Download FAR 2013/48 Acoustic and trawl estimates of orange roughy (Hoplostethus atlanticus) biomass on the southwest Challenger Plateau, June/July 2011

A trawl and acoustic survey of ORH on flat ground on the southwest Challenger Plateau from FV Thomas Harrison in June/July 2011 found roughy concentrated NE of the Pinnacles. Trawl estimates were 19 717 t (CV 31.2%) or 17 899 t (CV 31.9%), depending on inclusion of a shortened tow; significantly higher than a comparable 2010 survey (12 190 t), but lower than a 2009 survey (46 480 t). The acoustic estimate of aggregated roughy was 9481 t (CV 23.8%); 1.57 times the 2010 estimate, but 58% of 2009.