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When BY JOHN MOSIG Ready for market! A sample of cod from Thurla Farms does a cod HAVE TWO TALES? Col Beasley proudly shows off some of the cod produced in Thurla Farms' floating raceway system W hen does a cod have two tales? When it's part of an aquaculture development scheme. Over recent years Fisheries Victoria, with the enthu- siastic support of Col Beasley of Thurla Farms, a prominent farmer in Victoria's Sunraysia Irrigation District, has been driv- ing a development programme for Murray cod (Maccullochella peelii peelii) with funding from the Australian Department of Primary Industry. While some success has been achieved, the programme has stirred up considerable controversy. Sunraysia is a major horticulture region and many farms have holding reservoirs of over 2ha. The idea was to use this water storage to grow the iconic Murray cod in fl oating raceways. The fl oating fi sh farm module consisted of four 15m x 2m x 2m fl oating raceways complete with walkways, a fi sh treat- ment bay, anti-bird netting, automatic feeders and an aeration system. Col Beasley says under ideal conditions, each module can produce 40 tonnes of cod over 18 months, spanning two growing seasons. Fisheries' have worked for several years doing on-site trials, developing a marketing plan under the Murray Gold brand. They are also seeking funding for veterinarian expertise and advice. Col predicts Murray cod has a promising future in the region. "The double use of water to produce a high-value crop such as Murray cod has a lot to commend it." The fi sh are grown in two stages. During the hatchery/ nursery stage, the cod are spawned and the larvae taken from fry to 100g fi ngerlings over their fi rst winter in temperature- controlled re-circulation units. Although Sunraysia, as the name implies, receives abundant sunshine and hot summers, it has a continental climate. During winter, overnight temperatures can fall below zero and water temperatures fall to 9˚ Celsius for 10 to 12 weeks. The six-month growing season in the fl oating runs from October to March. Once the water temperatures reach 18˚ Celsius they stock the 100g fi ngerlings. The cod are graded regularly to remove shooters and prevent cannibalism and are graded again toward the end of their fi rst season. At this stage most of the cod weigh around 500g, with extremes of 200g to 750g. 8 ■ NZ AQUACULTURE ■ NOVEMBER/DECEMBER 2011 During the second growing season they are harvested as they reach the market size of 800g to 1.4 kilos. The cod need constant monitoring for health issues. While this may seem labour-intensive, the cages are designed so it only takes two minutes to move the fi sh into the central treatment tank, says Col. "We don't have to handle the fi sh or remove them from the water." However, not everyone who went into the programme is as enthusiastic as Col. Four years ago Barry Avery, a table and wine grape and avocado grower, was attracted to aquaculture after reading a DPI report on the viability of farming Murray cod in Sunraysia. "I invested quite heavily in a fl oating module recommended by the DPI. I thought I'd followed up the markets but all the information I'd been given on marketing, the time required to manage the operation, feed conversion and stocking densi- ties and mortalities seemed to be heavily infl uenced by the desired outcomes, rather than the harsh realities of commercial aquaculture. They turned out to be impractical in a real-life situation", Barry said. "Lack of support was probably the single key item missing from the scheme. The DPI people were enthusiastic about the project at the fi eld days, but when it came to practical support and training, there was nothing there. "I should have heard the alarm bells from the fi nal report when it concluded: "Key risks and opportunities include best practice guidelines, integration and coordination of the value chain, elite strains of fi nfi sh for aquaculture, water quality issues, industry education and training and export development". However, this was prefaced by the statement that, "Open water farming of Murray cod in private irrigation storage dams in northwestern Victoria is now at a 'commercial-ready' stage and is potentially a new A$50 million industry for Victoria. "In hindsight, you would be excused for thinking the risks were for the investors and the opportunities were for the DPI people running the project." The jury is still out on the future of the programme. Murray cod grown in fl oating raceways is reaching the market from Sunraysia. However, at this point it's not clear if they are being sold for a profi t.