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Polar Biology

, Volume 42, Issue 1, pp 231–235 | Cite as

Increase of sub-Antarctic fur seals at the Tristan da Cunha Islands

  • M. N. BesterEmail author
  • M. Wege
  • T. Glass
Short Note
  • 59 Downloads

Abstract

Sub-Antarctic fur seal, Arctocephalus tropicalis, pups were counted on some of the beaches on all four Tristan da Cunha (TdC) islands, in January 2017, to determine the status of the population, in the face of climate change that is magnified in polar regions. Compared to counts done 40 years earlier on Gough, the breeding population increased markedly on some beaches, although negligibly on the largely open boulder beaches on the leeward northeastern sector of the island. Similarly, on the northern group of the TdC islands, the breeding population had increased markedly (including the very first pup counts at Inaccessible and Nightingale), despite fur seal females currently selecting only certain beaches for pupping (at Inaccessible and Tristan). At Tristan da Cunha, only one small breeding colony occurs which is remote from the human settlement, probably the result of anthropogenic disturbance.

Keywords

Sub-Antarctic fur seals Pup counts Tristan da Cunha islands Population increase 

Notes

Acknowledgements

Andy Schofield from the RSPB arranged for our (MRI, UP) participation in the NGPS expedition to the TdC islands; the NGPS project expedition leader (Paul Rose) and chief scientist (Jennifer Caselle) factored in our research needs; the TdC Conservation and Fisheries departments provided additional logistical support; and the logistical support of the Captain, officers, and crew of the SVS Grenville is acknowledged. The authors thank Dan Meyer (NatGeo) and Jonathan Hall (RSPB) for assistance in the field, and Peter Ryan for sharing his unpublished results from Inaccessible Island.

Compliance with ethical standards

Ethical approval

The University of Pretoria Animal Ethics Committee (Project Number EC077-15) cleared the procedures of this project, executed under an Environmental Research Permit, including the Wildlife and Protected Areas Research Permit, of the Tristan da Cunha Government.

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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Mammal Research Institute, Department of Zoology and EntomologyUniversity of PretoriaHatfield, PretoriaSouth Africa
  2. 2.Tristan da Cunha Conservation DepartmentEdinburghUK

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