Response of burrowing owls to experimental removal of satellite burrows

Abstract

Studies of habitat relationships indicate that burrowing owls (Athene cunicularia) often select nest sites with multiple burrows. This behavior may increase survival of post-emergent nestlings. We experimentally blocked access to burrows within 20m of nests (satellite burrows) within a large grassland in central California to evaluate the response by year-round resident burrowing owls to removal of satellite burrows. We compared reproductive performance and nest fidelity between owls whose access to potential satellite burrows was blocked and owls whose nests had similar numbers of naturally occurring burrows within 20m of the nest prior to manipulation. Adult owls and their young moved away from treatment nests, but reproductive rates between owls from treatment and control nests did not differ. Movements involved the entire family, occurred before young had fledged, and owls did not return to the natal nest burrow. Movements ranged from 25m to 120m and occurred at 5 of the 7 treatment nests with young. No such movement occurred at any of the control nests. Our findings support results from correlational studies that multiple nearby burrows influence nest site selection. 2014 The Wildlife Society