Electronic versions

  • Marta Soeffker
    Centre for the Environment, Fisheries and Aquaculture Science, Lowestoft
  • Philip R. Hollyman
    NERC (British Antarctic Survey)
  • Martin A. Collins
    NERC (British Antarctic Survey)
  • Oliver T. Hogg
    Centre for the Environment, Fisheries and Aquaculture Science, Lowestoft
  • Ainsley Riley
  • Vladimir Laptikhovsky
    Centre for the Environment, Fisheries and Aquaculture Science, Lowestoft
  • Timothy Earl
    Centre for the Environment, Fisheries and Aquaculture Science, Lowestoft
  • Jim Roberts
    Anemone, Wellington, NZ
  • Eleanor MacLeod
    Centre for the Environment, Fisheries and Aquaculture Science, Lowestoft
  • Mark Belchier
    NERC (British Antarctic Survey)
  • Chris Darby
    Centre for the Environment, Fisheries and Aquaculture Science, Lowestoft
The South Sandwich Islands (SSI), a chain of volcanic islands in the Atlantic sector of the Southern Ocean, are home to two large notothenoid species: the Patagonian toothfish Dissostichus eleginoides and the Antarctic toothfish Dissostichus mawsoni. Both species support valuable fisheries throughout the Southern Ocean under management of the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR). The SSI region, which is located south of the Southern Antarctic Circumpolar Current Front, has a diverse and distinct biodiversity and it represents a range edge for the distribution of both toothfish species. In this paper we have updated and expanded previous biological analyses with recent data, explored the stock hypotheses and links of these species to other regions, and investigated the role of the SSI archipelago in the life cycles of both toothfish species, where they overlap in their distribution. We conclude that Patagonian toothfish around the SSI are linked to the adjacent South Georgia population, but have some unique characteristics, including faster growth and better somatic condition, possibly reflecting ‘Bergmann's rule’ which states that body size increases with decreasing temperature and increasing latitude. By comparison, the Antarctic toothfish at the SSI appear to be the northern extent of a larger stock connecting further south towards the Antarctic continent. Finally, we consider the relative importance of the SSI in the life cycle of both species, including in the context of climatic changes to this region.

Keywords

  • Antarctic toothfish, Dissostichus spp., Life history, Patagonian toothfish, Range edge distribution, South Sandwich Islands
Original languageEnglish
Article number105098
JournalDeep-Sea Research Part II: Topical Studies in Oceanography
Volume201
Early online date12 May 2022
DOIs
Publication statusPublished - 1 Jul 2022
Externally publishedYes
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