Northern Spotted Owl Monitoring And Inventory, Redwood national and State Parks, 2011 Annual Report

Schmidt, Kristin

Author's executive summary: Annual monitoring of known northern spotted owl (Strix occidentalis caurina) activity centers in Redwood National and State Parks (RNSP) continued in 2011, at a reduced level. Project-level, or “compliance”, surveys were conducted for a forest restoration project, and the last year of a resource selection study using radio telemetry was conducted. The goals of the spotted owl program in RNSP are to: Determine the status of the parks‟ spotted owl population (occupancy trends); Provide information that will contribute to the overall knowledge base regarding the recovery of the sub-species; Document the presence of barred owls (Strix varia) and where possible determine social and reproductive status of barred owl territories; Protect spotted owls from harassment or harm that could be caused by park operations taking place during the breeding season. Eight spotted owl activity centers that were monitored in 2011 had the potential of being “active” (defined as being occupied by one or more spotted owls within the previous three years); 3 others that were inactive also were monitored in 2011. Seven of these activity centers were surveyed to protocol. Two were “spot checked”, that is, there were less than 3 complete visits to the activity center. Monitoring of these territories primarily focused on the 0.25-mile core area around each activity center. A radio telemetry study effectively “monitored” 2 territories. No home range inventories were conducted in 2011. Three territories in RNSP were occupied by spotted owls in 2011; 2 were occupied by nonbreeding pairs, and a single female was present in 1 territory. Compliance surveys for one project site using 13 established call points were conducted. No spotted owls were detected during compliance surveys, however, a pair of barred owls and a single barred owl were detected. If a barred owl was detected during a survey, a limited effort was made to determine its occupancy and reproductive status. There were 31 barred owl detections at 14 sites which represented an estimated 24 individuals. There was one new barred owl site documented in 2011. Barred owls continued to be a factor influencing spotted owl presence and detectability in the parks.

Northern Spotted Owl Monitoring And Inventory, Redwood national and State Parks, 2011 Annual Report

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