Farming Yabbies

There are many species and strains of yabbies in Australia, including Cherax albidus , the type farmed in Western Australia. The yabby Cherax albidus was first introduced to WA in 1932 near Narembeen, when a farmer placed 10 yabbies, which he had brought back from Merwyn swamp in Victoria, into his dam (Morrissy & Cassells 1992). The yabby has since been spread from Esperance to the Hutt River, north of Geraldton, and into the Pilbara region. Unfortunately, these yabbies were misnamed as "koonacs", which is the correct name for a native swamp crayfish in WA.

The Department of Fisheries produces a brochure with coloured photos and descriptions of the various crayfish species in this State, to assist in correctly identifying yabbies and koonacs, this is available online here . Unauthorised stocking of freshwater crayfish from interstate is prohibited and poses significant disease and environmental risks.

Unique Ecosystem

The unique freshwater ecosystems of the remaining relatively pristine areas of WA's south-west and the biodiversity of the aquatic fauna found there, particularly the native freshwater crayfish including marron, need to be protected against introduced, exotic species such as yabbies. At the same time, yabbies are a valuable commercial export species.

Fortunately, there is plenty of scope for yabby farming in the inland agricultural region (the wheat belt) where yabbies thrive in clay-based farm dams. Farmers do not need a licence from the Department of Fisheries to farm yabbies provided they are the owner or occupier of the land and only sell to the holders of aquaculture, trapping or processing licences. Yabbies may be farmed in all areas north of Perth and, for areas south of Perth, to the east of an ecological boundary which is defined by the inland margin of State forest .

However, movements within this yabby zone are regulated to allow for disease management. Commercial yabby farming is not permitted to the west of this boundary.  

Wheatbelt Production

Yabby farming in the wheat belt is verysuccessful with annual total production fluctuating between 100 and 300 tonnes depending on rainfall. The production system is quite simple, with a relatively low yield per unit area of water, but total production is significant because yabbies are easily harvested with baited traps from many dams. The cost of farming is low because existing dams, built for the watering of stock, are used and the yabby stocks are essentially self-reproducing, wild populations.

This farming is at the lowest and easiest level of aquaculture, called "extensive". Farmers occasionally provide some supplementary feed for the yabbies in dams and the muddy water hides the yabbies from predators such as cormorants. Otherwise, production is not enhanced by the day-to-day management or use of costly equipment found in more intensive levels of fish culture.

Many unsuccessful commercial attempts have been made to farm yabbies more intensively (like marron) in purpose-built ponds, but costs and uncontrollable early breeding during grow-out were identified as obstacles to success. Since then, the Department of Fisheries researchers have overcome many of these obstacles (Lawrence et al. 1998).

Post Harvest Handling

Commercial trappers and processors have greatly improved post-harvest handling procedures. Despite the low production costs of farm dam harvesting, considerable costs are involved in purging, processing and packing the high- quality live yabbies which brings the highest market price particularly for export. Processors have established markets for yabbies larger than 30g and pay farmers higher prices for larger animals .

Yabbies are cold-blooded animals and their activity slows during winter, so few will enter baited traps at this time. The result is that the supply of yabbies from dams is largely confined to the warmer months of the year. Some farmers have constructed purpose-built ponds so they can continue to harvest their yabbies throughout the winter months.

Market Advantages

One of the main advantages of yabbies is that they can be exported alive, out of water and arrive in prime condition at high value markets in Europe and Asia. Internationally, the demand for freshwater crayfish is expected to continue to increase.

This increase is due to a number of factors, including strong demand by countries with traditional consumption of freshwater crayfish in Europe, plus decreased supply due to a disease (called 'crayfish plague') which has killed many of Europe's native populations of freshwater crayfish.

Australia is the only remaining continent which has freshwater crayfish not infected by this disease, and our current strict importation ban on freshwater crayfish should preserve this situation.

Informtation courtesy of the WA Department of Fisheries