Mapping isotopic signature and trophic niche in relation to individual migration strategies of an Arctic seabird

The main objective of my MSc thesis is to investigate stable isotopes as indicators of trophic niche and diet in relation to individual migration strategies in an Arctic seabird. Little information exists on individual flexibility in migration- and winter foraging strategies of seabirds breeding in Svalbard. Such information is important for conservation management and for understanding how seabird populations might be influenced by, and respond to, changing conditions on wintering grounds. I will use Arctic skuas breeding in Kongsfjorden as a study model. When they leave the breeding area in autumn they migrate and stay away from Svalbard for 8 months, until they return for the next breeding season. The big question is where do they go and what do they eat? Arctic skua migration has been tracked with geolocators since 2009 in the Birdmap project. It has revealed that individuals target different wintering areas, located far apart. The aim of this study is to investigate the winter diet of the Arctic skua and whether it depends on wintering areas and to what degree it is consistent or flexible over years. Furthermore, I will test for so-called carry-over effects and whether winter diet affects spring migration and subsequent reproductive performance.