Environmental factors in migratory route decisions: A case study on Greenlandic Arctic Terns (Sterna paradisaea)

Abstract

Identification and characterization of seasonal migration routes and stopover sites has been recognized as important to the conservation of migratory species. This project utilizes multiple regression models including circular-linear regression to identify associations between route choice, travel speed, and environmental preferences using trajectory data of migratory Arctic Terns (Sterna paradisaea) and environmental data obtained through remote-sensing techniques. Results of this study suggest that route choice on the southward post-breeding migration route may be more dependent on underlying environment than the northward postwintering migration route. In contrast, travel speed was variably associated with underlying environment between southward and northward migrations, including several differences regarding the impact of interactions between environmental variables. These results reveal the importance of using multiple metrics in the estimation of spatial resistance and highlight conflicts between the theoretical resistance framework of GIS and movement analysis methods.