Trends in the breeding population of Adelie penguins in the
Details of Research
TitleTrends in the breeding population of Adelie penguins in the Ross Sea, 1981-2012: A coincidence of climate and resource extraction effectsAbstractMeasurements of the size of Adelie penguin (Pygoscelis adeliae) colonies of the southern Ross Sea are among the longest biologic time series in the Antarctic. We present an assessment of recent annual variation and trends in abundance and growth rates of these colonies, adding to the published record not updated for more than two decades. High angle oblique aerial photographic surveys of colonies were acquired and penguins counted for the breeding seasons 1981-2012. In the last four years the numbers of Adélie penguins in the Ross and Beaufort Island colonies (southern Ross Sea metapopulation) reached their highest levels since aerial counts began in 1981. Results indicated that 855,625 pairs of Adélie penguins established breeding territories in the western Ross Sea, with just over a quarter (28 of those in the southern portion, constituting a semi-isolated metapopulation (three colonies on Ross Island, one on nearby Beaufort Island). The southern population had a negative per capita growth rate of -0.019 during 1981-2000, followed by a positive per capita growth rate of 0.067 for 2001-2012. Colony growth rates for this metapopulation showed striking synchrony through time, indicating that large-scale factors influenced their annual growth. In contrast to the increased colony sizes in the southern population, the patterns of change among colonies of the northern Ross Sea were difficult to characterize. Trends were similar to southern colonies until the mid-1990s, after which the signal was lost owing to significantly reduced frequency of surveys. Both climate factors and recovery of whale populations likely played roles in the trends among southern colonies until 2000, after which depletion of another trophic competitor, the Antarctic toothfish (Dissostichus mawsoni), may explain the sharp increasing trend evident since then. © 2014 Lyver et al.AcknowledgementsLogistics were provided by Antarctica New Zealand, with support from the New Zealand Defense Force, and the US Antarctic Program. We thank the members of the New Zealand Antarctic Fisheries Working Group, in particular Ben Sharp and Matt Pinkerton, Cissy Pan, Christine Bezar and the two anonymous reviewers for their reviews and contributions to this paper.Funding DetailsOPP 0944411, NSF, National Science Foundation
Details
1st AuthorLyver, P.AuthorLyver, P.Barron, M.Barton, K.Ainley, D.Pollard, A.Gordon, S.McNeill, S.Ballard, G.Wilson, P.Year2014JournalPLoS ONEVolume9Number3DOI10.1371/journal.pone.0091188URLhttps://www.scopus.com/inward/recor.....ed667162a48382b1f4df93ea0KeywordsAntarcticaarticlebreedingclimatecompetitor speciesDissostichus mawsonifishgeographic distributiongrowth ratemetapopulationnonhumanorganism colonypenguinphotographypopulation abundancepopulation growthPygoscelis adeliaetrend studyanimalbaypopulation densitytime, AnimalsAntarctic RegionsBaysBreedingClimatePopulation DensitySpheniscidaeTime Factors, rank5
Other
TypeArticleCitationLyver, P., Barron, M., Barton, K., Ainley, D., Pollard, A., Gordon, S., McNeill, S., Ballard, G. and Wilson, P. (2014). Trends in the breeding population of Adelie penguins in the Ross Sea, 1981-2012: A coincidence of climate and resource extraction effects. PLoS ONE, 9(3) IdentifierLyver2014Relevancerank5
Wilson, P., Trends in the breeding population of Adelie penguins in the , [Lyver2014]. Antarctica NZ, accessed 02/10/2023, https://adam.antarcticanz.govt.nz/nodes/view/63625, 10.1371/journal.pone.0091188