Ryan Hepler The northern spotted owl, Strix occidentalis caurina, is the flagship threatened species of the Pacific Northwest.
Spotted and Barred Owl Spotted owl Spotted owl, listed as threatened under the Endangered Species Act, may be declining in the watershed. Their close relative—the barred owl—is increasing in numbers. Overview The northern spotted owl Strix occidentalis caurina is a medium sized Spotted owls mate for life and may live up to 20 years.
In western Washington and Oregon, spotted owls require large patches of moderate-elevation late-successional or old-growth forest habitat for breeding. Barred owls Strix varia are larger 21 inches than spotted owls.
They have dark plumage like spotted owls, but they have barring and streaking rather than spots on their head and back.
Barred owls are native to the eastern United States, but have expanded their population to the west coast in the past few decades, likely as a result of changes people have made to the landscape.
They first appeared in Washington in Barred owls are more aggressive than spotted owls and use a wider range of habitats, including old-growth forest, mature second-growth forest, and riparian areas. Barred owls appear to be successfully competing with spotted owls in Washington and displacing them from old-growth forest.
Status In Washington the spotted owl population steadily declined by about 7 percent per year from through There are now less than half as many spotted owls in Washington as in the s.
Inthe spotted owl was listed as threatened under the federal Endangered Species Act. Barred owl Inthe Northwest Forest Plan created a system of late-successional reserves for nesting habitat for spotted owls throughout Despite this habitat protection on federal land, spotted owl numbers continue to decline, likely as a result of continued habitat loss on non-federal land and increasing competition with the barred owl see Draft Recovery Plan for the Northern Spotted Owl pdf.
Surveys in the Watershed The majority of old-growth forest in the watershed occurs in six distinct patches.
Only four of these patches are considered large enough greater than 1, acres and at a low enough elevation below 3, feet to support breeding spotted owls. Surveys for spotted and barred owls have been conducted in the Cedar River Watershed from to Because the surveys varied in extent, location, and focus spotted vs.
It appears, however, that spotted owl numbers may be declining and barred owl numbers are increasing, mirroring state and regional trends. All of the spotted owls were detected in old-growth forests in the upper watershed. A maximum of five spotted owls were found in surveys from to The first juvenile spotted owl documented in the watershed which indicates successful breeding was inand several other juveniles were observed in the early s.
Complete surveys of all six large old-growth forest patches were conducted in and No spotted owls were found inand only a single male was found in He had previously been captured and banded as a juvenile in near Snoqualmie Pass.
Although we have searched for him in andhe was not relocated. Barred owls were detected in many of the spotted owl surveys. Only four barred owls were found during extensive surveys throughout the watershed in In anda total of 38 barred owls were detected across the lower and upper watershed and in both old- and second-growth forest.
For more information contact sally.Their close relative—the barred owl—is increasing in numbers. Overview.
The northern spotted owl (Strix occidentalis caurina) is a medium sized ( inches), dark-eyed owl. Spotted owls mate for life and may live up to 20 years.
The northern spotted owl (Strix occidentalis caurina) is one of three subspecies of spotted owl. Like all spotted owls, the northern spotted owl lives in old-growth forests.
Although it is often considered to be a medium-sized owl, the northern spotted owl ranks among the largest in North America. The northern spotted owl, Strix occidentalis caurina, is the flagship threatened species of the Pacific caninariojana.comlly listed under the Endangered Species Act in , the northern spotted owl continues to decline at a rate of about 4% throughout its range.
The Northern Spotted Owl (Strix Occidentalis) is a nocturnal, woodland owl native to the temperate rainforests of the Pacific Northwest, Western Canada, and Alaska whose survival is tied directly to the health of old growth forest ecosystems, and as such, had assumed the role of an indicator species for the health of these ecosystems.
The spotted owl (Strix occidentalis) is a species of true caninariojana.com is a resident species of old-growth forests in western North America, where it nests in tree holes, old bird of prey nests, or rock crevices. Nests can be between 12 and 60 metres (39 and ft) high and usually contain two eggs (though some contain as many as four).
It is a nocturnal owl, which feeds on small mammals and birds. The northern spotted owl is believed to have historically inhabited most forests throughout southwestern British Columbia, western Washington and Oregon, and .