Living on the edge of a shrinking habitat: the ivory gull, Pagophila eburnea, an endangered sea-ice specialist

• Published in: Biology Letters
• Main Authors: Gilg, Olivier, Istomina, Larysa, Heygster, Georg, Strøm, Hallvard, Gavrilo, Maria V., Mallory, Mark L., Gilchrist, Grant, Aebischer, Adrian, Sabard, Brigitte, Huntemann, Marcus, Mosbech, Anders, Yannic, Glenn
• Format: Text
• Language: English
• Published: The Royal Society 2016
• Subjects: Special Feature; Arctic; Canada; Greenland; Norway; Svalbard; ivory gull; Pagophila eburnea; Sea ice
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5134029/; http://www.ncbi.nlm.nih.gov/pubmed/27807248; https://doi.org/10.1098/rsbl.2016.0277

The ongoing decline of sea ice threatens many Arctic taxa, including the ivory gull. Understanding how ice-edges and ice concentrations influence the distribution of the endangered ivory gulls is a prerequisite to the implementation of adequate conservation strategies. From 2007 to 2013, we used satellite transmitters to monitor the movements of 104 ivory gulls originating from Canada, Greenland, Svalbard-Norway and Russia. Although half of the positions were within 41 km of the ice-edge (75% within 100 km), approximately 80% were on relatively highly concentrated sea ice. Ivory gulls used more concentrated sea ice in summer, when close to their high-Arctic breeding ground, than in winter. The best model to explain the distance of the birds from the ice-edge included the ice concentration within approximately 10 km, the month and the distance to the colony. Given the strong links between ivory gull, ice-edge and ice concentration, its conservation status is unlikely to improve in the current context of sea-ice decline which, in turn, will allow anthropogenic activities to develop in regions that are particularly important for the species.