Báo cáo Nghiên cứu khoa học Intensive in-Pond raceway production of marine finfish: third six-monthly report

Ministry of Agriculture & Rural Development CARD Project Progress Report VIE062/04 Intensive In-pond Raceway Production of Marine Finfish MS7: THIRD SIX-MONTHLY REPORT 1. Institute Information Project Name Intensive in-pond raceway production of marine finfish Vietnamese Institution Nha Trang University (the former University of Fisheries) Vietnamese Project Team Leader Dr. Hoang Tung Australian Organisation Queensland Department of Primary Industries & Fisheries Australian Personnel Mr Michael Burke Date commenced 15 April 2005 (01 August 2005 in Vietnam) Completion date (original) 15 April 2007 Completion date (revised) December 2007 Reporting period 01 Sept 2006 – 28 Feb 2007 Contact Officer(s) In Australia: Team Leader Name: Mr Michael Burke Telephone: +61 7 34002051 Position: Biologist Fax: +61 7 34083535 Organisation DPI&F Email: Michael.burke@dpi.qld.gov.au In Australia: Administrative contact Name: Michelle Robbins Telephone: +61 7 3346 2711 Position: Senior Planning Officer, R&D Coordination Fax: +61 7 3346 2727 Organisation DPI&F Email: Michelle.robbins@dpi.qld.gov.au In Vietnam Name: Dr. Hoang Tung Telephone: +84.914 166 145 Position: Director, International Centre for Research and Training Fax: +84.58.831145 Organisation Nha Trang University Email: htunguof@gmail. com 2 2. Project Abstract This project aims to develop the larval rearing and nursery capacity of marine finfish production in Vietnam through the use of accessible, cost effective and environmentally sustainable technologies. Through the development and use of in pond floating raceways (FR) this project will assist farmers to develop their own intensive but durable and manageable larval rearing capacity. This capacity will be used to improve fingerling supply to the industry which is currently both costly and limited. In addition, advanced nursery capacity will also be developed using the same principles. Grow out of finfish in raceways to market size will also be investigated in this project in conjunction with Australian researchers. Researchers from the Queensland DPI&F will provide expertise in systems management, water quality management and waste remediation. Species proposed for study include grouper, cobia and barramundi. All activities will be conducted using ‘zero discharge’ principles where there is no net discharge of effluent. Information from these activities will be used to train staff from the UoF, its students, industry and other relevant stakeholders. Active involvement and contribution of different stakeholders will make this research highly relevant and applicable to the local aquaculture industries. 3. Executive Summary In Australia, the first harvest and market appraisal was completed. Nursery raceways were successful in producing sand whiting (Sillago ciliata) in densities up to 70 kg/m3. This equates to a biomass of approximately 250 kg per unit. Whiting can reach market size (for the butterfly fillet market: 80 g) in 9 months. Growout raceways produced mulloway (Argyrosomus hololepidotus) at densities up to 100 kg/m3. This equates to a total biomass of 2,000 kg per raceway. Mulloway were grown to market size in less than 10 months (100 g -500 g). On-grown mulloway to 1 kg size took 14 months (170 g – 1000 g). Both species were well received in the market. Total fish production within the pond at BIARC exceeded 35 ton/ha equivalent, however this was achieved only with continuous water exchange (approx 10%/day) to regulate water quality. Next stage research will investigate water remediation strategies to progress towards zero water discharge and these trials have commenced. The successful demonstration of the raceway system at BIARC has provided baseline production efficiencies and guidelines for several new developments, including fish culture in municipal wastewater ponds and in extracted groundwater. The project has presented two posters at the World Aquaculture Society 2007 Annual Meeting in San Antonio, USA. Negotiations are continuing with commercial operators, Gold Coast Marine Aquaculture, to include cobia (Rachycentron canadum) trials this year and the Northern Fisheries Centre to include estuary cod (Epinephelus coioides). In Vietnam, trials to nurse barramundi (Lates calcarifer) from 20 mm total length to circa 80 – 100 mm total length were continued to show good results. Large fingerlings were provided to local farmers for stocking in ponds and cages. Positive feedbacks from the local farmers continue to inspire the project works. Nonetheless, the local’s lack of experience in farming barramundi at commercial scale appeared to marginalize project impacts. A preliminary trial was also conducted for barramundi grow-out in floating raceways as requested by CARD at the start of the project. With 3 assistance of the Australian Project Leader the project had conducted a workshop to disseminate project’s outcomes and drew in substantial interest of local farmers, extension officers and staff and students of Nha Trang University. Attempts to introduce the use of floating raceways to the adjacent provinces were also made. The project has presented two papers at the World Aquaculture Society 2007 Annual Meeting in San Antonio, USA. Preparations were undertaken so that the second year trials on zero-discharge system could be conducted. Limitations of the first floating raceway model (called SMART-1) were identified and addressed by the design and construction of a new version called SMART-2 that allows full-scale commercialization of floating raceways for marine finfish fingerling production, particularly with species like cobia (Rachycentron canadum) and groupers (Epinephelus spp) in Vietnam. The project will be working with local farmers and extension organizations to trial SMART-2 and at the same time testing the possibility of developing a zero-discharge system using floating raceways. 4. Introduction & Background Aquaculture plays an important role in the development of Vietnam’s economy and has been widely considered as an effective means for poverty alleviation by the FAO. The country aims to produce 2 million tons of aquaculture products, mainly with marine species, by 2010. This ambitious target is unlikely to be achievable unless cost-effective methods of nursing are developed to produce large number of large fingerlings for stocking in sea cages and coastal ponds. As tank production of large fingerlings is highly costly, other option such as nursing in earthern ponds, hapas and floating raceways should be considered. In this regard, the floating raceway technology has a number of unique advantages over all the other systems, including effective management, high productivity and high level of biosecurity. In Queensland marine fish farming in sea cages is considered as damaging to coral reefs and other sensitive aquatic habitats. New sustainable yet profitable land based production methods are thus in need for development. Tank based marine recirculation facilities are cost prohibitive and would fail to take advantage of Queensland’s favourable climate and existing pond aquaculture infrastructure. The combination of floating raceways and bioremediation would eventually result in “low- discharge” or even “zero-discharge” system for coastal aquaculture. This CARD project combines the innovative design of floating raceways (FRs) with the concept of bioremediation. FRs, either made of plastic or cheap materials, have been trialled successfully in Japan, Australia and US. Through this project, different local materials have been used to design and built raceways, at both commercial and experimental scales for trials. Target species include high-value indigenous fish such as barramundii, whiting, snapper, cobia, murray cods, etc. The project also emphasizes on improving capacity of the Vietnamese institutions through study tour, training courses and research internship. Information from the project once available is immediately disseminated to local farmers and the industry through extension workshop. The system is designed in a form that allows it to be used by farmers with no major change of their existing ponds. This project is expected to help boosting production of marine fish fingerlings and better use the existing shrimp ponds, many of which are abandoned in coastal areas. These fit nicely into the CARD’s framework and aims, i.e. promoting productive technology addressing social, environmental and human resource development issues. 4 5. Progress to Date 5.1 Implementation Highlights • Carrying capacity and most suitable stocking densities for growout determined for whiting and mulloway based on growth rate, FCR and fish health. Total production capacity from experimental raceways at BIARC equivalent to 35 tons/hectare. • First harvest and market appraisal of harvested whiting and mulloway in Australia. Both species well received. Raceways restocked for fish to be on- grown for future growth rate, FCR and harvest data. • Trials underway in Aust to progress towards zero discharge from floating raceway production ponds. Remediation strategies to be investigated include: (a) evaluation of waste sumps within raceways to collect uneaten feed and faeces; (b) the culture of harpoon weed (Asparagopsis armata) as a nutrient sink; and (c) the promotion of bacterial flocs for managing pH and waste nutrients. • Trials on using floating raceways (SMART-1) for advanced nursing of barramundi were complete. Shrimp pellets have been used successfully for nursing barramundi, which helps simplify farming protocol as specially- made pellets for barramundi are not available yet on market in Vietnam. • A preliminary trial was conducted to assess the possibility of using floating raceways for grow-out production of marine fish in Vietnam as advised by CARD at the start of the project. • First MSc student, supervised and supported by the project, successfully defended his research thesis and graduated in December 2006. Experimental design and proposal development are being undertaken for the second MSc student. • An extension workshop was organized for more than 150 attendants (local farmers, extension officers, teaching/research staff and students of Nha Trang University) in December 2006. • First year project meeting was held in Nha Trang with attendance of the Australian Project Leader. The team later was visiting Phu Yen Province and a number of governmental and private enterprises to introduce floating raceway technology and received great interest. • The project had designed and manufactured a new version of floating raceway called SMART-2 for trials in the second year. This SMART-2 model is aimed for commercial production of cobia and grouper fingerlings. Negotiation has been made to trial SMART-2 in collaboration with local farmers and the Binh Dinh Fisheries Extension Center, Binh Dinh Province. • One paper about project outcomes was presented at WAS 2007 in San Antonio, Texas, USA in Feb 2007. One paper was submitted to the organization committee of the IMOLA Symposium – Integrated Farming Approach which will be held at Hue Agriculture and Forestry University in April 2007. One paper was submitted to the Journal of Fisheries Science and Technology in Vietnam for publication in July 2007. • Trial on the development of a zero-discharge system was undertaken. 5 5.2 Smallholder Benefits In Australia: • Integrated Recycle International Ltd (IRI) has adopted a modified raceway design for a new Queensland enterprise that aims to produce fish in wastewater for fishmeal production. The raceway design is based on the low-cost HDPE configuration developed in this CARD project. The IRI venture will be established at Hervey Bay on Queensland’s Fraser Coast, and will utilise water stored in municipal tertiary treated effluent ponds managed by the local government authority. Preliminary trials have identified a suitable native fish candidate, and work has commenced in building floating pontoon infrastructure. Floating raceways were selected as the preferred production system due to cost effectiveness and the improved management they offer in terms of stock inventory, growth and disease monitoring, predator control and harvesting. • A large prawn farm in North Queensland has requested specific information on raceway specifications for future diversification opportunities. Their interest lays particularly in the growout of reef fish species within existing prawn ponds. • The use of floating raceways for growing marine fish in ponds containing saline groundwater extracted from coal seam gas mining is currently being investigated, with much of the production modelling based on data generated in this CARD project. In Vietnam: • The Khanh Hoa Fisheries Extension Center had taken up quickly the project outputs and produced large fingerlings for local fish farmers in Khanh Hoa Province and some adjacent ones like Quang Ngai, Binh Dinh and Ninh Thuan. As barramundi seeds are currently supplied to the fish farmers at a small size of around 20 mm total length, larger fingerlings (80 – 100 mm total length) clearly associates with higher growth rate and higher survival rate in grow-out ponds. • Around 150 local farmers, extension officers, students and staff of Nha Trang University received instruction/advices for the application of floating raceways into aquaculture production through the first year workshop organized by the project at Nha Trang University in December 2006. • The Vietnamese Project Leader has consulted the Australian Project Leader and finalized negotiation with two farms in Khanh Hoa Province (one in Cam Ranh and the other in Nha Trang) and the Department of Fisheries of Binh Dinh Province to collaborate in testing SMART-2 at commercial scale. Raceways will be provided by the project and trials will be run at the expenses of the collaborators. • Discussion was also made with Department of Fisheries of Phu Yen Province to trial floating raceways for growing out freshwater eels in Song Hinh Reservoir. 5.3 Capacity Building In Australia 6 • Additional staff members from BIARC have been trained in the construction and function of floating raceways. These include Dan Willett and Trevor Borchert. • In collaboration with industry, several cobia broodstock have been collected and maintained at BIARC with plans to expand the broodstock numbers further. These fish are being domesticated and conditioned for future reproduction and growout trials. The raceways will be investigated as nursery facilities for weaned fingerlings. In Vietnam • Staffs of Nha Trang University and Khanh Hoa Fisheries Promotion Center are involved in project activities, thus improving skills and knowledge of marine fish nursing and pond management. • The Vietnamese Project Leader and his research colleagues at NTU and KFPC are able to write and publish project outcomes at international conferences and in national journal. • Information and project results were incorporated into lectures of three subjects namely “Research Methodology in Aquaculture”, “Experimental Design and Data Analysis” and “Coastal Aquaculture Systems” offered to undergraduate and graduate students at NTU. 5.4 Publicity • The demonstration of marine fish (mulloway and whiting) growout at high densities in raceways at the trial site at BIARC continues to attract attention of visiting research institutions and commercial aquaculture operators. • The project has presented two posters at the World Aquaculture Society 2007 Annual Meeting in San Antonio, USA. • Information about the project has been prepared by the research team and available at the website of Nha Trang University under the International Center for Research and Training (www.ntu.edu.vn). • One extended abstract titled “Nursing marine fish in coastal pond using floating raceways” by Tung Hoang, Mao Nguyen, Adrian Collins and Michael Burke was submitted to WAS 2007 Conference in US. • Two articles were submitted for publication in Vietnam. • The Vietnamese Project Leader and Australian Project Leader have jointly promoted floating raceway technology in Khanh Hoa and Phu Yen Province. 5.5 Project Management • Project staff changes at BIARC have been managed after the resignation of technicians Scott Shanks and Blair Chilton. Luke Dutney and Stephen Nicholson have now been instated to conduct daily on-ground activities of the project. Both have considerable aquaculture experience and have been trained in all technical aspects of the project. • The Australian Project Leader, Mr. Michael Burke has actively led the project and provided great supports to the Vietnamese Component. • The second six-month report was submitted to CARD and approval was granted consequently. Milestone reports (3&4) were prepared and submitted to CARD. 7 • Routines for information exchange have been practised between the Australian and Vietnamese project leaders. • Funding transfer has been made available and sufficient by QDPI&F for NTU to conduct trials as planned. 6. Report on Cross-Cutting Issues 6.1 Environment For research activities in Vietnam environmental concern is not an issue as the system is designed with minimum water exchange with the surrounding environment. In fact, the pond water has been used for seven months already with no exchange. Apart from the only incident encountered in early July (due to wrong practice of one project technician), water quality in the reservoir pond has been adequately good for the fish in the floating raceways. In the second year of the project, detailed studies on nutrient budget of the system will view more information and confirm the possibility to develop a “zero-discharge” system that remedies possible environmental impacts and improves its biosecurity. In Australia the promotion of raceway technology will also need to address environmental compliance issues. While our research has demonstrated that raceways facilitate higher production efficiencies per hectare, uptake of the technology by existing coastal pond-based farmers will be restricted unless there are strategies for minimising nutrient discharge. This is because of State EPA discharge regulations. Research activities for this period are focussing on this issue with trials evaluating waste collection sumps within raceways, seaweed biofiltration and the use of bacterial-based ‘biofloc’ treatment to progress towards zero water discharge. 6.2 Gender and Social Issues In Vietnam daily management of the nursing system showed that the system requires continuous attention rather than hard works. This may facilitate further involvement of women in aquaculture. Within the scope of the project alone two ladies are involved in experimental works. However, high level of intensification and high productivity of this nursing system will limit the number of farms to adopt it. The social benefits should be considered as more quality fingerlings are made available to fish farmers. 7. Implementation & Sustainability Issues 7.1 Issues and Constraints • Due to increasing competitive pressures from cheap imported products, many Queensland farmers are looking to make better use of existing farm infrastructures through growing complementary species. The use of floating raceways as part of an integrated grow-out system should allow farmers to take advantage of multiple production ‘niches’ within the system (e.g., higher 8 order fish within raceways and detritivores such as shrimp or mullet free- ranging in the pond). This potentially increases yield per area and per feed input. However, waste nutrient generation and discharge remain constraints to increasing yields/hectare in Australia. • The availability of seed at expected time (for trials) is considered as challenge, particularly with species that are not produced in Khanh Hoa Province such as cobia and groupers. Arrangements have been made with supplier from the North, but reliable supply is still questionable. • Floating raceways appear to be an excellent option for advanced nursing of marine finfish. However, it will take time for the technology to be adopted by local farmers and governmental enterprises. The intensive nature of floating raceways implies high investment on operating costs, mainly for the stocked fish. This is an inhibitory factor to small-scale farmers. Also, it will take time for local fish farmers recognize the importance of larger fingerlings for stocking after a number of crops. This is something that can only be proven through their own experiences of farming fish. No marketing measures nor educational materials could help. 7.2 Options • Flexibility in species of choice given ample justification provided. • Investigate biofloc technologies as a option to better manage high pond nutrient levels and reduce the need to discharge water to the environment 7.3 Sustainability • Appeared not to be an issue as more interested parties involved in the project. Already in Vietnam the number of provinces that are interested in this new technology keeps increasing. • In Australia, new uses for raceway production systems are being developed, including fish culture in municipal wastewater ponds and in extracted groundwater. The successful demonstration of the raceway system at BIARC has provided baseline production efficiencies and production guidelines for these new developments. 8. Next Critical Steps In Vietnam (for the period from Feb to Aug 2007) • Conduct trial on zero-discharge system and continue trials on cobia and groupers. • Discuss plans and supervise the second MSc student. • Finalize plans for the final extension workshop in Vietnam. It is possible to organize this in the form of an exhibition booth at the Asian Pacific 2007 Aquaculture Conference in Hanoi in August 2007 in parallel with some presentations in the marine finfish session. • Submit manuscripts for publication at international/national conferences and journals/magazines. • Complete all reports of the project, particularly the Final Report. • Continue to promote floating raceway technology in Vietnam. 9 • In Australia (for the period from Feb to Aug 2007) • Continue investigations into (and report on) water remediation strategies that can limit water discharge and make raceway production of fish sustainable. • Finalise production figures of whiting and mulloway in raceways and marketing appraisal of harvested stock. • Continue to promote floating raceway technology in Australia. 9. Conclusion Project is progressing according to plans in both Australia and Vietnam. 10