Contrasting migratory responses of two closely related seabirds to long-term climate change

Abstract

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 559:231-242 (2016) - DOI: https://doi.org/10.3354/meps11875 Contrasting migratory responses of two closely related seabirds to long-term climate change W. James Grecian1,*, Graeme A. Taylor2, Graeme Loh3, Rona A. R. McGill4, Colin M. Miskelly5, Richard A. Phillips6, David R. Thompson7, Robert W. Furness1 1Institute of Biodiversity, Animal Health & Comparative Medicine, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK 2Department of Conservation, PO Box 10420, Wellington 6143, New Zealand 3Department of Conservation, PO Box 5244, Dunedin 9058, New Zealand 4NERC Life Sciences Mass Spectrometry Facility, Scottish Universities Environmental Research Centre, Rankine Avenue, East Kilbride G75 0QF, UK 5Museum of New Zealand Te Papa Tongarewa, PO Box 467, Wellington 6140, New Zealand 6British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK 7National Institute of Water and Atmospheric Research Ltd, Kilbirnie, Wellington 6021, New Zealand *Corresponding author: james.grecian@glasgow.ac.uk ABSTRACT: Many marine predators migrate between breeding and non-breeding areas to target resources that are seasonal but spatio-temporally predictable, and so are vulnerable to climate-induced changes in prey phenology and abundance. In the Southern Ocean, small petrels are major consumers, but perturbations in the ecosystem through ocean warming are altering food-web structure and have been linked to poleward shifts in the distribution of their cold-water zooplankton prey. In this study, we focused on 2 small congeneric petrels: the broad-billed prion Pachyptila vittata and the Antarctic prion P. desolata. Both are planktivorous, but the broad-billed prion specialises in feeding on large copepods. We investigated historical trends in non-breeding distribution by analysing feather stable isotope ratios from a time-series dating back to 1926, and examined contemporary non-breeding distributions of broad-billed prions tracked using miniaturised geolocation-immersion loggers. After controlling temporally for the Suess effect, we found that the δ13C signatures of Antarctic prions, but not broad-billed prions, declined during the study period. This suggests a southward shift in Antarctic prion non-breeding distribution over the last century. Both species exhibited significant declines in δ15N during the same period, indicative of long-term decreases in marine productivity in their moulting areas, or changes in the trophic structure of prey communities. Tracked broad-billed prions migrated ca. 1000 km to an area east of the breeding colony where the Louisville seamount chain bisects the subtropical front. Topographically driven upwellings are stable and predictable features and may be crucial in aggregating plankton. Targeting seamounts could therefore mitigate the impact of climate-induced prey shifts by providing refugia for the broad-billed prion. KEY WORDS: Biologging · Conservation · Migration · Moult · Movement · Non-breeding behaviour · Seamounts · Stable isotopes · Upwelling zones Full text in pdf format PreviousNextCite this article as: Grecian WJ, Taylor GA, Loh G, McGill RAR and others (2016) Contrasting migratory responses of two closely related seabirds to long-term climate change. Mar Ecol Prog Ser 559:231-242. https://doi.org/10.3354/meps11875 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 559. Online publication date: November 09, 2016 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2016 Inter-Research.