We review our experiences on biology, stock differentiation and commercial potential of snappers in three study areas: i. an Etelis carbunculus fishery off the west coast of Australia; ii. shared snapper stocks (Lutjanus malabaricus, L. erythropterusand Pristipomoides multidens] between Indonesia and Australia and iii. Etelis, Pristipomoides and Lutjanus spp. off Lihir Island, Papua New Guinea. In some cases, we collected critical population dynamics information in order to undertake stock assessments. Even so, the information base for stock assessment was often weak. For example, ageing of these tropical species is difficult commercially, artisanal data in some regions are incomplete and juvenile animals were under-represented as their nursery grounds were difficult to identify. Although the general life-history parameters known for these species were found to be applicable, key population dynamic parameters described for the same species from elsewhere in the tropics were not transferable to thestudy areas. Growth rates and reproductive activity show significant regional variation. Further, the deep trenches between the Indonesian islands increase the potential for stock differentiation. Some of these species are unproductive. Based on these findings, the stock assessments confirmed that many of these fisheries are not able to maintain medium to large-scale fisheries and need to be carefully managed.
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