ANALYSIS OF VME DATA COLLECTED BY UK VESSELS FISHING IN THE ROSS SEA DURING THE 2008/09 CCAMLR SEASON

Analysis of VME data collected in 2008/09 by UK vessels and national and international observers onboard was carried out to explore evidence of VMEs in the Ross Sea. 2008/09 data corroborated areas in 88.1I, E and F identified in our previous analysis of data collected by observers on UK vessels between 2005 and 2007 on benthic taxa recovered from longlines. A new area was identified within 88.1K, not previously detected. A second objective was to determine whether a relationship could be established between VME Indicator Units and CPUE data collected in 2008/09, in order to understand better the meaning of our historical CPUE data. Although a positive (exponential) association was apparent between VME Indicator Units and CPUE (bits/1000 hooks), there were insufficient data at high levels of VME Indicator Units (corresponding with the levels at which notifications to the Secretariat were triggered) to determine a meaningful relationship beyond a suggestion that 5 VME Indicator units was approximately equivalent, on average, to 25 bits/1000 hooks. As expected, heavy large taxa (e.g. gorgonians) triggered 5 VME Indicator Units at lower CPUEs than 25 bits/1000 hooks, and small lighter taxa (e.g. hydrocorals) triggered VME Indicator Units at higher CPUEs. Accounting for different benthic taxa might improve the application of the VME Indicator Units as a means of highlighting potential VME risk areas.