Potential VMEs around Elephant and the South Shetland Islands (Subarea 48.1)

Bottom trawl sample data from two research cruises were used to identify potential VMEs in the South Shetland Islands area.  High biomass densities of VME indicator taxa, meeting the 10 kg/1200 m² threshold previously set (Lockhart & Jones, 2009), were detected for 5 stations around Elephant Island.  However, this threshold is severely biased towards ‘heavy’ taxa (namely sponges and ascidians) such that communities of many ‘light’ VME taxa have little to no chance of meeting this criterion and are thus not adequately protected unless direct photographic evidence is available.  To this end a new ‘diversity threshold’ is proposed in order to protect those VME taxa that do not occur in the types of communities where sponges and other heavy taxa occur.  A clear example can be made of CITES Appendix II listed Antipatharia (black coral), which in the authors’ experience has never occurred at a high biomass-density station and even large colonies of which weigh relatively little.  After applying the new diversity threshold, a total of 10 VME areas are proposed, half of which encompass multiple stations.