A minimum of 274 spotted owls, representing 199 pairs, were located most frequently in dense conifer forests at elevations from less than 100 to 7,600 feet. Dominant tree species varied from one geographic area to another. Redwood and Douglas-fir were dominant at sites along the north coast, canyon live oak and ponderosa pine along the south coast, and a mixed conifer forest in the Sierra Nevada Mountains. Trees at spotted owl sites usually were greater than 21 inches d.b.h., displayed a moderate degree of decadence, and formed a canopy where the closure was greater than 40 percent at 90 percent of the sites. Spotted owls commonly were found in canyon situations, frequently on a north-facing slope. Water was found within 0.2 miles of the spotted owls located at 90 percent of the sites. Spotted owls were found in park or suburban areas where human activity was great at 14 percent of the sites. Logging was known to have occurred at or near 71 sites. Owls occurred in some logged areas and in areas of human activity where there was still ample and dense forest and "escape" areas for the owls. Where logging was more extensive, spotted owls may have been extirpated. In other areas logging may reduce the number of pairs of spotted owls in an area. The degree of reduction may depend on the timber type. Management recommendations were suggested to gain further detailed information on habitat use by spotted owls, and to maintain present populations if land management agencies wish to do so.
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