Pond and Paddock

Commercial redclaw crayfish production

The AquaCon team have focussed on the commercial production of redclaw crayfish for domestic and export markets with the goal of zero discharge into the surrounding environment. To achieve this outcome, several projects were undertaken:

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1. Earthen culture pond design - Advancement of large earthen pond design to facilitate commercial scale production of redclaw crayfish.
2. Bioremediation systems - The implementation of bioremediation systems to process aquaculture waste and to ensure zero discharge into the surrounding environment. Bioremediation systems enabled the majority of the water to be recirculated through the culture ponds without compromising high standards of water quality.
3. Diet - Commercially available feeds provide only part of the required food profiles for redclaw crayfish. Through dietary supplementations and improved feeding techniques yields and feed efficiency could be optimised to increase the production of redclaw crayfish. Initial results were promising, and the team is confident that with further trials and new technologies available, yields could be further improved through feeds.
4. Transportation – Live crays are often transported to customers on long flights domestically and internationally. Through the development of best practice purging and transport protocols including optimal transport temperature, density, safe transport time and other factors, the quality of the product arriving to customers was improved. The team have continued to explore methods and products to further optimise all steps of this process and improve the quality of the market ready product.
5. Monosex populations – There is evidence of yield increases when males and females are kept separate for grow-out, however separating the sexes can be a costly exercise. The production of female only offspring initially with the intent of producing male only offspring was the primary goal. As this was a multi-generational trial, the outcomes were inconclusive and called for further investigation. AquaCon plan to use computer vision and AI to automatically separate sexes at juvenile size to significantly decrease labour cost and stress to the animals.
6. Habitat availability in ponds - Hard and soft habitats are commonly used in culture ponds, however the optimal number of habitats varies considerably and is mainly based around qualitative data. The project aimed to determine the correct design, layout and number of soft and hard habitats required for the pond culture of redclaw crayfish while also balancing the financial viability of habitat cost, labour and production yields. Results on the site were inconclusive, possibly due to other confounding variables, further trials are required to fully assess the habitat/yield relationship.
7. Production intensification - Intensification of juvenile production of redclaw crayfish by adding dedicated nursery ponds and a nursery phase to the farm production cycle meant that the nursery phase and production of juveniles could be intensified freeing-up more pond area for dedicated grow-out, improving profitability and control over harvest cycles and production. This process was implemented early and run through several cycles with varying results. Further trials are required to fully assess the viability of this production method.
8. Probiotics - Probiotics for enrichment of pond environment and remediation of wastewater. These probiotics were designed to provide these ecosystem services, while also producing a food source for crays from waste material in the ponds. Early results were promising for improved yields and increased financial viability however the AquaCon team will be continuing this work as the benefits found reflected considerable yield increases.