HABITAT SELECTION BY JUVENILE BARRED OWLS DURING DISPERSAL IN COASTAL CALIFORNIA

Whitney A Watson; University of Wisconsin - Madison; wawatson@wisc.edu; Gavin M. Jones, H. Anu Kramer, Daniel F. Hofstadter, Nicholas F. Kryshak, Ceeanna J. Zulla, Sheila A. Whitmore, Virginia O'Rourke, John J. Keane, R. J. GutiƩrrez, M. Zachariah Peery

The range expansion of the Barred Owl (Strix varia) into western North America over the last century has emerged as a major threat to the Northern Spotted Owl (S. occidentalis caurina) and likely to other western forest species as well. A better understanding of Barred Owl natal dispersal, one of the primary driving mechanisms of range expansion, is needed for the implementation of effective management. Our research team attached satellite-GPS tags to juvenile Barred Owls in the Coastal Redwood Region of northern California to characterize their habitat use as they disperse from natal territories. These tags allow for fully remote tracking of owls and have the potential to provide locations up to 1.5 years past the date of deployment, making this study the first of its kind. We collected location data from 31 Barred Owl juveniles during dispersal and conducted a multi-scale habitat selection analysis to identify landscape features which juvenile Barred Owls are using. We found evidence for selection of shorter forest stands, drainages, and areas of relatively lower elevation. Our findings have implications for understanding patterns of Barred Owl spread and identifying potential dispersal corridors, and thus for managing further spread and recolonization of removal areas.

Birds I: Owls   Student Paper InPerson Presentation