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.
This is a preview of subscription content, log in via an institution to check access.
References
Bester MN (1980) Population increase in the Amsterdam Island fur seal Arctocephalus tropicalis at Gough Island. S Afr J Zool 15:229–234
Bester MN (1982a) Distribution, habitat selection and colony types of the Amsterdam Island fur seal Arctocephalus tropicalis at Gough Island. J Zool Lond 196:17–231
Bester MN (1982b) The effect of the Subantarctic environment on aspects of the terrestrial phase of fur seal populations. Com Nat fr Rech Antarct 51:469–478
Bester MN (1984) Status of the populations of the fur seals Arctocephalus tropicalis and Arctocephalus gazella north of the Antarctic Convergence. S Afr J Sci 80:27–28
Bester MN (1987) Subantarctic Fur Seal, Arctocephalus tropicalis, at Gough Island (Tristan da Cunha Group). In: Croxall JP, Gentry RL (eds) Status, biology, and ecology of fur seals: proceedings of an international symposium and workshop, Cambridge, England, 23–27 April 1984, NOAA Technical Report NMFS 51, Seattle, Washington, pp 57–60
Bester MN (1990) Population trends of Subantarctic fur seals and southern elephant seals at Gough Island. S Afr J Antarct Res 20:9–12
Bester MN, Ryan PG (2007) Mammals. In: Ryan P (ed) Field guide to the animals and plants of Tristan da Cunha and Gough Island. Pisces Publications, Newbury, pp 99–108
Bester MN, Ryan PG, Dyer BM (2003) Population numbers of fur seals at Prince Edward Island, Southern Ocean. Afr J mar Sci 25:549–554
Bester MN, Wilson JW, Burle M-H, Hofmeyr GJG (2006) Population trends in Subantarctic fur seals at Gough Island. S Afr J Wildl Res 36:191–194
Bester MN, Ryan PG, Bester WA, Glass T (2014) Vagrant Antarctic fur seals at the Tristan da Cunha Islands. Polar Biol 37:1701–1703
Condy PR (1978) Distribution, abundance and annual cycle of fur seals (Arctocephalus spp.) on the Prince Edward Islands. S Afr J Wildl Res 8:159–168
Cooper J, Headland RK (1991) A history of South African involvement in Antarctica and at the Prince Edward Islands. S Afr J Antarct Res 21:77–91
Hofmeyr GJG, Bester MN, Jonker FC (1997) Changes in population sizes and distribution of fur seals at Marion Island. Polar Biol 17:150–158
Hofmeyr GJG, Bester MN, Makhado AB, Pistorius PA (2006) Population changes in Subantarctic and Antarctic fur seals at Marion Island. S Afr J Wildl Res 36:55–68
Kerley GIH (1983) Relative population sizes and trends, and hybridisation of fur seals Arctocephalus tropicalis and A. gazella at the Prince Edward Islands, Southern Ocean. S Afr J Zool 18:388–392
Lunn NJ, Boyd IL (1991) Pupping-site fidelity of Antarctic fur seals at Bird Island, South Georgia. J Mammal 72:202–206
Wace NM, Holdgate MW (1976) Man and nature in the Tristan da Cunha Islands. IUCN Monogr 6:1–114
Wege M, Etienne M-P, Oosthuizen WC, Reisinger RR, Bester MN, De Bruyn PJN (2016) Trend changes in sympatric Subantarctic and Antarctic fur seal pup populations at Marion Island, Southern Ocean. Mar Mamm Sci 32:960–982
Wilkinson IS, Bester MN (1990) Continued population increase in fur seals, Arctocephalus tropicalis and A. gazella, at the Prince Edward Islands. S Afr J Antarct Res 20:58–63
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.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
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.
Rights and permissions
About this article
Cite this article
Bester, M.N., Wege, M. & Glass, T. Increase of sub-Antarctic fur seals at the Tristan da Cunha Islands. Polar Biol 42, 231–235 (2019). https://doi.org/10.1007/s00300-018-2406-2
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00300-018-2406-2