Aller au contenu principal

    BEACH DEBRIS SURVEYS SOUTH SANDWICH ISLANDS

    Demander un document de réunion
    Numéro du document:
    CCAMLR-XVI/BG/10
    Auteur(s):
    Delegation of the United Kingdom
    Point(s) de l'ordre du jour
    Résumé

    Beach debris surveys were carried out at two sites in the South Sandwich Islands (CCAMLR sub-area 48.4) during the 1996/7 austral summer. Two surveys of a north-east facing beach (1 km length) at Demon Point, Candlemas Island were made, separated by exactly one month, in January and February 1997. A single opportunistic survey of a west-facing beach (c. 200 m length) at Ollivant Point, Saunders Island, was made in late January 1997. Incidental observations were n1ade on several other islands in the group.

    Only 8 items were found in the initial survey of Demon Point, Candlemas Island. However, during the subsequent month, 26 further items of debris were washed onto the beach. This rate of deposition is similar to, but at the lower end of, the range reported from beaches on Signy Island, South Orkney Islands during the years 1991-1996. At Ollivant Point 57 items of debris were found, the majority (70%) being pieces of driftwood which had probably been in situ for at least several years. Many smaller types of debris are likely to have a short residence time on any beach in the South Sandwich Islands, due to their great exposure and instability, and the uniformly heavy, often stormy, swell.

    The majority of the items recovered on Demon Point, Candlemas Island, were plastic or polystyrene (6 out of 8 items or 75% of initial survey, 23 out of 26 items or 88% of second survey). Of the 29 such items, 12 were plastic bottles or containers and 16 were whole or fragmented fishing net floats (incidental observations indicated that net floats were present on many beaches in the archipelago). No fragments of net or synthetic fishing line, or packaging bands, were noted on any beach visited in the archipelago. A single entangled female fur seal was freed from a fishing net on Candlemas Island, but no other instances of entanglement or injury to fauna were noted.

    It was possible to identify the country of origin or manufacture of a small proportion of the debris. Attibutable items originated from Argentina and Japan (2 each), Chile and Russia (1 each).

    Despite the extremely remote location of the South Sandwich Islands, these results show that the quantity and rate of deposition of marine debris on the islands' beaches is significant, but low when compared to rates found at Signy Island, South Orkney Islands and Bird Island, South Georgia. However, because of the exposure of beaches in the South Sandwich Islands to heavy and often stormy swell, debris washed ashore is likely to to have only a short residence time before being washed back to sea.

    The total absence of nylon line fragments or packing bands is significant given their high frequency of occurrence at Bird Island and Signy Island respectively. This both confirms there is little or no fishing activity around the South Sandwich Islands at present and suggests that these types of fishery debris are not carried to the archipelago from active fisheries around South Georgia and the South Orkney Islands.