Above an excellent aquacultured jade perch.
Ausyfish can supply fry and fingerlings of Jade Perch, Scortum Barcoo. Click for prices.
This fish originates from the Barcoo River in Central Australia. Ausyfish regularly collects wild fish under permit to use in a genetic improvement program. There are a number of "Scortum" species in Australia, however it has become apparent that only the one from the Barcoo River is suitable for the table. Other river systems have fish that look the same, (See picture below of a Scortum hillii from the Fitzroy/Dawson River Basin.) but are described by local people as "The Leathery Grunter."
Above a Scortum hillii, not considered suitable for the table. Only fingerlings produced from stock originating from the Barcoo River should be used for aquaculture purposes.
AUSYFISH... Australia's largest producer of jade perch fry and fingerlings. We ship to all mainland states of Australia, and export to almost anywhere. AQIS approved. Government health certified. Click for more
Ausyfish is arguably the largest producer of these fish. Jade Perch is a new species to the developing freshwater fin-fish grow-out sector. Over the last few years this species has been tried by a few people in recirculating systems, and a hand full of pond farmers. These pioneering growers found the Jade Perch growing qualities to be excellent. These early results attracted the attentions of some of Queensland's larger growers who have now tried these fish in their large ponds with some great results. Jade Perch really seem to grow very fast compared to Silver Perch. Some growers have even said, twice as fast.
Ausyfish export hundreds of thousands of jade perch fry each season.
Jade Perch don't handle the colder months, or month for Queensland. The feeding behavior of Jade Perch is normally vigorous in the extreme. The fish race towards the end of the pond where the approaching farmer is about to feed, creating quite a bow wave as they begin to break the surface with their heads.
Once they reach the edge of the pond they will extend their entire head from the water in anticipation of a feed. This behavior decreases in intensity as the temperature drops. We are told by growers, that under 18c surface feeding will almost stop. Some farmers have experienced stock losses during winter. On our farm we were able to harvest fingerlings in water temperatures around 14-15c without losses. The difficulties experienced during winter by these early growers have been overcome through management practices.
Growers in warmer parts of Australia, especially far north Queensland, should not face these problems at all. It should be noted that Jade Perch are very well suited to grow-out in recirculating systems. They make an excellent beginners species, and are ideal for aquaponics.
Pond grown fish have large quantities of fat within their body cavity.
This fat is also present in Silver Perch grown in ponds, however Jade Perch have a little more of this fat. Anglers who have caught and eaten these fish from the Barcoo River also report seeing a large “lump” of fat in the gut of the fish. The fish comes from a very hostile environment. Fish in Australian rivers must be able to cope well with the “feast and famine” nature of the rivers systems in this country. After flooding the natural food supply for these fish is abundant. This glut of food is a contrast in the extreme compared to a drought situation where the fish will find getting a feed very difficult. Also during winter (usually the dry season) the fish are relatively inactive and probably rarely feed.
The stored fat will be used to help the fish survive in these situations. In aquaculture, fish are grown in an artificial environment such as a commercial fish pond or a recirculating system. They are in fact being kept in a “feast” situation. The fish grow rapidly and store fat as quick as they can, to be ready for the “famine”, which never comes. If your market finds this fat undesirable, perhaps a low protein, low fat, diet and a reduction in food will reduce the level of fat produced by your crop of fish.
It is our belief that a reduction in the frequency of feeds will also help. Reducing the food while the temperature is high should result in the fish burning up its fat reserves. Probably the optimal temperature for growing this fish is around 27C. Once the fish reaches your desired market weight try keeping the temperature up while reducing the feed intake. For every 10 degrees Centigrade the fishes metabolic rate is doubled. Therefore they burn up energy at twice the rate. You should also be aware that the fishes need for oxygen is also doubled.
The Jade Perch will grow on a wide variety of diets. Omega-3 content of the flesh varies with the diet used. Omega-3 highest in jade perch.
Jade perch and their spots
Jade perch are well known for their black spotting. These spots vairy from fish to fish. Some fish have many spots, some have only a few, or none at all. The spots can be any size and in any position on the fish. Each side of an individual fish will be different.
See the pictures below showing many individual fish and their spots. Click picture for a closer look.