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Nest-Site Habitat Use by White-Headed Woodpeckers in
the Eastern Cascade Mountains, Washington
PDF Format - [467KB]
Acknowledgments
We are grateful to R Dixon for providing advice on survey and vegetation
sampling methods. T Aversa, K Bevis, C Flick, W Gaines, G Habersberger,
S Johnson, G King, P Mattocks, H Opperman, B Senturia, A Stegen, A Stepniewski,
D Swain, and K Woodruff provided information on the location of nest sites
or nest areas. C Hill and T Hill provided lodging in Klickitat County.
For assistance finding nests and collecting vegetation data we thank K
Cruce and R Torrance, respectively. J Jacobson generated the information
used for the regional geophysical assessments and also created the figures.
The manuscript was improved by comments provided by R Dixon and K Garrett.
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Nest-Site Habitat
Use by White-Headed Woodpeckers
in the Eastern Cascade Mountains, Washington
Joseph B Buchanan, Russell E Rogers, D John Pierce, and John
E Jacobson
Originally published in NORTHWESTERN NATURALIST 84:119–128
WINTER 2003
Winter 2003
Abstract: The white-headed
woodpecker (Picoides albolarvatus) is strongly associated with
old-growth ponderosa pine (Pinus ponderosa) forest, a degraded
and increasingly uncommon habitat in the Pacific Northwest. We investigated
the nest-site habitat use of this species by collecting vegetation data
at 21 known nest sites in the eastern Cascades of Washington, 12 of which
we found in 1999. Sixteen of 17 (94%) nests in the ponderosa pine vegetation
zone were in the 72% of the zone that occurred below 1219 m, and 15 (88%)
nests were on slopes of <20% (which comprised 48% of the zone); the
total area characterized by both slopes <20% and elevation below 1219
m was 181,664 ha or 33.6% of the vegetation zone. Most (16 of 21) nests
were in ponderosa pines and 81% (17 of 21) were in snags. The nest snags
and trees were generally large, with a mean diameter at breast height
of 51.5 cm (
= 5.13). The mean height of nest snags and trees was 12.6 m (
= 2.33), and the mean height of the nest cavity entrance was 5.8 m (
= 1.37). Compared to random sites located <1 km from each nest, nest
sites were characterized by a greater abundance, size, and basal area
of large trees and snags, primarily ponderosa pines. Management of habitat
for this species should include retention of 6 to 8 large snags/0.8 ha
and 8 to 10 large trees/0.8 ha in the immediate vicinity of nesting areas.
Habitat requirements at the home range scale should be investigated.
See also:
Management Recommendations
for Washington's Priority Species, Volume IV: Birds - White-headed Woodpecker
- PDF Format
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