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The Murray Cod is Australia's
best known and most sought after freshwater fish. It can
grow to weights of up to 45kg, although fish of this size
are rare today.
The Murray Cod is big, robust
and barrel shaped with a huge mouth and small eyes set well
forward on the head. It is not a particularly good fighting
fish, in fact is is quite lazy. It is olive green to
yellow/green or grey/green on the back fading to yellowish
on the flanks and creamy yellow or white on the belly. The
back is overlaid with darker green or brown mottling and
reticulations which often extend well down the flanks. The
eyes are brown.
The second dorsal and caudal
fins usually have white margins and sometimes such margin is
also found on the ventral fin. These fin tip colours are
particularly striking on fish from clearer, faster flowing
streams.
The Murray Cod is found in
the entire Murray/Darling river systems, with the exception
of the alpine and sub-alpine headwaters. Cod have also been
introduced into many dams and some eastern flowing (coastal)
drainage's. They are found in habitats ranging from
shallow, fast-running streams with gravel beds to deep,
turbid and slow flowing western rivers. They also thrive in
dams. Even in quick flowing streams, Murray Cod tend to be
found in deep holes, slicks and back eddies. They favour
deep water, cover and a ready access to food.
Murray cod grow rapidly in the first 4-5 years and are usually sexually mature at 4 years of age. Some individual fish can reach 64cm in the fifth year. Fully grown Murray cod have been known to attain 1.8 metres in length and weigh up to 113.5kg.
Murray cod are carnivorous, taking a wide variety of food from molluscs and
crustaceans to many species of fish and occasionally water birds such as duck.
Spawning occurs in the spring and summer months in water temperatures between 16 and 21oc. Females can lay up to 40,000 eggs which are deposited in hollow logs or shallow water. Eggs hatch 6 to 13 days later, with juvenile fish feeding freely about 3-4 weeks later.
Murray cod are produced in hatcheries, enabling enhancement of
existing population, or restoration of the species to waters considered suitable for survival and growth of released fish. Its husbandry is well known and the species lends itself to polyculture
e.g. catfish. There is one hatchery in central Victoria producing weaned fingerlings at 8 to 10 weeks of age from 0.5 to 1 gram, reared in plankton ponds. Cost fluctuates depending on volume purchased and other factors from 25c to 90c each.
Murray cod readily adapt to artificial environments and pelletised feeds. Australian Culture Eels at Euroa in Central Victoria are using a state-of-the-art closed system developed in Europe to grow out Murray cod. The company has been established less than two years and is set up to grow out Murray cod, silver perch, catfish and short finned eels. Other Murray cod farming ventures are being established by traditional land farmers who look to diversify into new export focused production opportunities.
Murray cod in the wild are extremely territorial and will kill others coming into its area. High density stocking of the fish tends to suppress this instinct and avoid injury to stock. High stocking densities have been achieved in intensive systems of up to 100kg/m3. However average stocking density for grow out is currently 45-50 kg/m3. Target size is 500-600 grams which is plate size. This can be achieved in 9-12 months, or fish can be held for specialty Chinese banquet markets and grown to 1.5kg.
Grown in ponds or tank systems, with optimum water temperature 24-25o C in Gippsland. Limited large water in open ponds exist so most growout facilities are reticulated tank systems. Water needs to be medium to high quality.
As for Barramundi, the capital cost of establishing a closed system Murray cod farm producing about 120 tonnes of product per year is in the order of $2 million. The annual operating costs are estimated to be $0.3 -0.4 million.
There is a commercial wild harvest fishery for Murray cod in NSW and SA. Production from these fisheries is highly variable and restrict to a minimum size of 2.5kg size fish. This is sold gilled and gutted at - $18-25 kg, with prices in excess of $30 kg for live product being achieved to date.
No Information available at this time
Applicants for a new aquaculture licence should read through the following information. Licence application forms can be obtained from the
Fisheries Victoria Aquaculture Unit head office or from regional NRE offices.
Murray Cod has been listed under the
Flora and Fauna Guarantee Act 1988. Under this legislation, the taking, possession or trading of Murray Cod is prohibited without a permit, license or Governor-in-Council Order issued under the Act.
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Source:
http://www.nre.vic.gov.au/
An established commercial hatchery is operated by Brendan Larkin at Euroa, Victoria.
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Source:
http://www.aaq.com.au/
No Information available at this time
No Information available at this time
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