Territory size and habitat selection of breeding Common Cranes (Grus grus) in a boreal landscape

Abstract

Information on how birds use different types of habitat and move within landscapes is crucial for avian ecology, conservation andmanagement. The Common Crane Grus grus has the widest distribution of all crane species and covers both increasing and decreasing populations. Ecological knowledge is therefore necessary both for conservation and to mitigate bird-human conflicts.We studied territory size and habitat selection of breeding Common Cranes (n = 11) at two spatial scales in south-central Sweden by using VHF and GPS transmitters. Breeding families of Cranes were strongly associated with farmlands and wetlands independent of spatial scale. However, 41% of positions were within forested habitats.According to a compositional analysis,moist andwet forestswere selected more frequently than dry forests. Territory size was on average 250 ha ± 47.8 SE. The territories showed little overlap between neighboring breeding pairs.Our study provides information necessary for estimating densities of breeding pairs, but also to indicate habitat types worth special attention by landscape managers and conservationists.