The Influence of Land-cover Type and Vegetation on Nocturnal Foraging Activities and Vertebrate Prey Acquisition by Burrowing Owls (Athene cunicularia)

Alan J Marsh
2012
Studies of habitat selection by foraging animals assume patterns of animal presence correlate with successful foraging, without explicit evidence this is valid. I used GPS dataloggers and digital video recorders to determine precise locations where nocturnally foraging Burrowing Owls captured vertebrate prey. I compared land-cover type selection patterns using a presence-only Resource Selection Function (RSF) to a model that incorporated prey capture locations (CRSF). I also compared net prey
more » ... turns in each cover type to better measure reward relative to foraging effort. Finally, I measured vegetative conditions at foraging and random locations. The RSF method did not reflect prey capture patterns, and cover-type rankings from this model are inaccurate. Burrowing Owls successfully forage across all cover types, albeit where vegetation is relatively sparse, with highest net energy returns in native grass. Conservation efforts for Burrowing Owls should focus on ensuring heterogeneity of plant heights and densities across the landscape.
doi:10.7939/r30331 fatcat:do6ybizhcnhzvcuhgnx7i7puwa