Evaluation of two species, Cobia and Giant Grouper, as alternative species to farm in the WSSV affected areas of South East Queensland

In 2016/17, the Rocky Point Prawn Farm, along with other farms in the Logan River region of south-east Queensland, was severely affected by a white spot disease outbreak caused by the exotic white spot syndrome virus (WSSV). Measures enforced to eradicate WSSV resulted in a complete loss of stock and a ban on prawn production within the Logan River and wider Moreton Bay area until May 2018. As a result, Rocky Point Prawn Farms (RPPF) elected to investigate the feasibility of finfish aquaculture as an alternative to prawn farming. The current project was undertaken to assess the potential of two finfish species, Cobia (Rachycentron canadum) and Giant Grouper (Epinephelus lanceolatus) as alternative aquaculture candidates for the Rocky Point Prawn Farm and potentially other aquaculture enterprises. The study was developed and led by RPPF with assistance from The Company One (TCO) and the Department of Agriculture and Fisheries (DAF), with staff from the Bribie Island Research Centre (BIRC) and ran from March 2017 until June 2018. In the study, the commercial performance of each species was assessed when cultured in both indoor tank systems and outdoors in cages. Culture facilities at two of RPPF’s production sites included a former prawn hatchery building which housed the indoor tank-based production, and an outdoor landlocked saline lake which contained cages. Cobia fingerlings were produced at BIRC and Giant Grouper fingerlings were supplied by TCO hatchery in Cairns. All fingerlings were initially grown in indoor tanks under controlled temperature conditions and later some were transferred to outdoor cages to assess their performance in both winter and spring/summer. Fish were fed once or twice per day and water quality data was collected daily. Weight and health checks were conducted monthly and any mortalities were removed from tanks or cages daily. The data were used to calculate key production parameters of feed conversion ratio, growth rate and survival throughout the production cycle. Both species were grown to harvest and sold into the domestic market. The production and market information generated by this project provided a framework to evaluate the relative costs and benefits of the two species within the range of production methods and strategies available to RPPF, and guidance towards future investment and optimising production in the future

Commercialising the production of Cobia in Australia

This project is a collaboration between the Department of Agriculture and Fisheries (DAF) and the Cobia aquaculture sector, predominantly Pacific Reef Fisheries (PRF). It was undertaken to consolidate the aquaculture in Australia of Cobia, a species offering considerable potential as a diversification option for pond-based culture activities in Queensland. The project addressed key elements of the production cycle in order to move industry towards a more commercial footing and advance both the scientific knowledge and human capabilities of the sector. The project involved DAF staff at the Department’s Bribie Island Research Centre (BIRC) and staff from the PRF farm in Ayr, North Queensland. From 2014-2017, research examined: health issues affecting Cobia in culture both in the hatchery and on-farm; the emerging issue of intersex in Cobia and potential for this to further impact production; capability development of PRF staff in preparation of the establishment of a commercial Cobia hatchery; and, the involvement of some new entrants to Cobia aquaculture utilising tank-based production systems

Can Orchards Help Connect Mediterranean Ecosystems? Animal Movement Data Alter Conservation Priorities

As natural habitats become fragmented by human activities, animals must increasingly move through human-dominated systems, particularly agricultural landscapes. Mapping areas important for animal movement has therefore become a key part of conservation planning. Models of landscape connectivity are often parameterized using expert opinion and seldom distinguish between the risks and barriers presented by different crop types. Recent research, however, suggests different crop types, such as row crops and orchards, differ in the degree to which they facilitate or impede species movements. Like many mammalian carnivores, bobcats (Lynx rufus) are sensitive to fragmentation and loss of connectivity between habitat patches. We investigated how distinguishing between different agricultural land covers might change conclusions about the relative conservation importance of different land uses in a Mediterranean ecosystem. Bobcats moved relatively quickly in row crops but relatively slowly in orchards, at rates similar to those in natural habitats of woodlands and scrub. We found that parameterizing a connectivity model using empirical data on bobcat movements in agricultural lands and other land covers, instead of parameterizing the model using habitat suitability indices based on expert opinion, altered locations of predicted animal movement routes. These results emphasize that differentiating between types of agriculture can alter conservation planning outcomes

Evaluation of two species, Cobia and Giant Grouper, as alternative species to farm in the WSSV affected areas of South East Queensland

In 2016/17, the Rocky Point Prawn Farm, along with other farms in the Logan River region of south-east Queensland, was severely affected by a white spot disease outbreak caused by the exotic white spot syndrome virus (WSSV). Measures enforced to eradicate WSSV resulted in a complete loss of stock and a ban on prawn production within the Logan River and wider Moreton Bay area until May 2018. As a result, Rocky Point Prawn Farms (RPPF) elected to investigate the feasibility of finfish aquaculture as an alternative to prawn farming. The current project was undertaken to assess the potential of two finfish species, Cobia (Rachycentron canadum) and Giant Grouper (Epinephelus lanceolatus) as alternative aquaculture candidates for the Rocky Point Prawn Farm and potentially other aquaculture enterprises. The study was developed and led by RPPF with assistance from The Company One (TCO) and the Department of Agriculture and Fisheries (DAF), with staff from the Bribie Island Research Centre (BIRC) and ran from March 2017 until June 2018. In the study, the commercial performance of each species was assessed when cultured in both indoor tank systems and outdoors in cages. Culture facilities at two of RPPF’s production sites included a former prawn hatchery building which housed the indoor tank-based production, and an outdoor landlocked saline lake which contained cages. Cobia fingerlings were produced at BIRC and Giant Grouper fingerlings were supplied by TCO hatchery in Cairns. All fingerlings were initially grown in indoor tanks under controlled temperature conditions and later some were transferred to outdoor cages to assess their performance in both winter and spring/summer. Fish were fed once or twice per day and water quality data was collected daily. Weight and health checks were conducted monthly and any mortalities were removed from tanks or cages daily. The data were used to calculate key production parameters of feed conversion ratio, growth rate and survival throughout the production cycle. Both species were grown to harvest and sold into the domestic market. The production and market information generated by this project provided a framework to evaluate the relative costs and benefits of the two species within the range of production methods and strategies available to RPPF, and guidance towards future investment and optimising production in the future