Port Phillip Bay and Bass Strait scallop research
Final report
During the 3 years of the study, scallop spatfall was observed to occur over a short period (October-December) after the scallops had spawned in spring. Growth was rapid and scallops reached an acceptable harvestable size of 70mm within 16 months. Spatfall one year can therefore be related to recruitment during the next. Years of high and low spatfall were reflected in subsequent differences in recruitment. Though more years' data are required, indices of spatfall provide managers and fishermen with predictive information on likely recruitment strength one year in advance.
Each year the strength of recruitment and the residual stock size were estimated from the results of surveys by SCUBA divers. The results have shown that commercial viability of the fishery is primarily dependent upon recruitment each year. Residual stocks are normally insufficient to support the fishery in the event of poor recruitment.
Estimates of growth and mortality rates determined from tagging and data on seasonal changes in meat yield have been used to develop a mathematical model which can be used to determine number of scallops available each season and yields obtainable from different management strategies. Estimates from annual survey, of stock abundance and mean scallop size at the beginning of each year provide the data for the model.
As a result of the research program, the need to continue monitoring spatfall in Port Phillip Bay and to conduct surveys of recruitment strength each year has been identified. These data are necessary for fisheries managers to maintain the ability to manage the stocks by quota system.
Ensuring market-focused value adding capabilities are available to SA Seafood companies today and through to 2030
Tactical Research Fund: Establish the acceptability of the Queensland Endeavour prawn as a product of choice in the Qld domestic market
The Endeavour prawn has traditionally been successfully marketed into the European Union but over the last few years a number of factors have forced this product from that market.
The two principal factors are:
1. The EU now tests extensively for cadmium levels in prawn and unfortunately on an irregular basis the level in Endeavour prawn exceeds the EU standard. Shipments have been rejected by Customs in the EU even
after testing in Australia has shown the product to be at acceptable levels.
2. Catches of Argentinian prawn have increased substantially over the last few years and due to their high quality and low price have become the prawn of choice for the EU.
This has created a situation in Australia where product being harvested in the Gulf of Carpenteria, Torres Strait and Queensland East Coast has become virtually unsaleable.
However, while work continues to be undertaken to resolve issues on Cadmium levels it is important that catchers look to diversify market opportunities, targeting and maximizing previously smaller local markets.
With catches from these areas exceeding 1,000tonnes each year it is imperative that alternative options be developed to maximize the economic yield of this catch.. Failure to do so will unquestionably accelerate the the parlous state of the Qld trawl industry. We believe that there exists a good opportunity to address this situation via sensible planning and marketing of this product.