Aller au contenu principal

    Pleuragramma antarcticum distribution in the Ross Sea during late austral summer 2013

    Demander un document de réunion
    Numéro du document:
    WG-EMM-14/38
    Auteur(s):
    C. Brooks and K. Goetz (USA)
    Soumis par:
    Doug Cooper (Secrétariat de la CCAMLR)
    Résumé

    Research during the last decade has revealed much about the early life history of Pleuragramm antarcticum, including confirmation of the first known nursery ground in Terra Nova Bay. However, there is still much unknown about larval fish distribution in the Ross Sea, Antarctica. During a United States National Science Foundation research cruise in the late austral summer 2013, we opportunistically sampled the icthyoplankton community at 17 locations in the western Ross Sea as well as one location in the central Ross Sea and one location in the far south of the eastern Ross Sea (in the Bay of Whales). Larval P. antarcticum made up more than 99% of the icthyoplankton in the western Ross Sea. Most of these fish had hatched during the current season. Length data from these fish obtained over the course of the cruise supports growth rates and hatching times consistent with reported hatching events in Terra Nova Bay. The most numerous abundances (3400+ in each tow) of larval P. antarcticum were found along the ice margin in the western Ross Sea, further suggesting the importance of sea ice to this species. Finally, a unique tow in the Bay of Whales revealed recently hatched P. antarcticum in mid-March, suggesting the presence of a potential eastern Ross Sea nursery ground. This late hatching period may be explained by latitudinal, climatic and oceanographic variations in this region.