BROAD-SCALE MONITORING FOR BROAD-SCALE CHALLENGES: BIOACOUSTICS AND THE CALIFORNIA SPOTTED OWL.
Connor M. Wood; University of Wisconsin-Madison; 1630 Linden Drive, Room 208, Madison, WI, 53706; (847) 513-2240; cwood9@wisc.edu; M. Zach Peery
Understanding the influence of broad-scale ecological processes on threatened species and communities requires commensurate sampling. Yet implementing such methods can be challenging. The California spotted owl faces an array of such threats, notably the risk of large, severe fire, habitat modification, and the invasion of the barred owl. In 2017 and 2018 we conducted passive acoustic surveys across the northern Sierra Nevada (>6,200 km2). We then pursued three objectives: 1) evaluate the potential of acoustic surveys for long-term, landscape-scale population monitoring with a power analysis parameterized with field data; 2) assess coarse- and fine-scale spotted owl habitat associations across an unprecedented area with multi-scale occupancy models; and 3) explore different bioacoustic analyses to extract nuanced ecological information that goes beyond simple occupancy. Preliminary results indicate that acoustic monitoring has the power to detect small (2%) annual population changes across broad spatial scales; that spotted owl site occupancy is approximately four times greater than barred owl occupancy in the study area (0.43, 0.09); and acoustic monitoring can be used to assess pair status and possibly individual identity. These results suggest that we can meet critical information needs for threatened species using an approach with vast potential for community ecology.
Ecology and Conservation of Birds III   Student Paper