LEWIS WOODPECKER
By Lewis Young
Named for Captain Meriwether Lewis, who first
scientifically described them during the 1804-1806 Lewis
& Clark Expedition, Lewis’s woodpeckers are unusual in
that much of the year they feed mostly by catching
insects in acrobatic flight. They swoop out from a perch
like a flycatcher or circle in the air like a swallow to
catch insects.
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The Lewis’s woodpecker may be identified by its
distinctive colors, flight pattern, and behavior.
Although dark overall at a distance, upon closer
inspection the adults are very distinctive, with a
greenish-black back and head, pinkish belly, pale gray
collar and breast, and a dark red face. The wings and
tail are all dark without any white patches or spots.
Males and females are similar in appearance. Juveniles
lack the collar and red face, and the belly may be only
faintly pink.
At 10 ¾ inches long with a 21-inch wingspan, the Lewis’s
woodpecker is only 1½ inch longer than the common Hairy
Woodpecker but has a 6 inch greater wingspan. The long
wings make deep, slow beats, resulting in a more buoyant
flight than most woodpeckers and when combined with the
occasional glide, the overall flight pattern and dark
coloring can result in them being mistaken for a crow or
jay. Unique to woodpeckers in our area, their frequent
short flights from a perch to capture flying insects are
another good clue to their identification. They are
somewhat social and may form loose groups.
The range of this species covers much of the west, but
its distribution can be patchy and inconsistent from
year-to-year. The breeding range overlaps the range of
Ponderosa Pine in North America, from southern British
Columbia into southern New Mexico and from eastern South
Dakota to the Pacific Coast. Lewis's woodpecker winters
generally in the southern half of its breeding range.
The distribution of this species has been reduced,
especially in western British Columbia, western
Washington, and southern California, but its range has
expanded into southeastern Colorado, most likely because
of habitat changes that include the presence of mature
cottonwoods and corn. In the Flathead Valley and
northwest Montana they are occasionally found in spring
and summer and rarely in fall and winter. In fact, they
are rarely found anywhere in Montana during winter.
Christmas Bird Count records for Montana show only a
handful of records and several of them from the
Bitterroot Valley. Locally, none have been reported for
the Bigfork or Kalispell counts and 1 for the Eureka
count.
Lewis's woodpecker permanently inhabits the southern
half or more of its breeding range, but northern
populations, like in northwest Montana, begin to migrate
toward winter ranges in late summer. Usually traveling
in flocks of a few to 150 and always moving slowly at
low altitudes (10 to 500 feet), these migrants do not
appear to follow traditional routes, but rather move
through areas with the best food supplies. Migrants
arrive on their wintering grounds in mid-fall and depart
in March or April.
Lewis's woodpeckers breed in open forests of pine or
cottonwood with ground cover, snags, and insects.
Ponderosa pine forests are preferred at higher
elevations, while riparian woodlands dominated by
cottonwoods are preferred at lower elevations. Burned
pine forests are also used and appear more productive
for the woodpeckers. Winter sites are usually oak
woodlands or commercial orchards and are chosen for
available food storage places.
Diet varies by season and includes insects, acorns and
other nuts, fruit, and cultivated corn. They capture
insects from the air, the vegetation and on the ground.
The Lewis’s rarely excavate trees for wood-boring
insects, but often fly after ants, bees, wasps, beetles,
and grasshoppers. When insects are abundant, they hide
the surplus. In fall and winter, they store broken nuts
and grains in crevices of bark or cracks in telephone
poles or fence posts; individuals protect their own
cache, though several woodpeckers may use the same tree,
pole, or post for storage.
Nesting begins in mid-spring, earliest in the southern
and latest in the northern part of its range. Pairs
appear to be monogamous and may re-form each year on the
same territory, which the male defends with calls like
the rapid "churr." Drumming is done only during
courtship and is described as a weak roll followed by
several taps. A raised wing display flashes the male's
pink underparts to attract his mate and to warn
intruders. Nesting is sometimes colonial.
The pair excavates a hole or refurbishes an old one in a
large decaying tree, usually pine or cottonwood. Over a
lining of wood chips, the female lays an average of 6-7
white eggs that hatch after only 12-16 days. The adults
share incubation during the day but only the male
incubates at night. Naked, blind, and unable to regulate
their own temperature, the hatchlings require constant
care. In about a month, the young leave the hole, and
within a day or two, take their first flight. After
another week or so of feeding, the family joins flocks
of other woodpeckers until winter, when individuals and
pairs maintain their own food supplies.
The population and habitat status of Lewis’s woodpecker
is of concern. Based on data from the Breeding Bird
Survey and the Christmas Bird Counts, the population may
have declined by more than half between the mid-1960's
and 2005. The Lewis’s woodpecker is on Audubon’s
Watchlist, listed as “Imperiled” in British Columbia,
Canada, and of “Special Concern” in several western
states. A close association with open-canopy forests
(ponderosa pine and cottonwoods along rivers) has made
Lewis's Woodpecker susceptible to habitat loss and
degradation.
Although Lewis’s woodpeckers are not common in northwest
Montana in the spring and summer, persistent searching
in areas with numerous large cottonwoods near open
fields or meadows can pay off with a good look at these
strikingly colored birds and a chance to see their
unusual flycatching behavior
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