpeckers found throughout the
world, 13 of them occurring in Canada. The smallest and
perhaps most familiar of the species found in Canada is
the Downy Woodpecker. It is similar in appearance to the
larger Hairy Woodpecker. Both are black and white with a
broad white stripe down the back from the shoulders to
the rump. The wings are checkered in a black and white
pattern that shows through on the wings' undersides, and
the breast and flanks are white. The crown of the head is
black; cheeks and necks are adorned by black and white
lines. The males of both species have a small scarlet
patch, like a red pompon, at the back of the crown.
Although they look very much alike, the Downy and the
Hairy Woodpecker have distinguishing characteristics. The
Downy's outer tail feathers are not all white as are the
Hairy Woodpecker's, but are barred with black. The Downy
is about 6 cm smaller than the Hairy, measuring only
15-18 cm from the tip of its bill to the tip of its tail.
And the Downy's bill is shorter than its head, whereas
the Hairy's bill is as long as or longer than its head
length.
Male and female Downy Woodpeckers are basically the same
size, weighing in the range of 22-33 g. The females have
a longer tail and slightly shorter bill.
Like most woodpeckers, the Downy is a climber. Its short
legs and two toes pointing forwards and two backwards on
each foot give the bird an excellent grip for climbing.
It climbs by propping its stiff, sharply pointed tail
feathers against the support while shifting its leghold.
With its body close to the trunk or branch and its head
bobbing, the bird "hitches" upwards, backs down
spiraling, and nimbly darts sideways at incredible speed.
Distribution
The Downy Woodpecker occurs over the greater part of the
North American continent, from the Gulf States
northwards. In Canada in the northernmost part of its
range, it is found from Newfoundland across to James Bay,
the northern Prairie Provinces, the southern Mackenzie
District of the Northwest Territories, northern British
Columbia, and the Yukon. Downys in the northern parts of
the range migrate southward in the winter, but these
migrations are somewhat irregular, depending on the
available food supplies.
Downy
Woodpecker Range Map
Habitat
Woodpeckers live where trees grow. The Downy Woodpecker
is at home in a variety of wooded areas across its range,
in the northern mixed forests and in the deciduous
(broad-leaved) forests farther south, in woodlots and
parklands, in orchards, and even in the parks and avenues
of suburb, town and city. It prefers places where
broad-leaved trees, such as poplars, birches and ashes,
let in the light among the evergreens. Forest edges and
areas around openings in the denser forests are also
favored places. In the western part of its range it can
be found in alder and willow growth. The Downy shares
these habitats with other kinds of woodpeckers, but there
are differences in their selection of nest sites and in
their choice of food. Each species thus occupies its own
niche in the environment.
Breeding
Downy Woodpecker pairs often return to the same nesting
area of approximately 2 ha every year of their adult
life. Male and female Downys sometimes occupy separate
sleeping holes in the trunks of trees, and they may even
select the same sleeping holes they had excavated in a
former season.
As early as February or March a Downy Woodpecker pair
indicate occupation of their nesting site by flying
around patrolling it and by drumming short, fast tattoos
with their bills on dry twigs or other resonant objects
scattered around the territory. The drumming serves as a
means of communication between the members of the pair
and informs other Downys of their occupation of the land.
Downys also have a variety of calls. They utter a "tick,
tchick, tcherrick," and both male and female
add a sharp whinnying call during the nesting season.
During the breeding season Downy Woodpeckers defend their
territory against trespassers of their species.
Encounters with intruders result in hostile displays: the
opponents parade in front of each other in threatening
poses, bills gaping, wings raised and fully opened, the
birds twisting and turning like small windmills. The
Downy male engages the male trespassers and the female
the females, while their respective partners look on.
These demonstrations may go on for several hours but
seldom end in actual fighting. Usually the intruder is
chased away or simply disappears.
After establishing their territory the Downy pair look
for a suitable tree in which to excavate their nest
cavity. They are especially attracted to dead trees or
stubs dotted with old holes from former nestings. They
may start several holes in different trees before the
final choice is made, usually by the female. The entrance
hole may be anywhere from 1.5 to 18.0 m above the ground,
but is usually from 3.6 to 9.0 m.
The pair require about two or three weeks to excavate
their nest hole, which has the form of a flask 12-15 cm
wide and about 20-30 cm deep. The entrance is through a
short narrow neck at the top.
The male does most of the drilling. He spends nearly half
of the daylight hours each day working on the hole in
average sessions of about 20 minutes, resting and feeding
in between. First he chisels out the passage, making it
just wide enough for himself and his mate to squeeze
through. Laboriously he taps and digs out the walls of
the cavity, widening and deepening the room inside and
throwing the loose chips out over his shoulder. When the
hole is deep enough to allow him to turn around inside,
he brings the chips out in his bill and scatters them
with a shake of the head. Henceforth he usually sleeps in
the cavity at night.
The female occupies herself flying around, feeding, and
chasing intruders. When the nest hole nears completion,
she becomes more interested in it and begins to work on
it diligently. The pair devotes most of their free time
to courtship involving calling and drumming, pursuits and
displays.
The female Downy Woodpecker usually lays four or five
white eggs and occasionally six or seven. During the egg
laying, male and female take turns guarding the nest by
sitting in the doorway.
After incubation of the eggs starts, the birds take turns
warming them during the day in shifts lasting from 15 to
30 minutes. Most changeovers take place directly and
immediately at the nest. At night the male remains on the
eggs alone while the female sleeps elsewhere. In this
manner, the eggs are covered nearly all of the time
during the Downy Woodpecker's 12-day incubation period.
The young
When the young woodpeckers hatch, they are tiny helpless
creatures, almost naked, sprawled at the bottom of the
cavity. For a few days the parents warm the nestlings as
they did the eggs and occasionally bring them small
insects for food.
As the nestlings grow, the parents gradually stop
brooding and spend more time collecting food for their
young. When the parent arrives with food in the bill
there is a swell in the nestlings' chippering noises from
within the nest. The parent dives headfirst into the
cavity and touches the swollen corner of a nestling's
mouth with its bill. As the mouth springs open, the
parent pushes the meal down the nestling's throat. And
while the nestling subsides, the parent picks up a
dropping and flies away with it.
Thus the nestlings are fed and their nest is kept clean
until they are 17 or 18 days old, when they are almost
fully grown. They look like their parents, except that
the crowns of the young males are tinted red or rust-red
or pinkish, and those of the females are striped or
dotted with white. The young ones are now able to crawl
up the walls of the cavity and take turns sitting in the
doorway, looking out. To meet the nestlings' increasing
demands for food, the parents bring large meals about
every three minutes. Each of four nestlings is therefore
fed four or five times in the hour.
As the time approaches for the young to leave the nest
the parents slow down the feedings, making the nestlings
livelier and hungrier. The one in the doorway pops in and
out with great vigor and calls loudly, but is in no
hurry. Almost a day passes before the fledgling, now as
large as its parents and spotlessly clean, pops out far
enough to spread the untried wings. Once outside it is
able to fly quite a distance before it achieves a safe
landing.
When the fledglings are all out, they hide among the
green leaves in the tall trees and call for the parents
to come and feed them. Within a week they begin following
the parents, begging for food with sharp calls and
flapping wings. At the age of three or four weeks the
young birds are fully capable of looking after
themselves. It is at this stage in the life cycle that
mortality is greatest, when the young are out of the nest
and no longer protected by the vigilance of their
parents.
Molt
The adult birds begin to molt their worn and dirty
plumage while the young are still in the nest. The
strong, central pair of tail feathers is molted only
after all the other tail feathers have been replaced.
This ensures that the woodpecker's climbing ability is
not hampered during the molting period. The complete molt
takes about two months, during which time each bird keeps
much to itself, resting and feeding. When the molt is
over in September, the Downy Woodpecker emerges with the
white part of its fresh winter plumage showing a faintly
yellow tinge that eventually is lost by wear.
The young Downy Woodpeckers also shed their juvenile
plumages. Their molt starts in late summer and ends in
full adult plumage. Their crowns are jet black, and at
the back of the head the young males wear the bright red
spot of the adult.
Food and feeding
In the spring and summer the Downy Woodpecker feeds on
free-flying and hidden insect life, as it becomes
available. After the young hatch, the need to select food
suitable for the nestlings at various stages of growth
and gradually to increase the speed of the feedings
compels the Downy Woodpecker to seek larger and more
easily caught prey, such as caterpillars, mayflies, and
moths. It also takes small wild fruits in season.
After the nesting season, the Downy Woodpecker resumes
its specialized feeding habits. It hunts down myriads of
small insects and larvae that infest trees and lie hidden
in cracks and crannies along branchlets, twigs, and down
the trunk. The Downy's small size enables it to hunt
along the upper branches of trees, while the larger
heavier woodpecker species concentrate on more solid
areas such as the trunk.
Unlike some other species, such as the Red-headed
Woodpecker, Downy Woodpeckers do not cache food for
winter. During the winter a pair of Downy Woodpeckers may
do a thorough job of ridding an infested tree of tiny
scale insects. With its sharp bill boring small round
holes or prying open the insects' hiding places, the
woodpecker fetches out its food with its long agile
tongue. Often the birds spend most of the daylight hours
going over areas of good yield in the same trees, until
they retire just before sunset, each to its own sleeping
hole in the trunk of a tree.
Enemies
The woodpecker's first response to danger is to use a
tree trunk or branch as a shield. Many a Downy Woodpecker
has saved itself from the grasping talons of a hawk or
the claws and bill of a shrike by dodging swiftly
sideways behind the trunk of a tree.
Nestlings raised in holes are, of course, much safer than
those in open nests. The narrow entrance to the Downy
Woodpecker's nest, hewn to size, protects both the adults
and the young from practically all predators except
snakes. Even a squirrel, scratching and gnawing at the
soft wood to get at the fledglings within, has little
chance of getting past the watchful defender sitting in
the passage way, its awl-like beak at the ready. But, if
a Downy is caught at night behind a rotting doorway by
some tree-climbing marauder, its fate is sealed.
From a human viewpoint, few wild birds have a record as
irreproachable as that of the Downy Woodpecker. Its sober
ways and its pest-killing activities merit our respect
and attention.
Visit Shaw Creek
Bird Supply to see our selection of Woodpecker
Feeders
and Downy
Woodpecker House.
Copyright © 2003 Shaw Creek
Bird Supply
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