Waste disposal sites, an all-you-can eat buffet for Carrion Crows (Corvus corone) (#853)
Many corvid species are considered as nuisance animals, especially in dense populated areas and cities. In Austria, particular carrion and hooded crows are regarded as pest birds that frequently cause damage to crops, feed on human waste and strew trash. A widely used control method for the increasing anthropophilous corvid species with debatable evidence for its effect is hunting. To evaluate the population density of carrion crows (Corvus corone)over the course of one year in relation to potential anthropogenic food resources and reference areas we conducted a detailed field survey in the Austrian rhine valley. Our results demonstrate that habitat choice and density of carrion crows are predominantly influenced by the number of and distance to waste management facilities, feedings of game animals, agricultural used areas and its capacity value. In the area of biogas-, green- and house waste disposal sites a higher individual density was recorded. With increasing human population density the probability to observe more than two carrion crows at a survey site decreased. Despite the continuously increasing number of hunting-kills in the past 25 years a rise in population size was registered. Based on this study, an area-wide comprehensive waste management plan is regarded as beneficial strategy. We discuss decimation in anthropogenic food supply as long-term and sustainable management suggestion to reduce and stabilise the population density of carrion crows in light of their behavioural and reproductive biology.