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    Updated status of Notothenia rossii, Gobionotothen gibberifrons and Notothenia coriiceps in inshore sites of the South Shetland Islands: results of a long-term monitoring program (1983–2016) at Potter Cove

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    Numéro du document:
    WG-FSA-16/02
    Auteur(s):
    E. Barrera-Oro, E. Marschoff and D. Ainley
    Soumis par:
    Esteban Barrera-Oro (Argentina)
    Approuvé par:
    Enrique Marschoff (Argentina)
    Résumé

    Trammel net surveys were continued in Potter Cove, South Shetland Islands, Antarctica, to achieve a 33-year record, 1983-2016, to monitor changes in the prevalence of three species of notothenioid fishes: Notothenia rossii, Gobionotothen gibberifrons and N. coriiceps. Inshore results were consistent with those achieved from the most recent offshore bottom trawl research cruises in 2007 and 2012 around the South Shetland Islands: 1) a continuous increase in the abundance of N. rossii; 2) further decline in G. gibberifrons recruitment evidenced by the low proportions of juvenile fish; and 3) a high abundance of N. coriiceps. Results were also consistent with trends in seabirds that feed on juveniles of these species. The three notothenioids have similar ecological habits nearshore, but while in offshore waters N. coriiceps was never commercially fished, N. rossii and G. gibberifrons were severely impacted by industrial fishing during the late 1970s-onset of the 1980s. Reasons for lack of recovery in G. gibberifrons remain obscure but seemingly relate to the dramatically changing ecosystem of the region due to climate and perhaps recovery of previously depleted upper trophic level species. Under the regulation of CCAMLR, commercial fishing for finfish in the South Shetland Islands region (FAO Subarea 48.1) remains prohibited since 1991; results indicate that it cannot be reinstated.