Project number: 1997-206
Project Status:
Budget expenditure: $528,010.19
Principal Investigator: Ian Halliday
Organisation: Department of Agriculture and Fisheries EcoScience Precinct
Project start/end date: 30 Aug 1997 - 25 Mar 2002


There is a critical need for information to support management decisions about inshore fisheries resources, and to address rising industry, conservation and public concern about the impact of net fishing on sustainability and biodiversity of the ecosystem and habitats associated with the fishery. The theory of measuring changes in biodiversity have yet to be applied in net fisheries. This project will be a test case for the practical application of determining net fishing effects on biodiversity.

Information on the effect of net fishing on bycatch and biodiversity in Australia is extremely limited. While some data exist on the marketed catch, the quantity and nature of bycatch remains virtually unknown. There is little information on the total catch characteristics of net fisheries, the proportions of species caught, and the proportion of the resource harvested each year. Similarly little is known about the fate of fish discarded from nets which would help to characterise the impact of net fishing on biodiversity.

This project will address the urgent need for information on the: total catch composition from net fishing, fate of discarded fish bycatch, impact on protected species and impact on biodiversity. Baseline data collected through both fishery dependent and independent methods will provide a basis for long term monitoring of the fishery and will enhance the interpretation of existing commercial catch records. These data will help meet the requirements of the ‘National Strategy for Conservation of Australia’s Biological Biodiversity’ of a) improving the knowledge base of fisheries, b) improving fisheries management and c) assessing and minimising the impact of commercial fishery practices on non-target and bycatch species, ecosystems and genetic diversity.


1. Establish proportions of target catch and bycatch caught in inshore net fisheries along the Queensland east coast and the Gulf of Carpentaria.
2. Characterise the bycatch component of net fisheries in terms of species composition, seasonal abundance, habitat type and mesh size.
3. Determine the fate of fish discarded from net catches.
4. Establish the effects of net fishing on biodiversity through intensive comparative studies of areas closed and open to commercial net fishing.
5. Provide management advice on possible sustainability and biodiversity indicators, and on changes in net fishing practices needed to reduce impacts on bycatch species and biodiversity.

Final report

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