Factors affecting escape distances of staging waterbirds

Abstract

Abstract Escape distances (EDs) have been used to study sensitivity of waterbirds to different sources of disturbance, to design reserves for waterbirds, and to define eco-targets for the Wadden Sea management plan. However, the use of ED as an index of sensitivity has been criticised because it can be highly variable. Although some factors affecting variation in the EDs of species have been studied, there is still a need for further analysis of factors that may affect it. In this study, we analysed the EDs of 19 waterbird species (geese, ducks, waders and gulls) exposed to a walking person (N = 1,371) during autumn and spring 1980–1984 under controlled conditions in the Danish Wadden Sea. We analysed how EDs varied between species in relation to body mass and hunting and within species in relation to flock size and weather conditions. EDs increased significantly with species body mass, and quarry species (dabbling ducks, curlew Numenius arquata, golden plover Pluvialis apricaria, common gull Larus canus ...