The male northern spotted owl was last detected 6 August 2002, near Highway 62. The following morning a pile of adult northern spotted owl feathers was located and a goshawk was observed nearby. It has been speculated that the juvenile and adult male from the Castle Creek site are dead, and the fate of the female is unknown (NPS, CRLA 2002). The presence of the adult male near Highway 62 West was thought to be the result of displacement from the nest tree by the barred owl and/or the goshawk.
The park is considered at the eastern edge of the northern spotted owl range; however, habitat, sightings, and nesting has occurred within park boundaries (Crater Lake National Park, FMP 2002a). Approximately 32,260 acres of suitable northern spotted owl habitat has been identified in the park, and all known northern spotted owl activity centers occur in areas identified as suitable habitat. Stonum (1993 in NPS–Crater Lake National Park 2002) reported that 29 individual northern spotted owls were documented within the park following a 1992 survey of potential habitat. Tuss (1998) reported that 18 different northern spotted owls or pairs of owls were located in the park from 1994–1996. The typical timing for surveys in Oregon is from February to June (Laye pers. comm. 2002), and surveys are typically conducted during two successive years. Additional northern spotted owl surveys will be conducted at Castle Creek during 2002 to determine status. However, conclusive evidence is unlikely to be found this season and the 2003 nesting season will provide the best opportunity to prepare conclusions about the Castle Creek site northern spotted owl pair. These surveys will be resumed during May 2003, and will report any nesting or significant activity to the U.S. Fish and Wildlife Service (NPS-CRLA 2002a, USFWS 2002b).
Northern spotted owls occupy forests with moderate to high canopy closure; a multilayered, multispecies canopy dominated by large overstory trees; a high incidence of large trees with large cavities, broken tops, and other indications of decadence; numerous large snags; heavy accumulations of logs and other woody debris on the forest floor; and considerable open space within and beneath the canopy (Thomas et al. 1990 in NatureServe 2002j). Generally, such habitat conditions are found in old-growth stands (at least 150 to 200 years old), but sometimes occur in younger forests that include patches of older growth. Within Oregon, coniferous forests begin to develop conditions suitable for northern spotted owls about 80 to 120 years following clearcutting (NatureServe 2002j). In southwestern Oregon, the northern spotted owl consistently selected old-growth forest habitat for foraging and roosting (Carey et al. 1992 in NatureServe 2002j).
