Preview

PDF (Published version) 145661 - Climat...pdf | Download (1MB) | Preview

Abstract

The Southern Ocean has been disproportionately affected by climate change and is therefore an ideal place to study the influence of changing environmental conditions on ecosystems. Changes in the demography of predator populations are indicators of broader shifts in food web structure, but long-term data are required to study these effects. Southern elephant seals (Mirounga leonina) from Macquarie Island have consistently decreased in population size while all other major populations across the Southern Ocean have recently stabilized or are increasing. Two long-term mark-recapture studies (1956–1967 and 1993–2009) have monitored this population, which provides an opportunity to investigate demographic performance over a range of climatic conditions. Using a 9-state matrix population model, we estimated climate influences on female survival by incorporating two major climatic indices into our model: The Southern Annular Mode (SAM) and the Southern Oscillation Index (SOI). Our best model included a 1 year lagged effect of SAM and an unlagged SOI as covariates. A positive relationship with SAM1 (lagged) related the previous year's SAM with juvenile survival, potentially due to changes in local prey availability surrounding Macquarie Island. The unlagged SOI had a negative effect on both juvenile and adult seals, indicating that sea ice dynamics and access to foraging grounds on the East Antarctic continental shelf could explain the different contributions of ENSO events on the survival of females in this population.

Item Type:	Article
Authors/Creators:	Volzke, S and McMahon, CR and Hindell, MA and Burton, HR and Wotherspoon, SJ
Keywords:	ecology, demographic modelling, climate influence, southern elephant seal, female survival, Southern Annular Mode, Southern Oscillation Index, capture-mark- recapture studies, demographics, ecological modeling, El Niño Southern Oscillation
Journal or Publication Title:	Ecology and Evolution
Publisher:	John Wiley & Sons Ltd
ISSN:	2045-7758
DOI / ID Number:	10.1002/ece3.7919
Copyright Information:	© 2021 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0) License, (https://creativecommons.org/licenses/by/4.0/) which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Related URLs:	Google Scholar: Volzke, S UTAS Profile: McMahon, CR Google Scholar: Hindell, MA UTAS Profile: Hindell, MA Google Scholar: Wotherspoon, SJ UTAS Profile: Wotherspoon, SJ
Item Statistics:	View statistics for this item

Actions (login required)

Item Control Page