2015-11-10 - P&O Agenda - Item 7, Attach 1 - Historical Ecology of the Noosa Estuary Fisheries

case, a reporting bias exists. The existence and extent of reporting bias was
evaluated by comparing catch rates from different sources: government records,
recreational catch rates reported in newspapers, and fishing competitions (best
and average catch rates). Government records of recreational fish catches exist
for the years 1961-2, when fishery inspectors at Tewantin inspected recreational
fishers’ catches to determine whether undersized fish were being illegally
retained. In so doing, they provided information on the species and number of
fish caught, locations fished, number of people fishing, and in some instances,
number of hours fished. Catch rates from this data set are thus assumed to be
reliable and representative of the size of catches that occurred at this time.


Catch rates between the four sources (recreational records, best competition
catch, average competition catch, government survey records) were compared.
Significant differences occurred between the four datasets (Kruskal-
Wallis=301.6, p=<0.001). Post-hoc tests revealed that average competition
results (1950-1970) showed no significant differences to government survey
data, while records of best competition catch rates were comparable to
recreational records. This information suggests that records of recreational
catches are indeed biased towards the best catch rates, but that reports of
average competition catches are likely to provide a more accurate depiction of
historical catch rates and trends over time.



Early controversy: net versus line

The controversy between net and line fishers is not new. Maintaining the
attraction of Tewantin as a recreational fishing centre was a factor in the
prohibition of net fishing in certain parts of the Noosa River and Lakes from the
early decades of the 20th century (Department of Harbours and Marine 1934). In
1914 net fishing was prohibited in parts of the Noosa River and Lake
Cootharaba, with further limits applied in 1919. From 1925 further portions of
the Noosa River were closed to net fishing (Department of Harbours and Marine
1934). In 1933 a number of commercial fishers formally requested that Weyba
Creek be closed to net fishing for two years, to enable the fish to travel into the


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