Using a double codend to reduce discard mortality

Broadhurst, M.K., Millar, R.B., Uhlmann, S.S.
Journal/Publisher Name
ICES Journal of Marine Science
Volume (Issue #)
Page #s
Contact information
M.K. Broadhurst and S.S. Uhlman
NSW Department of Primary Industries
Fisheries Conservation Technology Unit
PO Box J321
Coffs Harbor, NSW 2450, Australia

A double codend was compared to the standard codend in the Clarence River penaeid trawl fishery in southeastern Australia, to determine its effects on total catch, retained and discarded school prawns, sizes of discarded prawns, discarded fish and immediate and short-term mortalities of discarded juvenile school prawns.  The only significant difference between gear types was the immediate and short-term discard mortalities, which were reduced by 13.8% and 17.1% respectively when the double codend was used.  Additional analysis also showed that mortalities of school prawns increased with the quantity of jellyfish.