Testing the efficacy of deterring systems in two gull species

During recent decades, populations of some gull species have dramatically increased causing management problems; as a result of this, a number of deterring systems have been implemented. In this study, three commonly used scaring methods (visual, acoustic, falconry) were tested at a refuse dump. In order to evaluate the efficacy of the methods and, in particular, habituation occurrence, an index was developed that can be used for comparing such methods and for evaluating their employment in an integrated management protocol. Although the tests lasted for a few weeks, the analytical methodology revealed that the employed methods were effective only for short periods of time. (C) 2007 Elsevier B.V. All rights reserved.