Consistent variation in individual migration strategies of brown skuas

• Published in: Marine Ecology Progress Series
• Main Authors: Krietsch, J, Hahn, S, Kopp, M, Phillips, RA, Peter, HU, Lisovski, Simeon
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 2017
• Subjects: Antarc*; Antarctic; King George Island
• Online Access: https://epic.awi.de/id/eprint/52147/; https://epic.awi.de/id/eprint/52147/1/Krietsch_et_al_2017-MEPS.pdf; https://doi.org/10.3354/meps11932; https://hdl.handle.net/10013/epic.cf66e7be-f62f-4dc4-b29d-e8b474dbc2b4

Seabirds show remarkable variability in migration strategies among individuals andpopulations. In this study, we analysed 47 migrations of 28 brown skuas Catharacta antarcticalonnbergibreeding on King George Island in the Maritime Antarctic. Brown skuas from this pop-ulation used a large area during the non-breeding period north of 55° S, including parts of thePatagonian Shelf, Argentine Basin and South Brazil Shelf, areas which are characterised by highlevels of marine productivity. However, individual birds utilised only a subset of these areas,adopting 1 of 4 distinct migration strategies to which they were highly faithful between years, andshowed high repeatability in departure and arrival dates at the breeding ground. Although theyspent the majority of the non-breeding season within a particular region, almost all individualsused the same area in the late winter, exploiting its seasonal peak in productivity. Overall, theseresults indicate consistent individual variation in migration strategies that may reflect a combina-tion of genetic control and individual experience, but with considerable flexibility to shift distribu-tion in response to prevailing environmental conditions.