Starting in the mid 1980s, Australia has experienced an increased public
awareness of harmful algal blooms, especially their suspected involvement
in causing fish kills and feared public health risks following consumption
of contaminated seafood products and drinking water supplies. If not
adequately monitored and managed, the economic impacts on Australia's
developing aquaculture industry and on both domestic and export markets
could be devastating. An example of the first problem is the 1989 bloom
event by the golden-brown flagellate Heterosigma akashiwo in Big Glory
Bay, New Zealand, which killed NZ$ 12 million worth of cage-reared chinook
salmon. An example of the second problem is the 1993 New Zealand outbreak
of neurotoxic shellfish poisoning by the dinoflagellate Gymnodinium cf.
breve (NSP; 180 illnesses, no deaths) which led to export losses of NZ $
4.5 million in the first quarter of 1993 and a 25% decrease in domestic
shellfish demand . Similarly, positive test results are now available from
Australian shellfish products for paralytic shellfish poisons (NSW,
TAS,VIC,SA), diarrhetic shellfish poisons (TAS), amnesic shellfish poisons
(VIC) , neurotoxic shellfish poisons (VIC) and cyanobacterial peptide
toxins (WA). While algal biotoxins only in extreme cases lead to human
fatalities, it is the so-called "halo"-effect of bad publicity resulting
from a few human poisonings that can devastate aquaculture industries.
Compared to our neighbour New Zealand, which spends $3.2 M per year in
biotoxin monitoring efforts (most comes from the Ministry of Health, with
industry providing $750,000 per year via an industry levy), Australian
efforts in this area of quality assurance and environmental protection of
aquaculture operations are unsatisfactory.

Through existing farming practices it is apparent that there are several factors which may be limiting production and ultimately revenue.

Firstly, there is a need to identify an “ideal production strategy” to achieve forecast production levels. As temperature significantly affects YTK growth, feed conversion ratios and health, it is essential that the relationship between growth and temperature is investigated in fish of various sizes. This information will enable CST to make informed decisions on size and time of stocking YTK into sea cages. It is anticipated that this will improve production through shortening the production cycle and will reduce the standing biomass in the water, ultimately increasing farm profitability.

Secondly, maturation may be a constraining factor in YTK production, reducing somatic growth. There are also flesh quality concerns which threaten sales of YTK harvested in November-December, a period when males exhibit maturation. However preliminary analysis of work carried out in Seafood CRC project 2008/901 suggests that male maturity did not have a significant deleterious effect on the flesh quality at that time. Though there are numerous strategies to manage maturation it is initially necessary to characterise the occurrence of maturation and the factors controlling it. With this information, appropriate mitigation strategies can be introduced resulting in economic benefits to the YTK industry.

Lastly, as production is poised to increase, it is imperative that substantial markets are developed for YTK product. One way of increasing sales is to ensure product sold is consistently of the highest possible quality. By attaining knowledge on the quality attributes, shelf-life and nutritional content of the product, producers will be able to tailor a product to specific market requirements. Likewise, as processing techniques and cold chain supply routes are diverse, it is imperative that information is attained on how these influence the quality of the product.