Longer ice-free seasons increase the risk of nest depredation by polar bears for colonial breeding birds in the Canadian Arctic by Samuel A. Iverson, H

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Longer ice-free seasons increase the risk of nest depredation by polar bears for colonial breeding birds in the Canadian Arctic by Samuel A. Iverson, H. Grant Gilchrist, Paul A. Smith, Anthony J. Gaston, and Mark R. Forbes Proceedings B Volume 281(1779):20133128 March 22, 2014 2014 by The Royal Society Slide 2 Map of the study area. Samuel A. Iverson et al. Proc. R. Soc. B 2014;281:20133128 2014 by The Royal Society Slide 3 Decline in annual sea ice coverage in Northern Hudson Bay Narrows, Canada from 1988 to 2012 quantified in relation to the number of days that more than 30% of the sea surface was covered by ice each winter. Samuel A. Iverson et al. Proc. R. Soc. B 2014;281:20133128 2014 by The Royal Society Slide 4 Summary proportions for the frequency with which one or more polar bears was observed during the nest incubation period [BearDay] at the East Bay Island common eider colony (red symbols) and Cape Pembroke thick-billed murre colony (blue symbols) in relation... Samuel A. Iverson et al. Proc. R. Soc. B 2014;281:20133128 2014 by The Royal Society Slide 5 Probability of encountering polar bear sign (blue lines) or fox sign (red lines) on islands with common eider colonies in relation to (a) the number of eider nests, (b) island size, (c) distance to the mainland, (d) crossing distance at low tide, (e) distan... Samuel A. Iverson et al. Proc. R. Soc. B 2014;281:20133128 2014 by The Royal Society