White-Headed Woodpecker - Restricted range and dramatic habitat change make this bird Threatened in British Columbia.
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White-
Headed
Woodpecker
Restricted range
and dramatic
habitat change
make this bird
Threatened in
British Columbia.
Ministry of Environment, Lands and Parks
greatly affected by logging and by the uncommon in Washington. It is
suppression of formerly frequent somewhat more abundant in Oregon
ground fires. Since the large, thick- and California. In British Columbia it
barked pines could withstand most is a very rare breeding resident in the
Why are White-headed fires, the ground fires controlled Okanagan Valley, and of casual occur-
Woodpeckers at risk? smaller, competing vegetation. Now, rence in the Similkameen Valley and
or a number of reasons the White- many pine stands are gradually being east of the Okanagan. Its provincial
F headed Woodpecker is at risk in replaced by Douglas-fir growing up in
British Columbia. Unlike other their shade. Frequent fires also reduced
woodpeckers which feed pri-
marily on wood-boring insects,
the food source of the White-
A viable
the fire “fuel
load,” the layer of
dead pine needles
and thus Canadian population con-
sists of fewer than 100 birds.
Because of its extremely restricted
range, small population size, and
threats to its ponderosa pine habitat,
headed Woodpecker is largely
population of and dry grass ly- the White-headed Woodpecker is very
the seeds of ponderosa pine trees. White-headed ing under the much at risk in British Columbia and
This dependence on such a spe- trees. With much has been assigned to the provincial
cific food supply restricts the
Woodpeckers larger fuel loads Red List. This is the category of most
White-headed Woodpecker to the can not be under a fire sup- serious endangerment. Nationally,
distribution of this tree species. pression regime, this species has been designated as
Ponderosa pines are confined to
maintained a wildfire that Threatened by the Committee on the
the southern interior of the prov- without a well- would have con- Status of Endangered Wildlife in
ince at low elevations, and have trolled compet- Canada ().
been under extensive alterations
distributed ing vegetation The White-headed Woodpecker, its
from human activities for the past supply of mature now can become nests and eggs are protected in Canada
80 years. Finally, this woodpecker a hotter, more and the United States under terms of
is found only within a small por-
ponderosa pine. destructive fire, the Migratory Birds Treaty. In Canada
tion of the ponderosa’s range in eliminating even this protection falls under the federal
British Columbia. It is at the northern the largest trees. Migratory Birds Convention Act of 1994.
limit of its range there, and as is usual Snags needed for woodpecker nest Similar protection is provided under the
with populations at the edge of their sites are also in short supply, partly due British Columbia Wildlife Act.
range there are dramatic fluctuations in to Workers Compensation Board regu- The British Columbia population of
numbers. These factors of small popula- lations which require them to be felled White-headed Woodpeckers appears to
tion size, restricted range, narrow niche, when logging occurs, and due to have varied considerably in abundance in
and dramatic habitat change have firewood cutting in a few places. Very recent decades. About twelve birds were
combined to make this bird threatened few ponderosa pine stands are protected sighted per year in the 1960s, two to four
in British Columbia. in parks or ecological reserves, certainly per year from 1970 to 1975, and only one
The White-headed Woodpecker has not enough at present to support many or two from 1976 to the present.
probably always been rare in the prov- pairs of these threatened birds. Al- The period of maximum populations in
ince, and its populations are thought to though tolerant of human activity and the 1960s was one of mild winters. There
have fluctuated naturally in response to sometimes seen at bird feeders, a viable appears to have been a sharp decline
severe winters, forest fires or diseases resident population of White-headed about 1970, possibly resulting from a
which affected ponderosa pine seed Woodpeckers can not be maintained severe winter which caused a failure of
production. But this situation has un- without a well-distributed supply of the ponderosa pine cone crop. Such fluc-
doubtedly been made worse by human mature ponderosa pine. tuations in abundance are typical of
activities. Much ponderosa pine forest populations which occur at the northern
in the valley bottoms and on lower What is their status? limit of a species range. It is hoped that
T
mountain slopes, particularly in the he White-headed Woodpecker is the British Columbia population of
Okanagan Valley, has been permanently generally rare throughout the White-headed Woodpeckers will gradu-
displaced by urban development, northern part of its range. Authori- ally recover through local reproduction,
rural subdivisions, orchards and ties have referred to it as scarce and northward dispersal of birds from
pasture. The remainder has been rather local in Idaho and rare to Washington, or both.“chick” or a repeated “chick-ik-ik-ik.”
It also makes a rattle sound similar to
that of the Downy Woodpecker.
What makes them unique?
W
hite-headed Woodpeckers are un-
usual in their narrow distribution
range and high degree of habitat
specialization. LiketheGiantPanda
and its precious bamboo, these birds
have few options if their ponderosa
pines should be lost due to logging,
disease, or climate change. Compared
to most species of woodpeckers,
particularly those in Canada, this one
tends to rely less on insects, to nest
almost exclusively in dead snags, and to
nest relatively close to the ground.
The striking black and white plum-
age of these birds also sets them apart
from other woodpeckers, and their
rarity alone makes them much sought
after by keen birders. Prior to 1950 there
were only three documented sightings
in British Columbia (and hence
Canada); the first Canadian nest was
not found until 1967. The Okanagan
Valley offers the only realistic opportu-
What do they look like? is about the same size as its more com- nity for keen naturalists to add this
T
his is one of the most distinctive mon and widely distributed relative the species to their British Columbia or
woodpeckers in British Columbia Hairy Woodpecker. Canadian lists. Few experiences in
and not likely to be confused with Like other woodpeckers, the Canadian birding can match the first
other members of the family. Both White-headed Woodpecker is highly sight of a White-headed Woodpecker.
sexes have snow-white heads and specialized for climbing tree trunks and This was aptly summed up by the
throats which contrast sharply with digging out wood-boring insects. Cannings brothers in their book “Birds
their black bod- The bill is hard, straight and of the Okanagan Valley”: “... there is a
ies. They also Both sexes have chisel-like; the tongue is slender, surge of excitement as any tapping noise
have white wing can be extended far beyond the bill in a ponderosa pine stand is tracked
snow-white
patches which tip, and has barbs on the end for down. Will that black and white head
are conspicuous heads and drawing insect larvae out of nar- appear among the green needles, or will
in flight but are row crevices. Its skull is thick and it be just another hairy, downy, or
throats which
reduced to nar- heavy to withstand hammering over-enthusiastic nuthatch?”
row bars when contrast sharply against solid wood. To aid in
the wings are
with their climbing vertical trunks, it has two How do they reproduce?
W
folded. The sexes toes directed forward and two hite-headed Woodpeckers estab-
are easily distin- black bodies. backward (zygodactyl feet), each lish breeding territories in spring
guished by a red with sharp claws, and stiff tail which are about 100 hectares in
patch on the back of the male’s head, feathers which act as props. size in continuous old-growth
which is absent in the female. About 24 The call of the White-headed Wood- pine forest in central Oregon, but larger
centimetres in length, this woodpecker pecker has been described as a sharp (over 300 ha) in fragmented areas. Nest-ing sites are typically in open-canopied be found from mid-May to mid-June, Distribution of the White-headed
mature or over-mature forest stands and broods in nests from the beginning Woodpecker in Canada and the
United States
dominated by ponderosa pine or other of June to mid-July. Nestlings may
pine species. They are primary cavity fledge as early as late June.
nesters, which excavate a new cavity Very little is known about nesting by
each year, and may begin several holes White-headed Woodpeckers in British
before selecting one for nesting. This Columbia, and birdwatchers are urged
activity creates valuable nest sites for to be on the lookout for additional evi-
other (secondary) cavity users. dence.
For nesting, White-headed Wood-
peckers prefer dead trees, often broken- What do they eat?
I
topped snags, but also use leaning and n British Columbia and adjacent ar-
fallen snags or logs, and stumps. Nests eas the White-headed Woodpecker
are rarely in living trees. They nest is closely associated with ponderosa
closer to the ground than most cavity pine forests and relies on pine seeds
nesters, mostly in the range of 1 to 10 for sustenance, especially from late
metres above ground. The diameter of summer through winter. Insects can
their nest trees is usually over 60 centi- dominate their diet in spring and early
metres. Nest entrances are about 4 to summer. One study found that about 60
4.5 cm in diameter and circular, nest percent of its diet is pine seeds and 40
cavities 25 to 40 cm deep. White- percent is insects.
headed Woodpeckers lay three to nine Insects are obtained by excavating
(usually four or five) glossy white eggs, rotten wood and by gleaning them from
which are incubated for about 14 days bark crevices and foliage. Ants are a on. Seed production depends on the age
by both the male and female. The nes- prominent part of their insect food, and and density of the pine stands, and on
tling period is not accurately known, wood-boring beetles, spiders and fly lar- productivity of the site. Most seeds are
but is probably about 26 days. Young vae are also taken. These woodpeckers produced by old, large-diameter trees,
are fed by both parents. also “hawk” for insects on the wing. over 60 to 100 years, that are fairly
Only seven nests have ever been dis- They have been noted to forage on the widely spaced. Many ponderosa pine
covered in British Columbia, of which flower heads of the great mullein, a stands in the Okanagan area are young
five were in ponderosa pines, one in a roadside weed, for either seeds or in- and dense due to previous logging. In
Douglas-fir snag, and one in a stump. sects. In spring, White-headed Wood- others, fire control has prevented the re-
All were in the South Okanagan valley at peckers may “sapsuck” from young turn of nutrients to the soil. These situa-
elevations of 450 to 600 m. One had four trees by excavating sapwells in concen- tions result in poor cone crops.
fresh eggs on 10 June. In British Colum- tric rings up and down the tree trunks.
bia it is estimated that eggs could They are also attracted to suet in bird Where do They Live?
feeders, and drink frequently
T
he White-headed Woodpecker has
Present distribution of the White-headed from puddles, springs or creeks. a restricted distribution, confined
Woodpecker British Columbia One U.S. study recorded flights of to a narrow belt of dry, pine-domi-
over 5 kilometres from nest sites nated mountains and valleys from
to forage on locally abundant extreme southern British Columbia to
spruce budworms. southern California.
Cone production by ponderosa In British Columbia, the few breed-
pines is quite variable, good seed ing records are confined to the southern
crops often being five or more Okanagan valley, from Naramata to the
years apart. This may affect year U.S. border, particularly in the Vaseux
Kamloops to year abundance of White- Lake and Anarchist Mountain areas.
headed Woodpeckers in British Confirmed sightings have been made
Columbia where this is the only north to the Vernon area, at Manning
suitable pine for them to forage Provincial Park, in the Similkameen andKettle River valleys, and in What can we do?
T
the vicinity of Castlegar and o date in British Columbia
Creston. Possible sightings there have been no habitat
have been reported near management activities
Lytton and Cranbrook. It is a aimed directly at impro-
resident (non-migratory) bird ving the lot of the White-headed
within this range, and has been Woodpecker. The main need is
sighted in all seasons. to improve and sustain the sup-
The White-headed Wood- ply of ponderosa pine trees of
pecker is an excellent example cone-bearing age. Although it
of a species that is dependent may be desirable to increase the
on only one or a few kinds supply of nesting snags as well,
of trees for its survival: the recent fluctuations in wood-
ponderosa pine in the north- pecker numbers suggest that
ern part of its range and the re- food rather than nest sites is the
lated Jeffrey and Coulter pines limiting resource.
in California and Nevada. This Every effort should be
is undoubtedly because of the made to establish additional
importance of the seeds of parks or reserves in the
those trees in the woodpecker - ponderosa pine zone. However,
. Leah Ramsay photo
diet. Although they frequently it is unlikely that enough re-
nest in ponderosa pines, a vari- serves could be acquired to
ety of trees will serve as nest sites. Re- sightings in British Columbia, 85 per- maintain viable woodpecker pop-
searchers have emphasized that this cent have been in ponderosa pine ulations. Most White-headed Wood-
woodpecker is so partial to mountain forests, 5 percent in ornamental peckers will probably continue to be
slopes covered with ponderosa pine plantings, and the remainder in other supported on Crown lands or large pri-
“... that it is almost useless to look for forest types. Since nesting is usually in vate parcels managed for timber pro-
it elsewhere.” Of over 100 recorded decadent trees and foraging in living duction; therefore integrated forest
trees, stands having both components management is the most logical means
are important. In Oregon it has to improve their
been calculated that the density of Of over 100 habitat. This will
large-diameter snags (dead trees) be best for the
should be at least 550 per 100 ha
recorded birds if the objec-
of forest to support maximum sightings in tive is to achieve
nesting densities. That is the high- relatively open
est snag density requirement for
British stands (20 to 25
any Oregon woodpecker. Snag Columbia, percent canopy
needs in British Columbia are density) contain-
expected to be similar.
85 percent ing many large
Scattered ponderosa pine trees, have been in old ponderosa
usually mixed with more abun- pines and pine
dant Douglas-firs, are fairly
ponderosa snags. This does
widely distributed in the warm, pine forests. not rule out log-
dry valleys of southern British ging. Logging can
Columbia. But sizeable stands domi- serve to thin dense stands nearing
nated by predominantly mature pines maturity, and to remove competing
are discontinuous and scarce, partly trees like Douglas-fir or lodgepole pine.
accounting for the very limited distri- Thinning reduces the danger of high
- - bution of White-headed Woodpeckers intensity crown fires which destroy
.
David F. Fraser photo in the province. mature pines, and can allow the re- - . -
Steve Cannings photo . Leah Ramsay photo
sumption of ground fires to which for this species. Where snags are in short which are also confined to that area.
ponderosa pine stands are historically supply they can be created by girdling a Cutting down large ponderosa pine
adapted. Surface fires remove compet- few live trees. Snags need not be trees, even dead ones for firewood,
ing vegetation which helps to maintain ponderosa pine (although these are pre- should be avoided. People are urged to
the dominance of ponderosa pine, and ferred); densities of about four or five search for these delightful birds and to
also release nutrients into the soil – snags per hectare are ideal for White- report any sightings, and particularly
nutrients which are needed to stimulate headed Woodpeckers. nests, to the nearest BC Environment
cone production. The public can help White-headed office. People with residences adjacent
Selective cutting is much preferred Woodpeckers by encouraging the to ponderosa pine woods may be re-
over clear-cutting in White-headed implementation of beneficial forest warded by appearance of this rare
Woodpecker habitats. However, small, management practices, and by applying species at their feeders, particularly if
scattered clearcuts on a very long rota- them on their own woodlots. More suet is part of the menu.
tion (e.g. every 180 years) could main- reserves containing old-growth White-headed Woodpeckers may
tain sufficient trees of cone-bearing age, ponderosa pines are also badly needed be on the verge of extinction in British
that is, over 100 years old. in the Okanagan area and would benefit Columbia and need all the help
Retention of naturally occurring a host of other rare wildlife species they can get.
snags and stubs for potential nest sites is
important when logging occurs. If they
are a safety hazard for forest workers,
they can be “high-stumped” 3 or 4 m
above the ground and still be suitable
- , :
Wildlife Branch
BC Environment
Ministry of Environment, Lands and Parks
Parliament Buildings
Victoria, British Columbia V8V 1X4
Forest Renewal British Columbia
--- .
. ,
David S. Fraser photo
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