Consequences of Contrasting Foraging Conditions for Little Auks in the Greenland Sea

Pomona College, Claremont CA

Investigators

Abstract

P.I.: Karnovsky Proposal Number: ARC-0612504 Little Auks (Alle alle) are small planktivorous seabirds that migrate to the high Arctic to breed along the eastern shores of Greenland and the western shores of Spitsbergen and to feed in the Greenland Sea. The Greenland Sea is characterized by contrasting currents that originate from either the Arctic Ocean or the Atlantic Ocean. Therefore the Little Auks foraging along the East coast of Greenland, forage in cold, Arctic water, and are able to find large, lipid-rich copepods that came from the Arctic Ocean (Calanus hyperboreus). Little Auks finding food close to their colonies on the southwestern side of Spitsbergen, forage in water that has been influenced by warmer Atlantic water. They consume the smaller, less energy-rich copepod, Calanus glacialis. The purpose of this study is to determine the impact that these contrasting oceanographic regimes have on the foraging and reproductive behavior of Little Auks. In particular, these scientists will test hypotheses based the prey that are available in the different environments, because prey that Little Auks from the two regions bring back to their chicks will differ in species composition and energetic content. They also hypothesize that Spitsbergen chicks will grow slower and will fledge at lower weights than Greenland chicks, and that reproductive success and adult survival will be higher in Greenland birds than in Spitsbergen birds. Little Auks provide an excellent opportunity to directly observe the influence of contrasting foraging conditions on the same species of bird. Understanding the responses of Little Auks to the water masses adjacent to their colonies will increase the understanding of the roles of perturbations, such as increases in warmer currents in the Greenland Sea, will impact energy flow to upper trophic predators such as the Little Auk. These results will be useful in making predictions about responses of Arctic marine predators to changes in climate. This study is based on an earlier project where French, Norwegian, and Polish collaborators participated in the first multi-site study of Little Auks during the summer of 2005. This proposed study will also contribute to the ongoing international effort investigating the influence of oceanographic conditions on Little Auks in the Arctic. In 2006, collaborating institutions will be primarily CEPE-CNRS and the French Polar Institute as well as the Polish Academy of Sciences, and the Norwegian Polar Institute. During 2004 and 2005, the research associate who will lead the Greenland field component of this study, established an excellent working relationship with the Inuit community near the Little Auk colony in East Greenland. She has visited the school to speak to the pupils, and school children from Ittoqqortoormiit will visit the site to observe and participate in the Little Auk research during the 2006 field season. In addition, advanced students will be trained to continue the long term monitoring of the color-marked birds at the colony. Students from the Principle Investigator's home institution will be trained in all of the techniques used in the study and will conduct their own research projects while there. The results of this study will be published in scientific journals and presented at scientific meetings.