The inland commercial fishery in New South Wales had a mean annual catch of 344t over the past three decades, and is currently worth $1.7 million per annum (1995/96 value). The commercial fishery commenced in the late 19th Century, and although production figures are available from 1883 onwards, coverage for years earlier than 1947 was very limited, with an unknown fraction of the total catch reported. The major species currently exploited by the fishery are golden perch, carp, Murray cod and freshwater yabby, while prior to 1980 redfin perch, silver perch and freshwater catfish were also significant components of the catch.

From the commencement of the commercial fishery there were resource conflicts between commercial fishers, traditional rights of the indigenous fishers, recreational fishers and a continual problem with widespread illegal fishing activities. The geographical extent of the fishery was gradually reduced to the current boundaries, which allow commercial fishing for finfish in approximately 5% of the linear measure of the inland waters of NSW.

There has been a long-established need for reliable data for the fishery, and while fishers have officially reported catches since 1947, the data have been poorly managed, and no comprehensive analysis has previously been attempted.

The present study has identified and corrected a number of errors in the previous datasets. Summaries are given for the catch, effort and catch-per-unit-effort over the period 1947/48 to 1995/96. The catches of golden perch have been relatively stable for the past three decades, with peaks in production following good flood years. Catches of Murray cod declined sharply from a peak in the mid-1950s but have been relatively stable since the mid-1960s, annual catches generally falling within a range of 10-20t. For silver perch and catfish declines have continued to the present situation of a voluntary ban on their capture. Catches of carp stabilised at about 150t after rising rapidly in the 1970s to a peak of 548t.

South Australian catches of golden perch were historically fairly similar to the NSW catches, but since 1992/93 they have increased markedly to approximately three times the NSW catch. Validation of the combined catch data for NSW and South Australia was possible for golden perch, by using data obtained from Melbourne and Sydney Fish Markets. While the information collected from commercial fishers seems to have provided reliable estimates of the total catch and trends in CPUE by species, the data are not adequate for the application of age-based stock assessment techniques. Additional information would have to be collected from fishers and/or from market-based sampling to provide the required information for useful stock assessments. Another important consideration is that even with complete information on the commercial fishery, the geographical extent of the fishery is extremely limited, so that the status of a stock in the commercial fishery may not necessarily reflect the stock status over the whole Murray-Darling system.

While it is possible to collect some summary information on catch and effort relatively easily from the recreational sector, alternative methods would need to be developed to collect the information required for detailed age-based stock assessments from this source. For proper management of the stocks, it is important to have estimates of the catches of the recreational sector, and the long-standing paucity of comprehensive information needs to be remedied.

This study confirms the strong correlation between time series of river levels or flows and catches of Murray cod and golden perch, as suggested in previous studies.

It is recommended

that the paucity of data for the recreational catch of inland species be redressed;

that more detailed, daily records of commercial catches and effort be collected, and a sampling program for lengths/ages and other required biological information be undertaken, particularly for Murray cod and golden perch, in order to ascertain the status of inland fish in the currently fished areas of the Murray-Darling.