Should I stay or should I go? Territory settlement decisions in male Corncrakes Crex crex

Abstract

ABSTRACTCapsule: Corncrake Crex crex males shift their territories and change habitat preferences across the breeding season as a consequence of anthropogenic pressure and/or to enhance the chances of reproduction through sequential polygamy.Aims: To examine how habitat structure changed during the breeding season, whether Corncrake males responded to those changes and which habitat features were crucial when males settled and occupied territories.Methods: Calling male Corncrakes were surveyed six times during the breeding season. In each location where a calling male was recorded, the habitat and vegetation structure was described from one to three times during the season.Results: Corncrake males avoided extremely wet and extremely dry habitats, whereas large sedge and reed communities were much more preferred. There were significant seasonal changes in the density of vegetation and moisture content. Males were more sedentary at the beginning of the breeding season. Males significantly changed habitat preferences in short-periods of time. However, none of the habitat-related features explained whether males stayed or left the territory.Conclusion: Corncrakes shift their territories during the breeding season in response to anthropogenic pressure (agricultural activity) as well as changes in water levels during the year. However, territorial shifts within seasons might also be caused by the appearance of fertile females in different habitats at different stages of the breeding season.