Evidence for density dependent population regulation in southern elephant seals in the southern Indian Ocean
The means by which populations are regulated form a central theme in conservation biology, and much debate has revolved around density dependence as a mechanism driving population change. Marion Island (46o54'S, 37o45'E) is host to a relatively small breeding population of southern elephan...
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Zoological Society of Southern Africa
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ftunivpretoria:oai:repository.up.ac.za:2263/9032 2023-05-15T16:05:12+02:00 Evidence for density dependent population regulation in southern elephant seals in the southern Indian Ocean Pistorius, Pierre Anton Taylor, F.E. Bester, Marthan Nieuwoudt Hofmeyr, G.J. Greg (Gordon John Gregory) Kirkman, Steve P. (Stephen Patrick) 2008-04 http://hdl.handle.net/2263/9032 en eng Zoological Society of Southern Africa http://hdl.handle.net/2263/9032 Pistorius, PA, Taylor, FE, Bester, MN, Hofmeyr, GJG & Kirkman, SP 2008, 'Evidence for density dependent population regulation in southern elephant seals in the southern Indian Ocean', African Zoology, vol. 43, no. 1, pp. 75-80. [http://www.journals.co.za/ej/ejour_afzoo.html] 1562-7020 Zoological Society of Southern Africa Population regulation Southern elephant seal -- Reproduction Southern elephant seal -- Marion Island Allee effect Article 2008 ftunivpretoria 2022-05-31T13:19:56Z The means by which populations are regulated form a central theme in conservation biology, and much debate has revolved around density dependence as a mechanism driving population change. Marion Island (46o54'S, 37o45'E) is host to a relatively small breeding population of southern elephant seals, which like its counterparts in the southern Indian and southern Pacific Oceans, have declined precipitously over the past few decades. An intensive mark-recapture study, which commenced in 1983, has yielded a long time-series of resight data on this population. We used the program MARK to estimate adult female survival in this population from resight data collected over the period 1986-1999. Including concurrent population counts as covariates significantly improved our mark-recapture models and suggests density dependent population regulation to be operational in the population. Although predation may have been involved, it is far more likely that density dependent regulation has been based on a limited food supply. A significant increase in adult female survival was evident which is likely to have given rise to recent changes in population growth. Article in Journal/Newspaper Elephant Seal Elephant Seals Marion Island Southern Elephant Seal Southern Elephant Seals University of Pretoria: UPSpace Indian Pacific |
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Open Polar |
collection |
University of Pretoria: UPSpace |
op_collection_id |
ftunivpretoria |
language |
English |
topic |
Population regulation Southern elephant seal -- Reproduction Southern elephant seal -- Marion Island Allee effect |
spellingShingle |
Population regulation Southern elephant seal -- Reproduction Southern elephant seal -- Marion Island Allee effect Pistorius, Pierre Anton Taylor, F.E. Bester, Marthan Nieuwoudt Hofmeyr, G.J. Greg (Gordon John Gregory) Kirkman, Steve P. (Stephen Patrick) Evidence for density dependent population regulation in southern elephant seals in the southern Indian Ocean |
topic_facet |
Population regulation Southern elephant seal -- Reproduction Southern elephant seal -- Marion Island Allee effect |
description |
The means by which populations are regulated form a central theme in conservation biology, and much debate has revolved around density dependence as a mechanism driving population change. Marion Island (46o54'S, 37o45'E) is host to a relatively small breeding population of southern elephant seals, which like its counterparts in the southern Indian and southern Pacific Oceans, have declined precipitously over the past few decades. An intensive mark-recapture study, which commenced in 1983, has yielded a long time-series of resight data on this population. We used the program MARK to estimate adult female survival in this population from resight data collected over the period 1986-1999. Including concurrent population counts as covariates significantly improved our mark-recapture models and suggests density dependent population regulation to be operational in the population. Although predation may have been involved, it is far more likely that density dependent regulation has been based on a limited food supply. A significant increase in adult female survival was evident which is likely to have given rise to recent changes in population growth. |
format |
Article in Journal/Newspaper |
author |
Pistorius, Pierre Anton Taylor, F.E. Bester, Marthan Nieuwoudt Hofmeyr, G.J. Greg (Gordon John Gregory) Kirkman, Steve P. (Stephen Patrick) |
author_facet |
Pistorius, Pierre Anton Taylor, F.E. Bester, Marthan Nieuwoudt Hofmeyr, G.J. Greg (Gordon John Gregory) Kirkman, Steve P. (Stephen Patrick) |
author_sort |
Pistorius, Pierre Anton |
title |
Evidence for density dependent population regulation in southern elephant seals in the southern Indian Ocean |
title_short |
Evidence for density dependent population regulation in southern elephant seals in the southern Indian Ocean |
title_full |
Evidence for density dependent population regulation in southern elephant seals in the southern Indian Ocean |
title_fullStr |
Evidence for density dependent population regulation in southern elephant seals in the southern Indian Ocean |
title_full_unstemmed |
Evidence for density dependent population regulation in southern elephant seals in the southern Indian Ocean |
title_sort |
evidence for density dependent population regulation in southern elephant seals in the southern indian ocean |
publisher |
Zoological Society of Southern Africa |
publishDate |
2008 |
url |
http://hdl.handle.net/2263/9032 |
geographic |
Indian Pacific |
geographic_facet |
Indian Pacific |
genre |
Elephant Seal Elephant Seals Marion Island Southern Elephant Seal Southern Elephant Seals |
genre_facet |
Elephant Seal Elephant Seals Marion Island Southern Elephant Seal Southern Elephant Seals |
op_relation |
http://hdl.handle.net/2263/9032 Pistorius, PA, Taylor, FE, Bester, MN, Hofmeyr, GJG & Kirkman, SP 2008, 'Evidence for density dependent population regulation in southern elephant seals in the southern Indian Ocean', African Zoology, vol. 43, no. 1, pp. 75-80. [http://www.journals.co.za/ej/ejour_afzoo.html] 1562-7020 |
op_rights |
Zoological Society of Southern Africa |
_version_ |
1766401090792718336 |