An Estimation Of The Average Foraging Radius Of The Barn Owl Tyto-Alba Based Upon Rejection Pellets Analysis

A significant correlation between the length of the permanent water courses in a given study area and the percentage of skulls of water shrews, Neomys anomalus and N. fodiens, found in the rejection pellets of the barn owls resident in the same area, is used to estimate the average foraging radius of these nocturnal predators. In the area studied (Bas-Chablais, Haute-Savoie, French Alps [France]), the foraging radius of the barn owl averages 2.5 km.