CHARACTERIZING BARRED OWL NATAL DISPERSAL ON THE CALIFORNIA COAST

Whitney A Watson; University of Wisconsin - Madison; wawatson@wisc.edu; 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 not only to northern spotted owls (S. occidentalis caurina), but to many other species. 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 in order to characterize their movement, survival, and 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 our study the first of its kind. We have been following 31 juvenile barred owls tagged in summer 2020 and 2021. Preliminary data have revealed the capacity for juvenile barred owls to move up to 146 km from their natal territory as they disperse, and that dispersing greater than 50 km is common. Survival rates and habitat use, including use of post-wildfire landscapes, during dispersal will also be discussed.

Barn and Barred Owl Ecology   Student Paper InPerson Presentation