Đề tài Evaluation of contribution of floating raceway technology to the development of marine finfish farming in australia and vietnam - Milestone report no 8

Milestone report No.8 | CARD VIE062/04 PROJECT 1 Ministry of Agriculture & Rural Development PROGRESS REPORT Intensive in-pond floating raceway production of marine finfish (CARD VIE 062/04) MILESTONE REPORT NO.8 Evaluation of contribution of floating raceway technology to the development of marine finfish farming in Australia and Vietnam Tung Hoang1, Michael Burke2 & Daniel Willet2 1 Nha Trang University, Vietnam 2 Queensland Department of Primary Industries & Fisheries, Australia April 2008 Milestone report No.8 | CARD VIE062/04 PROJECT 2 PREFACE The CARD VIE062/04 Project “Intensive inpond floating raceway production of marine finfish” aimed to develop an innovative nursing and growing system for marine finfish, i.e. floating receways using existing pond farming infrastructrure in coastal areas of Vietnam and Australia. Started in August 2005 this project was expected to help develop marine finfish farming in both countries by increasing the production of large fingerlings of marine finfish in Vietnam and grow- out production in Australia. Since then the CARD VIE062/04 Project had maintained its efforts in both floating raceway technology development and extension services. This report is to highlight a number of immediate effects of the project on the local fish farming industries. The report has two parts: one for the Australian component and the other for the Vietnamese component. Needless to say that the short duration of the project, i.e. two years, is certaintly not enough for any ambitious goal, particularly when this new technology was still under development. The closing of the project in late 2007 was just the start of a process of introducing floating raceway technology extensively in the two countries. Thus, the impact of this new technology will become obvious in a few years. We would like to express our sincere thanks to the CARD Program, Queensland Department of Primary Industries & Fisheries, Nha Trang University, Khanh Hoa Fisheries Extension Center (KFEC) for their consistent supports to this project. Thanks are extended to Dr. Adrian Collins, Mr. Benjamin Russels, BIARC’ staff, Mr. Luu The Phuong, Mr. Ngo Van Manh, Mr. Huynh Kim Khanh, Ms. Banh Thi Quyen Quyen, the technicians working at the research station of KFEC in Ninh Loc and a number of BSc students at Nha Trang University who had dedicated their time and effort making this project a success in several aspects. The CARD VIE062/04 Project Team Milestone report No.8 | CARD VIE062/04 PROJECT 3 Part 1 Evaluation of contribution of floating raceway technology to the development of marine finfish farming in Australia 1. TARGET BENEFICIARIES AND DEMONSTRATED BENEFITS Beneficiaries of raceway technology development in Australia are principally from the growout sector. In particular, advantages have been identified for growout operations in non-specific and permanent water bodies (that is, water bodies not established especially for aquaculture including existing reservoirs and agricultural farm dams). In these situations, floating raceways were seen as the preferred production system due to cost effectiveness in construction and the improved management they offer in terms of stock inventory, feeding, growth and disease monitoring, predator control and harvesting. Several Queensland operators have either established or are investigating floating raceway use for these situations. While initial evaluations of this technology proposed its suitability for existing prawn farmers wishing to diversify into finfish growout, uptake in this sector has been limited to date, although some interest has been registered by two Queensland prawn farms. One possible disadvantage of this technology for prawn farms is that existing ponds are often shallow meaning that the raceways will be in close contact with the pond bottom. This interferes with preferred water flow patterns in ponds whereby currents are baffled by the raceway structure. The management of flow patterns in these ponds is important for controlling settlement of particulate matter, which in turn affects water quality management. This will become more of an issue as pond water exchange is reduced. Periodic draining of these small ponds (which occurs seasonally in prawn production for crop harvesting) is also standard practice for managing the build up of organic material. Draining ponds containing raceway infrastructure can be problematic with raceways constructed out of HDPE sheet material as it is unable to support the weight of the floating walkways out of water. In this case, at least partial dismantling or removal of the raceway components would generally be required if draining ponds. Our experience at BIARC has demonstrated that the marine raceways tended to accumulate epiphytic growth on surfaces. The airlift system was designed to be easily removed for cleaning; however the pontoon structure also requires periodic cleaning to remove fouling material, which is a significantly more difficult operation. The goal of the current CARD project was to develop a production system with low construction costs. While this project delivered an efficient and low cost system, many of these identified operational constraints could be rectified by modifying the raceway design; for instance, by using Milestone report No.8 | CARD VIE062/04 PROJECT 4 more rigid construction materials such as moulded plastic or fibreglass which was capable of supporting its own weight out of water. Of course, this would make construction costs significantly more expensive and the increased costs of a rigid raceway system may not necessarily be justified against the inconvenience of managing the flexible HDPE sheet raceways. This would be dependant on individual farm circumstances. SUMMARY Advantages • Cost effectiveness in construction. • Improved management in terms of stock inventory, feeding, growth and disease monitoring, predator control and harvesting. • Airlift system easily removed for cleaning • Ideal for non-specific water bodies where other aquaculture production systems are unsuitable Disadvantages • Can baffle water circulation in shallow ponds. • Flexible HDPE raceways need to be partially dismantled or removed when pond is drained. • Build up of epiphytic growth which requires periodic cleaning 2. TECHNOLOGY UPTAKE There has been considerable interest in this project’s demonstration of low-cost floating raceways for fish growout. The technology has been extended to local industry through presentations at the WAS 2006 Conference in Adelaide; at an Extension Workshop for state- wide Queensland Fisheries Service staff in October 2006; and at the Aquaculture Association of Queensland Conference in 2007. In addition, regular visiting groups to BIARC including government delegations, industry representatives and student groups have been briefed on the system. While it is expected to take some time to see the full flow of benefits to industry from this work, new uses for raceway production systems are being developed, including fish culture integrated within existing agriculture farms, in municipal wastewater ponds and in extracted groundwater. The following list details current specific interest and uptake of this technology in Queensland: • Kilcoy Fish Company (KFC) worked closely with CARD project staff to establish a floating raceway culture system within an existing 7 hectare water reservoir on a dairy Milestone report No.8 | CARD VIE062/04 PROJECT 5 farm. The system consists of a series of 40m3 growout raceways, each 12 m long and 2.4 m wide. System design was based on the low-cost HDPE configuration used in the CARD project (Fig 1). Fish species cultured include Murray cod (Maccullochela peelii) (Fig 2) and jade perch (Scortum barcoo). The farm has been successful in growing Murray cod at densities greater than 100 kg/m3 and has been selling fish to market since 2006. • Integrated Recycle International Ltd (IRI) has adopted a modified raceway design for a new large-scale 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. In this instance, fish will feed exclusively on natural productivity in the lagoon which is cycled through raceways via the airlifts 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 (Fig 3). Figure 1. Floating raceway system at the Kilcoy Fish Company’s farm. The design was based on the low-cost HDPE configuration used in the CARD project. Milestone report No.8 | CARD VIE062/04 PROJECT 6 Figure 2. Murray cod grown in the floating raceway system at the KFC farm. Figure 3. Aerial view of the floating raceway system under construction at Hervey Bay, Queensland as part of the IRI fishmeal production project. Fifty-four HDPE raceways, each 58 m3 capacity, will be suspended between the floating pontoons. • 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. • Seafarm, a large prawn farm in North Queensland, has requested specific information on raceway specifications for future diversification opportunities. Their interest lays Milestone report No.8 | CARD VIE062/04 PROJECT 7 particularly in the growout of reef fish species within existing prawn ponds and intake channels. • Gold Coast Marine Aquaculture (GCMA), a large prawn farm on the Logan River in South Queensland, is collaborating with BIARC staff to develop cobia (Rachycentron canadum) production. BIARC staff are currently holding 16 broodstock for planned fingerling production trials in 2008 with weaned fingerlings to be sent to GCMA for growout. Floating raceways will be trialled as the preferred growout facility. 3. ECONOMIC ANALYSIS/COST OF PRODUCTION Floating raceways, as demonstrated by the technology uptake above, have diverse application ranging from freshwater, inland saline groundwater and marine growout of high quality table fish for human consumption to mass production of lower order detritivorous fish in wastewater for fishmeal production. Because of these diverse applications and varying economies of scale, sizes of raceway infrastructure and feeding requirements it is difficult to generalise on costs of production. For instance, this technology has been adopted by IRI Ltd who has plans to grow detritivorous fish in municipal wastewater for fishmeal production. Here fish will feed exclusively on natural productivity in the lagoon which is cycled through 54 large (58m3) raceways via the airlifts. This means that feed expenses are removed from the production costs; however, the product (as a commodity) will achieve a lower market price and the operation relies on economies of scale in the order of 600 tonnes/year production to be profitable. For the current evaluation, however, the more generic use of raceways for medium value finfish production (such as barramundi) is considered. Based on Australian conditions, our estimations of running costs, capital set up and depreciation, labour, feed inputs and operating we have determined that raceways are an economically viable alternative for grow-out production of marine finfish but again, like all systems, there needs to be an economy of scale and regular supply to good markets. In our estimation, and based on previous experience with the barramundi industry in Australia, it is proposed that an aquaculture operation needs to produce at least 1000 kg/week for market to gain production efficiencies. This equates to 26 grow-out raceways of the size used in the current trial (20m3). This production level would establish an aquaculture operation in the market place and would demand competitive buying and selling power. Currently our best estimate for cost of production in trial raceways is approximately AUD$8/kg. This will improve over time and compares well with other production systems but without the large capital input. One of the tangible advantages of raceway production is the lack of initial capital set up costs for ponds or recirculation operations which frequently run into the 100’s of 1000’s of $AUD for relatively small operations. Raceways are designed to be self contained production units requiring only a supply of air and a body of water (of appropriate quality) to float them in. Milestone report No.8 | CARD VIE062/04 PROJECT 8 Construction costs will also reduce as large scale production develops and raceway size is progressively made larger. This is evident from just our simple comparison of Grow-Out Raceway construction costs ($130/m3) Vs Nursery raceway construction costs ($335/m3). Labour costs will also reduce comparatively with larger system and more economy of scale. The barramundi industry in Qld currently utilises 1 FTE per 16 ton of barramundi produced. Our raceway trial utilised the equivalent of 1 FTE for the production of 10 ton (Table 1). This is a good achievement for a new experimental system to come close to other production systems that have been in place for many years, and with increasing economies of scale this would be further improved. Table 3. Routine Labour Requirement for 4 x Nursery and 2 x Grow-out Raceways at BIARC. Procedure Frequency Time (hrs/week) Water Quality/Pond Management 2 x Daily 4.25 Feeding 2 x Daily 7.5 Cleaning intake/outlet screens 2 x weekly x 6 units 4.5 Cleaning uplifts 1 x month x 6 units 2 Total Routine Labour 18.25 hrs/week for 54,400 litre raceway system (approx AUD$6/wk/m3) Milestone report No.8 | CARD VIE062/04 PROJECT 9 Part 2 Evaluation of contribution of floating raceway technology to the development of marine finfish farming in Vietnam 1. TARGET BENEFICIARIES The primary target beneficiaries in Vietnam include: • Fish farmers who conduct either fingerling or grow-out productions of marine fish • Prawn farmers those want to use their exisiting pond infrastructure to nurse or grow marine fish • The local marine fish farming industry as a whole 2. DEMONSTRATED BENEFITS 2.1 System comparisons and cost analysis 2.1.1 Advantages of using floating raceways Vietnam is developing mariculture with focus on both crustaceans (penaeid prawns, mud crabs and spiny rock lobsters) and marine finfish (barramundi, groupers, cobia, etc.). For fingerling production conventional nursing systems include concrete tanks, earthern ponds or small sea cages. The disadvantages of these systems for fingerling production of marine finfish can be summarized as shown in Table 1 and interestingly all can be well addressed by the use of floating raceways. Table 1: Disadvantages of conventional systems for fingerling production of marine finfish in Vietnam are well addressed by floating raceway technology Systems Disadvantages Floating raceway Concrete tank • High investment cost • High operation cost • Low stocking density • Limited in nursing area • Less expensive, more mobile • Lower operation cost • Very high stocking density • Less limitation with area Earthern pond • Difficult for management (feed, health, grading and harvest) • Large variation of fish size • Low stocking density • Low control of predation and fish health • Highly effective in management (feed, health, grading, harvest) • Lower as grading is easy • Very high stocking density • Full control over predation and fish health Sea cage • Not possible for small • Can even adopt fish at smaller Milestone report No.8 | CARD VIE062/04 PROJECT 10 fingerlings newly discharged from hatcheries • Low control over predation and fish health sizes compared with the normally discharged from hatcheries • Full control over predation and fish health The only two disadvantages of floating raceways, given the development context of Vietnam, include its power-driven operation and relatively high investment cost for poor farmers. Anyway, it is not expected that every farm should have its own floating raceway system, but a group of farms. This way the costs can be shared among the partners and resources are utilized efficiently. 2.1.2 Economic analysis The advantage of using floating raceways for advanced nursing of marine finfish fingerlings was also demonstrated in terms of economic gains in comparison to the two possible conventional nursing systems, i.e. concrete tank and earthern pond. Sea cage is not considered as this system is not suitable for nursing small fingerlings and experience in Vietnam so far has shown mass mortality in advanced nursing of different species of marine fish when sea cage was used as nursing facility. For comparison purpose, SMART-2 floating raceway is used. Table 2: Capital and operation costs for a three-unit SMART-2 floating raceway system. All costs are valid for early 2008. Items Unit cost (mil VND) Cost (mil VND) CAPITAL COSTS 03 SMART-2 floating raceways 22 66 Two air-blowers (second-handed) 4 8 Pipes, electrical accessories 4 4 3 years rent of a coastal reservoir pond (5,000 m2) 15 45 TOTAL OPERATION COSTS for barramundi (1.5-month crop) (mil VND) (mil VND) 120,000 small fingerlings (2 cm total length) 120 Feed (INVE and GROBEST) 10 Electricity 2 3 2 workers 2 6 Consumables and others 10 System depreciation (for 36 months)*1.5 months 3.2 5.1 TOTAL 154.1 Milestone report No.8 | CARD VIE062/04 PROJECT 11 OPERATION COSTS for groupers (1.5-month crop) (mil VND) (mil VND) 60,000 small fingerlings (4-5 cm total length) 360 Feed (INVE and GROBEST) 15 Electricity 2 3 2 workers 2 6 Consumables and others 10 System depreciation (for 36 months)*1.5 months 3.2 5.1 TOTAL 399.1 OPERATION COSTS for cobia (1.5-month crop) (mil VND) (mil VND) 45,000 small fingerlings (4-5 cm total length) 220 Feed (INVE and GROBEST) 15 Electricity 2 3 2 workers 2 6 Consumables and others 10 System depreciation (for 36 months)*1.5 months 3.2 5.1 TOTAL 259.1 PRODUCTION COST (VND/fish) Barramundi Grouper Cobia Survival (%) No. of fish Prod. cost No. of fish Prod. cost No. of fish Prod. cost 50 60,000 2,568 30,000 13,303 22,500 11,516 60 72,000 2,140 36,000 11,086 27,000 9,596 70 84,000 1,835 42,000 9,502 31,500 8,225 75 90,000 1,712 45,000 8,869 33,750 7,677 80 96,000 1,605 48,000 8,315 36,000 7,197 85 102,000 1,511 51,000 7,825 38,250 6,774 90 108,000 1,427 54,000 7,391 40,500 6,398 95 114,000 1,352 57,000 7,002 42,750 6,061 The likely survival after 40 – 45 days of advanced nursing is 70% for barramundi, 90% for groupers and 60% for cobia. If this level of performance is achieved, the floating raceways can compete with any other nursing system including the two conventional ones (concrete tank and Milestone report No.8 | CARD VIE062/04 PROJECT 12 earthern pond) as production cost is far lower than market price (Table 3). Higher survivals can be achieved if management protocol (water quality control, grading, feeding, health care, etc.) is strictly followed and the quality of the purchased fingerlings is excellent. Table 3: Size and prices f