ASSESSING MITIGATION RELOCATION STRATEGIES FOR BURROWING OWLS IN SOUTHERN CALIFORNIA.
Colleen L. Wisinski; San Diego Zoo Institute for Conservation Research; 15600 San Pasqual Valley Road, Escondido, CA, 92027; 760-747-8702 x5727; cwisinski@sandiegozoo.org; Sarah M. Hennessy, Noelle A. Ronan, Ronald R. Swaisgood, Christopher J. Gregory, Lisa A. Nordstrom
In Southern California, western burrowing owl (Athene cunicularia hypugaea; BUOW) has experienced population declines and contraction of its breeding range due in large part to development. Passive relocation and active translocation are two methods used to avoid direct take when occupied burrows are within a planned development. However, the relative effectiveness of these relocation strategies has never been tested compared to non-relocated owls. Perhaps one of the most significant obstacles facing successful animal relocations is the problem of long-distance dispersal from the intended relocation site, which increases risk exposure and mortality rates. We evaluated the relative effectiveness of relocation with and without the addition of artificial conspecific cues (e.g. call/playback) as a conservation method for BUOW. During 2017 and 2018, 78 relocated and control BUOW across four counties were monitored throughout the year using satellite telemetry, site visits, and camera traps. For actively-translocated owls, we found that conspecific cues were associated with shorter dispersal distances, and the owls settled in sites with less exotic grass and more bare ground than either origin or release site. We discuss the implications of our findings and present lessons learned with applications for conservation and management of BUOW.
Ecology and Conservation of Birds III