Injury, physiological stress and mortality of recreationally discarded crustaceans in New South Wales, Australia

Australian recreational fishers discard large amounts of decapod crustaceans each year, but no formal studies have investigated their fate. To assess this, Scylla serrata, Portunus pelagicus and Sagmariasus verreauxi were trapped in New South Wales using popular recreational trap designs, before subsequent assessment of injury, physiological stress and mortality were made. For all species, physiological changes were generally transitory and capture-related injury was mostly non-lethal. Some S. verreauxi died (3.3%) from within-trap predation and minimal trapping-related P. pelagicus mortality occurred (1.1%). No S. serrata died. The results support the use of mandatory discarding to help control stock exploitation.