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Adult reproductive data for redbait is based on collections taken by midwater trawling during the spawning season and includes the biological information - size, sex, reproductive condition (weight and stage). Histological examination of mature ovaries provides information on spawing activity and preserved gonads are examined to determine batch fecundity.
Database contains information on eggs and larvae of redbait (Emmelichthys nitidus) collected during surveys conducted around eastern to south-western Tasmania in October 2005 and 2006. The database also contains details of each sampled station (e.g. depth, Lat, Long, sampling time) as well as information on the volume of water sampled by each net which is needed to estimate relative abundance of eggs and larvae (numbers per metre square). A separate database contains all data of physical variables recorded by depth simultaneously with each sample, including temperature and salinity.
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.