Diets of Burrowing Owls (Athene Cunicularia) In a Coastal Southern California Preserve

Regionally threatened Burrowing Owls (Athene cunicularia) rely on open habitats with suitable burrows and prey. Dangermond Preserve is potentially the best remaining example of this in Santa Barbara County, and understanding owl diets and their spatial variation can guide targeted habitat management to support owl populations. We expected Burrowing Owl diets at this preserve to have a greater proportion of vertebrate prey compared to previously documented diets at a smaller recently disturbed restoration site. We analyzed the contents of 25 intact owl pellets collected from mapped burrows and determined the minimum number of individual prey based on vertebrate and invertebrate remains. Preliminary results show evidence of California voles, western harvest mice, and other small rodents, as well as European earwigs, beetles, and other invertebrates. With these diverse prey, we can understand how a site dominated by invasive flora supports burrowing owl diets may inform restoration.