Population dynamics of southern elephant seals : a synthesis of three decades of demographic research at Marion Island

Southern elephant seal Mirounga leonine numbers declined precipitously throughout most of their circumpolar distribution since the 1950s. A long-term intensive demographic programme was initiated in 1983 on the relatively small population of southern elephant seals at sub-Antarctic Marion Island in...

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Bibliographic Details
Published in:African Journal of Marine Science
Main Authors: Pistorius, Pierre Anton, De Bruyn, P.J. Nico, Bester, Marthan Nieuwoudt
Format: Article in Journal/Newspaper
Language:English
Published: Taylor & Francis 2011
Subjects:
Online Access:http://hdl.handle.net/2263/19616
https://doi.org/10.2989/1814232X.2011.637357
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Summary:Southern elephant seal Mirounga leonine numbers declined precipitously throughout most of their circumpolar distribution since the 1950s. A long-term intensive demographic programme was initiated in 1983 on the relatively small population of southern elephant seals at sub-Antarctic Marion Island in an attempt to identify causative mechanisms associated with this decline. Weaned pups have been tagged annually since 1983, and this has produced a large number of individuals of known identity. A regular resighting programme yielded a mark-recapture dataset that has been subjected to numerous survival-based models. This ongoing programme produced a substantial body of scientific literature on population growth patterns, vital rates (survival and fecundity) and population regulation in southern elephant seals, which are reviewed in this synthesis. We briefly describe the analytical framework common to much of the demographic research, highlight important conclusions concerning population regulation of elephant seals at Marion Island, and discuss priorities for future research. The Department of Environmental Affairs provided both financial and logistical support for research at Marion Island in earlier years. More recently the Department of Science and Technology provided the funding, managed by the National Research Foundation. http://www.tandfonline.com/loi/tams20