Biology and population dynamics of redbait and jack mackerel

Sampling of commercial mid-water trawl catches for small pelagics from waters adjacent to Tasmania have yielded an extensive biological dataset in space and time. As a minimum, size composition information is available from most commerical shots undertaken between 2002 and 2006, referenced with operational information (location, depth and catch weight). Subsamples of the key small pelagics, redbait, jack mackerel and blue mackerel, were examined for size, sex, gonad weight and stage and otoliths have been retained for age determination. Further data has been collected since the initial investigation.