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WatchList Species Account
for Spotted Owl (Strix occidentalis)
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| Photo: Clipart.com |
The Spotted Owl has received much study
in recent years because of its favored habitat and the controversies
that surround it—old-growth conifer forests with a high
commercial value. Many tracts of this habitat have been clear-cut
or otherwise exploited, bringing about the decline of the
owl. The disputes and attempts at resolution have generated
several major management plans, various reviews of the owl’s
status, several literature reviews, and a symposium. A positive
side is that the bird has served to stimulate innovative research
and more comprehensive conservation planning. It is found
from sea level to 1,200 m in the northern part of its range
and to 2,700 m in the southwestern U.S.
There are three recognized subspecies:
the Northern Spotted Owl (caurina), found in the Pacific Northwest
from British Columbia to central California, the California
Spotted Owl (occidentalis), found mainly in the Sierra Nevada
but also in the California coastal ranges from Monterey to
Santa Barbara, and the Mexican Spotted Owl (lucida), in scattered
localities in Utah, Colorado, Arizona and New Mexico and south
into central Mexico. The bird tends to select mature, old
forest stands with an accompanying selection against young
stands. It uses forests with a considerable degree of complexity
and structure in both managed and unmanaged forests. Roost
sites typically are in areas with high canopy closure and
multiple canopy layers, dominated by large-diameter trees.
These are usually cool, shady spots, and it is hypothesized
that the bird requires old-growth forest to avoid summer heat
stress. In hunting its prey, primarily rodents, it tends to
avoid flying over brushy and clearcut forest areas and recently
logged forests.
Data indicate that populations are declining.
The major threat is loss and degradation of habitat due to
clear cuts and even-aged tree management. Urban and suburban
expansion has also taken a toll. Competition and hybridization
with the closely related Barred Owl, which has arrived in
the Spotted Owl range in recent years, is also a threat to
the species. Barred Owls displace Spotted Owls and the numbers
of the former have increased considerably within the range
of the Spotted Owl in the past 25 years.
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