FAQs
What is prawn farming?
Prawn farming is the growing of prawns in land based purpose-built pond structures for human consumption. In Australia, farms are located primarily in Queensland with a few small farms in New South Wales and the Northern Territory. The two main species farmed in Australia are Black Tiger prawns (Penaeus monodon) and Banana prawns (Penaeus merguiensis). These are marine species and therefore farms are located on coastal land or adjacent to the estuarine part of river systems. Baby prawns, known as post-larvae, are bred in hatcheries and stocked into farm ponds where it takes approximately 5-6 months for prawns to grow to market size (20-50 g). All current prawn farms in Australia adopt semi-intensive farming practises. This means prawns are stocked at densities of 25 – 50 prawns/m2 and requires supplementary feeding of commercial pellets supplied throughout the crop. Careful management of the pond water through water quality monitoring, mechanical aeration and water exchange are required to maintain healthy prawns. Therefore, this type of farming, semi-intensive, requires high capital, high labour and technical expertise. More information about prawn farming can be found under Useful Resources below. An alternative farming model we believe is more suited to remote areas of northern Australia is extensive farming.
How does extensive prawn farming differ from existing prawn farms in Australia?
Extensive prawn farming is currently not practised in Australia but is used throughout south east Asia and Latin America. Extensive prawn farming is based on lower intensity production. Meaning fewer prawns are stocked in ponds, usually <5 prawns/m2, there is no or limited supplementary feeding as prawns rely on the natural food occurring in ponds. These features of extensive prawn farming mean annual productivity is lower and income per hectare is less compared to semi-intensive prawn farms. However, the capital requirements for extensive prawn farms are less and there is a lower requirement for day-to-day maintenance and technical expertise. Making extensive prawn farming lower risk for potential new aquaculture business in northern Australia.
What’s involved in constructing an extensive prawn farm?
Extensive prawn farms, like other aquaculture developments, are subject to building and development approvals as well as environmental impact assessments. The proposed extensive prawn farm would be required to obtain all the necessary approvals and permits.
Site location is important for constructing a prawn farm, the ponds are situated are above the intertidal zone. Earthworks are required to construct shallow (1.5 m deep) earthen based pond structures 1-2 ha in size. The soil that is removed to form the ponds is used to construct the pond walls or embankments and typically not removed from the site. The soil characteristics at the site are important as the soil within the ponds needs to form an impermeable layer between the pond water and surrounding surface and groundwater. More information on specific site suitability features can be found in the EOI Guidelines.
Other important structures on the farm include bioremediation ponds, water pumps and storage facilities. Bioremediation ponds are constructed in the same way as production ponds. The purpose of these ponds is to remediate wastewater from the production ponds by removing excess nutrients and suspended solids. Water is normally gravity fed from the production ponds to the bioremediations ponds and the resulting clean water can then be recycled for production or discharged to the environment. Mechanical water pumps are needed for pumping and transporting water from the source (i.e. river or ocean) to the production ponds and in some cases around the farm as well (e.g. from the bioremediation pond back into the production ponds). Storage facilities such as a shed to store and secure equipment is required.
Other facilities found on semi-intensive farms include hatcheries (for producing baby prawns otherwise known as post-larvae) and processing facilities. These facilities are not essential, as post-larvae can be sourced from other facilities (permits required) and harvested product can be processed offsite.
What are the potential environmental impacts of extensive prawn farming?
Environmental impact monitoring will form an important part of this initiative. Australian prawn farms are reported as being among the most environmentally sustainable in the world. Extensive prawn farming is considered an even more environmentally friendly model of farming due to the low intensity, low input methods used. Careful consideration and impact assessments of the site prior to development are required to obtain approvals. There is also a requirement for ongoing environmental monitoring such as monitoring of effluent water prior to and during discharge to the environment. Extensive prawn farming with its low input nature is unlikely to generate high amounts of waste and therefore have a lower requirement to discharge water to the environment.
Are prawn farms profitable?
Profit is dependent on many factors and can vary from changed conditions. For conventional semi-intensive prawn farms currently in operation in Australia, operating costs are high as are the capital costs in the start-up years before revenue from harvested product starts to be generated. Even small changes in quantities and the price of inputs and or sale price would have a relatively large impact on net profit margins. Despite this, prawn farming is and can be a profitable business.
Extensive prawn farms require much lower start up and ongoing operational costs as a result of the low intensity and low input farming model. The harvested product from extensive prawns could also attract a premium price due to the large size and other marketing strategies. Therefore, extensive prawn farming has the potential to be a economically viable business in Australia. However, this is the key objective of the pilot when assessing the viability of extensive prawn farming in northern Australia.
Why do we need a demonstration extensive prawn farm?
The primary goal of the initiative is to partner with an Indigenous organisation to co-design a demonstration extensive prawn farm. As this is a new approach to prawn farming in Australia, the purpose of the demonstration farm is to evaluate the viability of the extensive farming model for northern Australia. This type of prawn farming is practised internationally but has not been proven in northern Australia.