Asia, Vol. 10, No. 1, pp.1-50, January - March 2005

Item Type monograph

Publisher Network of Aquaculture Centres in Asia-Pacific

Download date 03/10/2021 22:39:37

Link to Item http://hdl.handle.net/1834/18132 ISSN 0859-600X Volume X No. 1 January-March 2005

Marine finfish nutrition

Grouper grow-out feeds

Silver pomfret culture

Best practice in using trash Remembering TVR "Ramu" Pillay

Now available on CD-ROM! Freshwater fish biodiversity Aquaculture Asia Volume X No. 1 ISSN 0859-600X is an autonomous publication January-March 2005 that gives people in developing countries a voice. The views and Lessons in organizational action from a natural force opinions expressed herein are those of the contributors and The Dec 26 Indian Ocean tsunami, while causing a lot of misery, may also have do not represent the policies or turned up better ways of looking at and approaching development work in coastal position of NACA. communities that might yet lead to improvements in the state of fi sheries and brighter long-term prospects for fi shers and fi sh farmers. CONSRN partners (BOBP-IGO, FAO Regional Offi ce in Asia, NACA, SEAFDEC and the WorldFish Editor Centre) are working with governments, NGOs and community organizations to Simon Wilkinson assure that there is no disconnect between international actions and local aspira- [email protected] tions. Having worked with governments, community organizations, and members of the civil society, as well as victims of the disaster - in assessing the needs and planning for rehabilitation - we have learned a few lessons to guide us through the Editorial Consultant long and diffi cult recovery and reconstruction period: Pedro Bueno 1. We have been part of many village-level, national and regional activities that leave no doubt that community organizations, NGOs and governments - while they may not all have the tools and may not know everything - know exactly NACA what they want. This happily makes it less complicated for technical organiza- An intergovernmental tions such as CONSRN partners to organize and mobilize technical and donor organization that promotes assistance without complicating our own task by too much debate and philoso- rural development through phising. Listening, rather than talking to governments, civil society and victims sustainable aquaculture. NACA may also avoid the pitfall of patronizing them with a well-intentioned assist- seeks to improve rural income, ance they do not need or that may exacerbate pre-tsunami problems such as increase food production and overcapacity. foreign exchange earnings and 2. It has been amazing to see the peoples’ resilience. Without waiting for exter- to diversify farm production. The nal aid – the fi shers, fi shfarmers and housewives have begun to rebuild their ultimate benefi ciaries of NACA homes, boats and fi sh cages, revive their paralysed economic and organisational activities are farmers and rural systems, and try to get back to normal life. This adds more proof to history’s communities. accounts of how beleaguered peoples can rise above extreme penury with hope, inner strength and resourcefulness rather than with a lot of aid. The simple les- son here is to approach rehabilitation with a good dose of humility. In practical Contact terms, it should be aimed at helping communities help themselves. The Editor, Aquaculture Asia 3. Working with those who are familiar with the local terrain gives one a PO Box 1040 better understanding of what it takes to do proper work. “Terrain” is the minds Kasetsart Post Offi ce and circumstances of the people. The technical expertise from organizations Bangkok 10903, Thailand would be better applied using a map of the terrain drawn by the grassroots Tel +66-2 561 1728 workers rather than us going in to draw new strange looking maps. In practical Fax +66-2 561 1727 terms, the application of international technical assistance would be better Email directed if strategies were developed for specifi c areas and with the [email protected] communities. Website http://www.enaca.org 4. The twin side of destruction is not reconstruction. It is salvation. It is not wrong to spend a lot of money and effort to rebuild what has been destroyed; but it is not right to do so without sparing thoughts and efforts for the more diffi cult battle of enabling communities to save themselves not only from more violence from a capricious nature but from the more insidious agents of despoliation, Printed by abetted sometimes by legal oversight, and sometimes by the wrong policy. Scand-Media Co., Ltd. Pedro Bueno.

1 In this issue

Sustainable Aquaculture

Freshwater prawn culture in China and its market prospects 5 Miao Weimin Page 5 Peter Edwards writes on rural aquaculture: 9 Demise of wastewater-fed duckweed-based aquaculture in Bangladesh

Freshwater fi nfi sh biodiversity – an Asian perspective I: Current status 11 Thuy T.T. Nguyen & Sena S. De Silva

People in Aquaculture

The STREAM Column 18 Page 20 Her farm is destroyed, how can we help? 20 By S.Y. Sim.

Women oyster vendors in Eastern Thailand 21 Brian Szuster and Mark Flaherty

Asia-Pacifi c Marine Finfi sh Aquaculture Network

Feed and feeding practices at farm level for marine fi nfi sh aquaculture in Asia-Pacifi c 25 Sih Yang Sim and Kevin Williams Page 21

ACIAR grouper grow-out feeds program and related CSIRO research 29 Kevin C. Williams, David M. Smith, Ian H. Williams, Simon J. Irvin and Margaret Barclay

Feed development and application for juvenile grouper 34 Ketut Suwirya and Nyoman Adiasmara Giri

Present status in the development of culture technology for the silver pomfret 36 Pampus argenteus Page 37 Sulaiman M. Almatar and Charles M. James

Best practices for using trash fi sh in the culture of juvenile Malabar grouper, 40 Epinephelus malabaricus Le Anh Tuan

Grouper grow-out feeds research at Maros Research Institute for Coastal Aquaculture, 42 South Sulawesi, Indonesia Usman, Rachmansyah, Asda Laining, Taufi k Ahmad Page 43

News & events 47

2 Aquaculture Asia Magazine Notes from the Publisher

Remembering TVR “Ramu” Pillay

(1921-2005)

FAO, where he served with remarkable Development. The core of the strat- distinction, he set several milestones egy was technical cooperation among for aquaculture. The fi rst was the 1966 developing countries. It was a strategy regional conference on warm water that aligned with FAO’s mandate and aquaculture that was probably the fore- UNDP’s advocacy. runner to the 1976 Kyoto Conference The Kyoto Strategy was the product on Aquaculture. Besides organizing and of a series of regional meetings and a technically backstopping innumerable global conference that FAO carried out national and regional projects on aqua- with UNDP support. Ramu Pillay was culture development he also had a hand charged with the planning, oversight A passion for his work and a fi ne taste in initiating the collection of reliable and running of the African, Asian and in wine. statistics on aquaculture production. Latin American regional workshops With the growth of capture fi sheries (held in Accra, Bangkok and Caracas In they call them stalwarts, peo- levelling off in the early 70s, despite during 1975) and the Kyoto Conference ple like Ramu Pillay. It is shorthand for improvements in fi shing gear and fi sh in May 1976. The Strategy conceived an otherwise lengthy list of descriptions fi nding technologies (a worrying com- of a global network of regional aqua- like tall stature, strength of charac- bination even then), Ramu Pillay saw culture centres established in Africa ter and far vision, and a long list of an urgent need for a concerted effort to (ARAC), Asia (NACA), Latin America achievements. He would have been de- accelerate the development of aquacul- (CERLA) and a regional programme in scribed a stalwart had he only worked ture to meet the increasing demand for the Mediterranean (MEDRAP). Each in India. He would have been recog- fi sh and fi shery products. However, fi sh regional centre and programme essen- nized as the father of modern aquacul- farming was in the main a traditional tially comprised national institutions of ture had he chosen to apply his energy, practice, at best an art, and generally excellence, or a network of such institu- passion and wisdom only within Asia regarded as a poor cousin to capture tions for applied research and technolo- where 90 percent of the world’s farmed fi sheries. It did not even fi gure in most gy development, training and exchange fi sh is now produced. But still 30 years governments’ economic development of information. A fi fth centre, the Fish before the previous millennium ended, plans, and where it did, there were not Culture Research Institute in Hungary, when the best available record of global enough support especially in terms of or HAKI, by then strengthened through aquaculture production was 3.5 million scientifi c and technological resources. previous UNDP/FAO assistance, was tons, he saw that the world needed to Aquaculture was so diverse that the later identifi ed to provide these regional farm more fi sh, farm it scientifi cally, proposed mechanism to deal with its centres with support in key disciplines and farm it cleanly. That was vision. research and development needs, which including pond design and engineering. How he sought to turn much of it into was to set up an international research HAKI’s becoming a part of the global reality is the story of how modern centre, was seen as inadequate. Ramu network owes much to Ramu Pillay’s aquaculture evolved. Pillay saw in this situation the oppor- foresight. Hungary was one of the fi rst Ramu blazed an outstanding career tunity to focus global attention on the European countries assisted by FAO in fi sheries and aquaculture research new sector and design a novel arrange- for aquaculture development. Once long before he moved into the sphere ment to address its diversity, lift it rich in fi sheries resources, a century of of international aquaculture develop- from obscurity in national and regional tampering with its rivers and wetlands ment. He authored more than a hundred plans, and move it from a traditional led to its near total reliance on farming research papers many of them seminal practice to a science-based food pro- for fi sh supply. Ramu Pillay foresaw and continue to be cited by researchers duction sector. a similar global process in Hungary’s the world over. Beyond doing research, That broad vision of a global or- transition, during the 1970s, from he felt a greater need in its systematic ganizational arrangement crystallized capture to culture fi sheries. HAKI pio- and practical application. While in into the Kyoto Strategy for Aquaculture neered the transfer of highly productive

January-March 2005 3 nized much earlier, in 1976, when he was awarded an honorary life member- ship by the World Aquaculture Society. He maintained a close relationship with NACA and was appointed honor- ary adviser by its Governing Council in In 1988, as a 1995, helping to guide it to become the member of a model that a number of recent net- NACA team that work development efforts have found visited the Wuxi worthy to emulate (such as the recently integrated fi sh founded Network of Aquaculture Cen- farms and Yellow tres in Central and Eastern Europe, or Sea mariculture. NACEE, and the one being developed in the Americas, the putative NACtA). scientists, technologists, farmers and At that late stage in his career, he government planners, assisted by the sparked the second of his two most ADCP Team. This infused the global important contributions to world aquac- programme elements of national and ulture: The Conference on Aquaculture regional priorities relevant to local in the Third Millennium in Bangkok in problems and needs. This and TCDC 2000, designed as the sequel to Kyoto. became the operating guidelines of the He worked with NACA to write the regional networks, probably exempli- Conference prospectus and develop fi ed best by the Asia-Pacifi c network, its agenda, and then headed a multi- 1991, Relaxing after the NACA NACA, which established itself as agency committee to steer it to com- Governing Council meeting with then an inter-governmental organization pletion. The chairman of the Bangkok DDG of Thai Fisheries, Mrs Bung-orn in January 1990. Two of fi ve is a fair Conference summed up Ramu’s role in Saisithi. record but Ramu Pillay might have it by acknowledging that he “provided done more to improve on it had he not the spark, vision and encouragement” retired in 1985. Nonetheless, the efforts for all participants to join the Confer- Asian fi sh farming practices to Europe. put into developing their programmes ence. He was thus the architect of the With guidance from Ramu and its and staff enabled the others to develop Kyoto Declaration on Aquaculture and scientifi c advisory board, it grew into into centres of excellence and continue the prime mover of events that led to an international research, development rendering useful research and develop- the Bangkok Declaration and Strategy and training centre that served well, ment services to their regions. for Aquaculture Development Be- through the global network, the needs Retirement from FAO did not mean yond 2000, two of the most important of developed but especially developing retirement from aquaculture. Ramu milestones in the development of world countries. Pillay became Director of the Svanoy aquaculture. Guided by the Bangkok To coordinate and develop this Foundation for Aquaculture Develop- Declaration, NACA included in its pro- global network, UNDP supported the ment, Norway, from which he chan- gramme of work for the fi rst fi ve years establishment in FAO of the project, nelled private sector contributions for of the new millennium what Ramu Pil- Aquaculture Development and Coor- aquaculture development in develop- lay had envisaged in 1976: inter-region- dination Programme (ADCP) and put ing countries. When this phase ended al cooperation in accelerating and ex- Ramu Pillay in charge. As Programme as well he resumed writing books. panding aquaculture development. This Leader, he proceeded to translate the Besides the earlier publications (Plan- has made inter-regional cooperation Kyoto Strategy into a global action ning of Aquaculture Development and an important part of the organization’s programme. He recruited and welded Advances in Aquaculture) his other programme, and has found concrete a multidisciplinary team of scientists books are: Aquaculture Principles and examples in many of NACA’s joint and mustered their expertise to develop Practices, 1990; Aquaculture and the projects with institutions and countries regional system-oriented programmes Environment, 1992; and Aquaculture in other regions including the South Pa- of research, training and information Development: Progress and Prospects, cifi c, the Americas, Africa and Europe, that were carried out by the regional 1994. These have become standard some in direct partnership, others in aquaculture centres. The centres were texts for students and practitioners and consortia with international organiza- identifi ed through consultations with been translated into several languages. tions. The latest of these is sadly born governments and strengthened, with Most retirees would have kept to of a catastrophe, but he would have investments from governments, UNDP writing. Ramu Pillay stayed active in been proud to see that the regional and and other donors to become top calibre aquaculture. He lectured, advised the international organizations, to which he institutions of research and develop- Government of India, wrote and gave had given his touch and legacy in vari- ment. The regional programmes were numerous keynote papers at technical ous forms and degrees, rapidly formed developed for implementation with conferences. His contributions to world a consortium to collectively respond to full participation of national teams of aquaculture development were recog- the restoration and development needs

4 Aquaculture Asia Magazine Sustainable aquaculture Freshwater prawn culture in China and its market prospects

Miao Weimin

Freshwater Fisheries Research Centre, CAFS, No. 9 East Shanshui Road, Wuxi, 214081 China.

Development and present “From Kyoto to Bangkok” at the status Conference on Aquaculture in the Third Millennium, February 2000. Freshwater prawns are among the most recently introduced to of the communities devastated by the aquaculture production in freshwater Indian Ocean tsunami. environments in China, despite the tra- Ramu Pillay made aquaculture his ditional preference of the people to the raison d’etre, his life. But his infl uence product in many areas of the country. on its development had not been like Real commercial culture of freshwater the spawning of a sudden wave of inter- prawns did not start until the 1990s al- Macrobrachium nipponensis. est and action. It was, as with his life, a though its experimental culture was re- deliberate, systematic and progressive ported as early as late 1970s. However, process, more like stemming from a freshwater prawn culture has achieved headwaters of vision, given momentum very fast development since the early by perseverance and doggedness, gain- 1990s. Such development is attrib- ing volume and gathering substance uted to several factors; the traditional from the confl uence of numerous preference of Chinese to shrimp and tributaries of interests and objectives as prawn; the rapid decline in the produc- they fl ow along, and eventually branch- tion of marine shrimp culture caused Macrobrachium rosenbergii. ing out into several streams and rivulets by disease problems in the early 1990s; of purposes, each carving its course and increasing demand for high quality and nourishing the developmental products resulting from the improving landscape as it fl ows on to the sea. The living standard of the Chinese people as active career of Ramu Pillay in fi sheries a result of economic development. and aquaculture research and develop- The rapid increase in production of ment may be recorded in fi nite terms as cultured freshwater prawn is the result Penaeus vannamei. 58 years, from 1947 to 2005. But the of expansion in the area, improved river fl ows on. culture techniques and diversifi cation ter prawn in China, reached more than His passing is a great loss to his of cultured species. There is no national 133,000 ha in Jiangsu province, the family. The aquaculture community statistical data available on the total most important region for freshwater share their grief and wish them comfort culture area of freshwater prawn at the prawn culture in China in 2001 (Ge Xi- in their bereavement. He worked until moment. However, freshwater prawn anping, 2002). It accounted for 22.51% his time came up, having just fi nished culture has expanded very quickly of the total inland aquaculture area of the second revision of his book “Aqua- across the country. For instance, Mac- 592,413 ha (Chinese Fisheries Statistic culture Principles and Practices.” It was robrachium rosenbergii was cultured in Year Book 2001) of the province in the as if he did not want the world aquac- only 12 provinces of China in 1993 and same year. ulture community to feel the loss of his there was just one province with pro- The fast expansion of culture area going away. duction more than 1,000 tons. By 2002, and improvement in culture technique Stalwarts are never lost to the world; culture of M. rosenbergii had expanded has resulted in rapid growth in produc- they live on in their legacy. Ramu, we to 25 provinces and autonomous re- tion. Currently, there is no aggregated thank you for the legacy. gions in China. There were eight prov- national statistical data for freshwater Friends of TVR “Ramu” Pillay, 9 inces with the production over 1,000 prawn species available in China. February 2005. tons in 2001. In some areas, freshwater Production of M. rosenbergii during prawn culture is now an important 1993 to 2001 (Figure 1) is a very good component of freshwater aquaculture. example. China is now the largest For example, the total culture area of producer of cultured M. rosenbergii in Macrobrachium nipponensis, one most the world, representing 69% of global important species of cultured freshwa- cultured M. rosenbergii output in

January-March 2005 5 Sustainable aquaculture

Figure 1. Cultured production of M. rosenbergii in China 1993-2001. South Pacifi c Ocean. It was fi rst intro- duced to China for culture in seawater. It was then very recently introduced for culture in freshwater in China. Due to its fast growth rate, longer breed- ing and growth period (compared with M. rosenbergii), the culture of this shrimp in freshwater has expanded very quickly in the last few years and it has become another important freshwa- ter cultured prawn/shrimp species in China. In 2001, production of Pe- naeus vannamei from freshwater pond reached 40,000 tons in Guangdong province, the most important area for Figure 2. Production growth of cultured M. rosenbergii and whole freshwater culture of shrimp in China, inland aquaculture in China during 1996-2001. with the area under culture reaching 8,000 ha. In 2000 the production and culture area were respectively 4,000 tons and 1,000 ha only. Presently, pro- duction of Penaeus vannamei cultured in freshwater has exceeded the produc- tion of Macrobrachium rosenbergii in China. It now contributes signifi cantly to shrimp exports.

Culture Methods

Currently, earthen ponds are the basic culture method commonly adopted for all species of prawn / shrimp cultured 2001. During 1995-2001, an average rosenbergii and M. nipponensis are cur- in freshwater in China. The practice for annual production growth of 31.19% rently cultured on a large scale. different species may differ accord- was attained in M. rosenbergii culture. M. rosenbergii is an exotic species ing to the biological characteristics of In comparison, the average annual in China. The species was cultured in a each species. For stocking, both brood production growth was only 9.27% for very limited area in the Southern China prawn or post larvae of M. nipponensis the whole freshwater aquaculture sector with very small production for more can be stocked in growout ponds. For during the same period (Figure 2). than a decade after it was fi rst intro- M. rosenbergii and Penaeus vanna- Production of another cultured duced in 1976. The fast development mei, post larvae can only be stocked freshwater prawn species; M. nip- of culture of the species started only for growout after acclimatization in ponensis was estimated to be around since the early 1990s. Now, it is one of freshwater. A single crop used to be the 120,000 tons in China 2001, close to two major freshwater prawns cultured dominant practice for the culture of all the capture production of the species. In in China. species before. Aiming to raise the unit 2001, the total production of cultured Another real freshwater prawn spe- production, prolong marketing season freshwater prawn was estimated to be cies widely cultured in China now is and eventually raise the economic over 250,000 metric tons in China, not M. nipponensis, an indigenous spe- effi ciency, multi-crop (2-4 crops/year) including the production of Penaeus cies that can naturally reproduce in all and rotating culture of M. rosenber- vannamei cultured in freshwater envi- kinds of freshwater bodies. Therefore, gii and M. nipponensis has become ronment. Aquaculture is now the major traditional production of the spe- increasingly popular in southern China. source of freshwater prawn in China. cies was mainly from wild fi sheries. Such a change has effectively raised the Although the earliest culture practice unit production from originally 1.5-3.0 Species and culture of the prawn was reported in the 1970s, ton/ha to presently around 5-6 ton/ha methods commercial production started at more (M. rosenbergii and P. vannamei). The or less the same time as M. rosenbergii. improvement in the unit production is Cultured Species Currently, cultured production of this very important to maintain the mini- prawn accounts for about 50% of total mum benefi t in compensating for the Although, freshwater prawn culture production of the prawn in China. reduced market price. attained a very high growth rate in Penaeus vannamei is actually a Culture in rice paddy is another China during the past decade, only two marine shrimp species originally from method commonly adopted in the species of real freshwater prawn, M. South American countries along the culture of M. rosenbergii and M. nip-

6 Aquaculture Asia Magazine Sustainable aquaculture ponensis. Usually only one crop of that have potential to enter international of prawn culture have declined signifi - prawn is produced a year. With a much- market. Freshwater cultured prawn is cantly although the price of the seed reduced stocking rate (M. rosenbergii more likely to take a share in the inter- has also fallen. This has mainly been and M. nipponensis), 300-450 kg/ha of national market compared to fi nfi sh. compensated for through the increase prawn can be produced through supple- In 2002, China exported 108,000 tons in unit production. M. nipponensis mentary feeding and good management of cultured shrimp. This increased by used to maintain a fairly stable market in addition to the normal rice produc- 66% compared with the previous year. price. However, great market pres- tion. This is a very effective approach Production of cultured prawn/shrimp sure has arisen due to the fast growth to improve the economic return of from freshwater, especially Penaeus of production in 2001, resulting in traditional rice cultivation. It also has vannamei comprised signifi cant portion signifi cant declines in the price of the very sound environmental effect due of the export. prawn. Penaeus vannamei has faced a to much reduced pesticides and other On the other hand, Chinese tra- similar situation. The market price for chemicals. ditional agriculture is facing strong the shrimp was fl uctuating around US$ Apart from above mentioned two challenges from the global market since 2.5-4/kg during most of the harvesting culture methods, cage culture and China entered the WTO. Mainly limited season. The farm gate price of Penaeus indoor running water culture are also by small-scale operations, the products vannamei dropped as low as US$ 1.5/ practiced for M. rosenbergii and M. of many traditional farmed crops strug- kg at one point in 2002, a historical low nipponensis in some areas of the gle to compete in the international mar- in Guangdong province. country. However, they are far less ket. To confront such a challenge, the The marketing problems can be popular than pond culture and rice- Chinese government is deepening the largely attributed to several factors. With paddy culture. Their contribution to the structural reform to traditional agricul- M. rosenbergii and Penaeus vannamei total cultured prawn production is very ture. One of the government’s strategies problems are mainly related to the limited. is to develop the aquaculture industry. production and marketing pattern. Due Meanwhile, structural adjustment is to the requirement for high temperature Market prospects also underway within the aquaculture and the season of seed production, the sector for long-term and marketing period for these products is Prospect sound economic benefi t. Priority is be- fairly short. As the production increases, ing given to the culture of those species it naturally causes the market price to Development of culture of freshwater have good market potential and high decline. Disordered competition among prawn and other high valued aquatic economic return rather than ordinary the prawn/shrimp farmer is another im- animals is one of the priority options species such as carps whose market portant factor causing unbelievably low for local government in many parts of is close to saturated. Development of market price of cultured prawn/shrimp the country to replace the cultivation of freshwater prawn culture is in line with in peak harvesting season. some traditional crops with very low such rural development policy. For M. nipponensis, the market pres- economic effi ciency and has been prov- sure and reduced economic effi ciency en to be very effective in past years. Current problems of culture are mainly due to two fac- Although freshwater prawn cul- tors. One is the very fast growth in the ture is now facing some problems and Falling price and declining production without much expansion constraints, the industry is very likely economic return of the market. The other factor is the re- to expand further in the future. This duced market size of the prawn, which prediction is based on the two major Rapid development of freshwater signifi cantly affects the selling price. factors. First, the potential new market prawn culture has been stimulated by The drastic drop in price has caused for freshwater prawn is huge. Domesti- the increasing market demand and high signifi cant decline in the economic cally, freshwater prawns are very much economic return from production. M. return of freshwater prawn/shrimp preferred aquatic products for Chinese rosenbergii used to fetch a market price culture in China during the last few consumers, not only because of high of US$ 6.0/kg very easily several years years. Compared with the general high nutritional value and great taste, but ago. The market price of M. nippon- economic return several years ago, also due to convenience in prepara- ensis could reach US$ 15.0/kg or even the profi tability of freshwater prawn/ tion. Presently, freshwater prawn higher during the Chinese New Year shrimp culture is highly dependant on production is estimated to be around period. However, the rapid growth in the management and production level. 400,000 tons (including the wild catch), production resulting from the expan- The profi t from the culture is usually which account for less 1% of the total sion of prawn culture has already had around US$ 2,000/ha in China. Some fi sheries production in China. Per signifi cant impacts on the market price farmers may even lose capital due to capita availability of freshwater prawn and economic returns of the culture inexperience, poor management and products is less than 0.3 kg. With the industry. low production. improving living standard, there will The market price of M. rosenbergii be a very large room for the domestic has currently dropped to only around demand to increase. China has already US$ 2.5-3.0/kg during the major entered WTO. Aquaculture products are harvesting season, almost half of considered most competitive products previous levels. The economic benefi ts

January-March 2005 7 Sustainable aquaculture

Uneven distribution of Appropriate development Improvement of culture production strategy technique

For all the species, uneven distribu- Appropriate development strategies Freshwater prawn culture is a relatively tion of production is another factor that should be developed and implemented new aquaculture practice in China. causes downward pressure on market with regard to the present status of There have been very limited studies price. For example, M. rosenbergii freshwater prawn culture in different on the culture technology of different production from Guangdong, Jiangsu, parts of the country. Different develop- prawn species in different environ- Shanghai, Anhui and Zhejiang prov- ment targets and priorities should be ments. Present practice is mainly based inces accounted for 91.55% (117,494 set for different areas. For instance, in on the farmer trials and the experience tons out 128,338 tons) in 2001. Chinese the provinces where freshwater prawn of other countries. There is a lot room consumers prefer live prawn, which culture has already developed to certain for the improvement in feed and feed- usually fetches a much high price than level development targets and priorities ing, stocking and culture management. the dead ones. Transportation of large should be the improvement of product These kinds of improvement are par- quantities of live freshwater prawn quality to increase their competitive- ticularly important to delivering sound over long distance is relatively more ness in the international market. These economic benefi ts given the current diffi cult. This results in great pres- provinces are mostly areas with rela- much-reduced market price of the prod- sure on the local and nearby markets tively easy access to foreign markets. ucts. Another important goal is how to during peak harvesting season in these In areas where freshwater prawn ensure the high quality of the products areas. Another factor is that processing culture is still at an early stage prior- throughout the whole culture and mar- technology for freshwater prawn is far ity should be given to expansion of the keting process. Ecological culture that behind the production in China. industry and increasing the produc- minimizes use of various chemicals tion. The target should be to develop and drugs needs to be studied to ensure Increasing pressure in the the local market and contribute to the safe products that are accepted in the international market economic development and income of international market. rural people. Despite the signifi cant growth of Improvement in marketing and cultured shrimp export in recent years, Establishment of quality seed processing export of cultured shrimp is now facing production system market barriers from the major im- The long-term sustainability of the porting countries. The issue of chlo- Quality of prawn seed is now a very freshwater prawn culture industry will romycetin residue signifi cantly struck important factor affecting the produc- ultimately be determined by the eco- the export of China’s export of cul- tion and economic effi ciency of culture. nomic performance of the industry. To tured shrimp to Europe in 2001-2002. It also has signifi cant implications for maintain a reasonable economic benefi t Recently the “anti-dumping” action of long-term development of the industry. it is vitally important to the further the the United States against most Asian It is extremely important to establish development of the industry. Develop- shrimp exporting countries (includ- an effective system for production and ment of effective marketing strategies ing China) is likely adversely impact distribution of high quality prawn seed. and modifi cation of culture systems to the shrimp exports of China. It is very Scientifi c research work needs to be allow longer harvesting and market- likely that shrimp importing countries carried out on the genetic improve- ing periods is particularly important to will undertake similar actions more ment of cultured prawn species. Prawn relieve market pressure that may result frequently to protect their own shrimp breeding techniques should also be from further expansion of the industry. culture industries in the future. developed for the purpose to maintain New culture practices such as multi- the genetic quality of species at produc- crop production and rotating culture Strategies for future tion level. have been proven to be effective in this development In order to maintain the quality of aspect, but they need further refi nement. prawn seed in production, a certifi ca- Processing technology for fresh- It is vitally important to effectively tion system needs to be developed and water aquatic products has long been tackle the existing problems and im- implemented for prawn hatcheries. lagging behind the development of plement an appropriate development Health certifi cation and inspection culture. This is due to both consumers’ strategy for future sustainable develop- mechanisms also need to be established habit and limited efforts on technology ment and sound economic benefi t of the for the trans-boundary movement of development. However, appropriate freshwater prawn/shrimp culture indus- prawn brood stock and seed within and processing technology can reduce the try in China. The following are among beyond the country. This will also ben- marketing pressure in the peak harvest- the priority strategies and measures. efi t the export of cultured shrimp/prawn ing and improve the acceptability to the in the future. international market. Therefore, there is a real need to invest money and human resource to develop suitable process- ing technology for freshwater prawn as well as other cultured animals.

8 Aquaculture Asia Magazine Sustainable aquaculture

Demise of wastewater-fed duckweed- Peter Edwards is a consultant, part based aquaculture in Bangladesh time Editor and Asian Regional Coordinator for CABI’s Aquaculture Compendium, and Emeritus Professor at the Asian Institute of Technology where he founded the aquaculture program. He has nearly 30 years experience in aquaculture in the Asian region. Email: [email protected].

Serpentine duckweed pond on the Agriculture Training Institute (ATI) campus, A duckweed feeding square in a fi sh Khulna. Bamboo reduces the impact of wind which otherwise blows duckweed to pond at the Shobujbagh duckweed the pond margin. , Khulna.

In this column I continue with recent • Crude protein production up to 10 duckweed-based, wastewater treatment developments in, or perhaps ‘demise times greater than that of soybean, and reuse through fi sh culture over the of’ is a more appropriate way to phrase the most productive terrestrial pro- past 15 years. Two systems have been it, wastewater-fed aquaculture. In tein crop. developed: A system fed with conven- my column in the last issue (Octo- • A high crude protein content of 25- tional wastewater or sewage for peri-ur- ber-December 2004, Vol. IX, No. 4), 45% on a dry matter basis. ban areas; and a village level sanitation observations on the constraints facing • A dry matter productivity of 10-40 system with latrines connected to small wastewater-fed aquaculture in Hanoi tonnes dry matter / ha / year. derelict ponds to treat nightsoil and were presented. This column outlines • Ability to grow in shallow water and cultivate duckweed. wastewater treatment and reuse involv- shade. The fi rst duckweed conventional ing duckweed and fi sh in Bangladesh. • Readily harvested by pole and net. wastewater treatment system, which Cultivation of duckweed using Unfortunately there are constraints: still operates, was built in 1989 at Mir- various organic fertilizers is traditional • Growth adversely affected by both zapur, Tangail district. A 0.2 ha anaero- Chinese practice to produce small-size low and high temperature and high bic pond precedes the 0.7 ha duckweed green fodder for grass carp fi ngerlings light intensity. covered pond which was constructed as still unable to consume coarse grass. • Occasional infestation. a 500 m long serpentine channel with However, there has been a tremendous • Rapid decomposition following a hydraulic retention time of about 20 amount of research over the last three harvest. days. About 1,000 m3 sewage / day are decades on various aspects of duck- • Economically diffi cult to dry, espe- treated to such a high degree that the weeds, including their cultivation in cially during rain which prevents effl uent could be used for unrestricted wastewater and subsequent use to feed solar drying. irrigation of vegetables according to herbivorous fi sh. Duckweeds have The NGO PRISM in Bangladesh has WHO standards for wastewater reuse. many positive characteristics: carried out a R & D programme with Duckweed harvested daily is fed to fi sh

January-March 2005 9 Sustainable aquaculture

in three adjacent fi sh ponds of 0.2 ha weed although most continue to culture In reality there is no shortage of each. About 10-15 tonnes of mainly fi sh but with other inputs. Polyculture land as plenty is held, especially by fi ve carps are produced each year although of carps has taken off since the rural bodies: Municipalities, Post and Tele- probably only half the yield is based on sanitation project was implemented and graph, Railways, Roads and Highways, duckweed as rice bran and oil cake are farmers concentrate on more profi table and Water and Power Development fed to fi sh also. The net return accord- fi sh culture without duckweed-based Board. As the opportunity cost of karst ing to Mohammed Ikramullah, Chair- nightsoil treatment. (government) land has risen so much, man of PRISM, is 5-10% annually, According to Mr. Ikramullah, the there is pressure for other uses, legal including land lease and 5 year facility single biggest constraint to the sustain- and illegal. Land speculation is the big- depreciation. PRISM has demonstrated ability of duckweed-based wastewater gest business in Bangladesh. Although that it is possible for a duckweed-based treatment and reuse is the availability land availability is the biggest issue, wastewater treatment system incorpo- of land for what is essentially a land- other major constraints are complex rating fi sh culture to not only achieve intensive system. The PRISM concept and include multiple ownership of land, cost recovery but to derive a net profi t. for duckweed was based on use of availability of working capital, and the Despite having demonstrated the marginal and unutilized, fallow land. rapid rate of infrastructure develop- economic feasibility of low-cost, duck- Earlier studies had reported that there ment, which often results in water bod- weed-based wastewater treatment and were 250,000 ha of low-lying land in ies being fi lled in. Duckweed wastewa- reuse, Mr. Ikramullah expressed major Bangladesh which could be used for ter treatment is not attractive enough to reservations about further dissemina- natural collection, treatment and reuse gain full government support. tion of the technology in Bangladesh. of wastewater. However, the opportu- With so many constraining factors, The local government in Khulna, nity cost of land has gone up rapidly in it is diffi cult to end on a positive note. the third largest city in Bangladesh, Bangladesh, the most densely popu- Perhaps duckweed wastewater treat- provided 0.6 ha of land for a duck- lated country in the world, excluding ment could become an integral part of weed-based system at Sonagandha. The city-states. green belts required to make the peri- community-based project involving urban areas of rapidly expanding cities active participation of an adjacent slum socially as well as environmentally community was funded by UNCDF sustainable? but was destroyed only 3 years later to build a stadium for female athletes. UNDP under the Sustainable Envi- ronmental Management Programme (SEMP) provided funds to build four duckweed pilot in Khulna but suffi cient land could be found to build only two plants. Plants built on leased land on the campus of the Agricul- ture Training Institute in 2000 and at Shobujbagh on private land bought by PRISM in 2003 are also currently in Harvesting operation. However, it is unlikely that duckweed with land will become available to build ad- a scoop net on ditional duckweed-based plants either the ATI campus, in Khulna, where there are 37 large Khulna. sewage outlets in the city, or elsewhere in Bangladesh. The UNCDF funded project Rural Enterprises with Fishermen provided credit to construct 1,500 rural duck- weed-based units in villages. As there was no conventional wastewater in rural villages, latrines were constructed around derelict or unused ponds. The latrines consisted of a moulded concrete slab connected to a pipe that conveyed nightsoil directly to the duck- Harvested weed pond but inside a retaining basket duckweed being made of woven bamboo slats. Harvest- transported to ed duckweed was fed to fi sh in nearby an adjacent fi sh ponds. Mr. Ikramullah informed me pond on the ATI that fewer than 20% still grow duck- campus, Khulna.

10 Aquaculture Asia Magazine Sustainable aquaculture

Freshwater fi nfi sh biodiversity – an Asian perspective I: Current status

Thuy T.T. Nguyen1, Sena S De Silva2*

1. Network of Aquaculture Centres in Asia-Pacifi c, PO Box 1040, Kasetsart Post Offi ce, Bangkok 10903, Thailand; 2. School of Ecology & Environment, Deakin University, PO Box 423, Deakin University, Warrnambool, Victoria, Australia 3280.

This article is based on a manuscript the marine sector in food fi sh pro- food (Welcomme and Bartley 1998; De that has been accepted for publication duction and the consequent fi shing Silva 2003). However, if these trends in the journal Biodiversity and pressures on the marine stocks. Most are to be sustained it is imperative that Conservation authored by Thuy T.T. freshwater fi sheries, particularly those there needs to be a concerted attempt to Nguyen and Sena S De Silva in the Asian region, are artisanal, and maintain biodiversity and have appro- The overwhelming acceptance of fi shing pressures per se are not thought priate conservation measures in place the Brundtland Report, “Our Com- to be a major culprit affecting biodi- for maintaining environmental integrity mon Future’ in 1987 (UNEP 1987) by versity, except in very rare instances, and fi sh stocks. the world community, freshened the but other developments taking place in There have been only a few stud- general thinking on biodiversity and watersheds are (Coates et al. 2003). ies on fi nfi sh biodiversity on a broad, conservation initiatives and related Global fi sh consumption and pro- regional basis in respect of Asia issues and these became an integral duction have witnessed marked chang- (Kottelat and Whitten 1996). In an era part of all development. Subsequent es since the early 1970s; there has been where there is likely to be an upsurge follow-up global consultations lead to a shift towards increased consumption in inland fi shery activities, including the establishment of the Convention of fi sh in the developing world, which aquaculture, in most developing nations on Biological Diversity (CBD) in 1994 also dominates production with around in Asia, and the fact that freshwater (CBD 1994), which currently provides 70% of global output (Delgado et al. fi shes are purported to be the most leadership with regards to global biodi- 2003). Inland fi sh accounts for about threatened group of food source versity issues and initiatives. 20-25% of the animal protein intake, for humans (Bruton 1995), it is op- Biodiversity is variously defi ned. particularly in rural populations in portune to evaluate the present status of In essence, biodiversity refers to the the developing world (Delgado et al. fi nfi sh biodiversity in the region. Here, abundance and the variety within and 2003). Consequently, there is an in- emphasis is laid on East, South and among fl ora and fauna, as well as the creasing emphasis on the development Southeast Asia in view of the greater ecosystems and ecological processes of inland fi sheries as a signifi cant con- inland water resources and fi nfi sh to which they belong, and is usually tributor in narrowing the growing gap diversity compared to North, West and considered at ecosystem, species and between supply and demand for fi sh Central Asia (IUCN classifi cation). genetic levels (Kottelat and Whitten 1996). Biodiversity initiatives, by and Figure 1. Average total and per-capita water availability in different large, have tended to be more focussed continents (based on data from Shiklomanov, 1998). on terrestrial ecosystems, particularly in the past. Until recently, and when aquatic systems were targeted the emphasis generally was more on coral reefs and wetlands, but only marginally on freshwater per se. While less than Cubic km/ yr Cubic m/ yr (x1000) 0.01% of the world’s water resources occur as surface waters these are home 16000 100 13510 82.2 to a very high level of biodiversity, sup- 12030 80 ported through a number of freshwater 12000 ecosystems: Rivers, lacustrine waters, 7890 60 marshes, and seasonal or ephemeral 8000 38.2 wetlands. Almost 25% of global ver- 40 4050 tebrate diversity is accounted for by 4000 2900 17.4 2360 20 fi sh and a signifi cant proportion of it 4.23 5.72 3.92 is concentrated in this meagre 0.01% 0 0 of earth’s freshwaters. However, most Total availability (cubic km/ yr) emphasis on fi sh biodiversity issues Asia Africa Europe N & C Per capita availability (cubic m x 1000/yr) have tended to be on marine species, America Oceania S.America perhaps because of the importance of Australia &

January-March 2005 11 Sustainable aquaculture

Asian inland water Figure 2. The regression on ln land area (km2) on ln species in Asian resources nations/ regions provided in the database of Kottelat and Whitten (1996). The numbers refer to the corresponding number in table 1 and The earth is estimated to have only the broken line represents the 95% confi dence limits. 3 35,029,000 km of freshwater, repre- senting 2.5% of all water resources and 9 of which only 23.5% is habitable, the Ln species = 0.384 Ln area + 0.651 rest being ice caps and glaciers (Shiklo- 8 R2 = 0.628 1 2 manov 1993; Smith 1998). Asia has the 7 P < 0.001 4 3 most inland water resources amongst 5 6 6 10 7 8 all continents (Shiklomanov 1993, 1 9 11 13 14 1998), even though the amount avail- 5 16 17 15 able on a per capita basis is relatively 23 18 Ln Species Ln 4 24 20 22 21 low (Figure 1). Asia has a number of 19 very large river systems, such as the 3

Brahamputra, Ganges, Irrawaddy, In- 2 dus, Kapuas, Mekong, Pearl, Yangtze, Yellow and Red, amongst others, most 1 of them fl owing through a number of 6 7 8 9 10 11 12 13 14 15 16 17 nations. The bulk of these rivers fl ow Ln Area through the tropical and the sub-tropi- cal regions, enhancing the potential There is a paucity of natural lakes in created through reservoir construction, diversity of the fi sh fauna (Oberdorff et Asia compared to most other conti- primarily in the second half of the last al. 1995). Adding to main river habitats nents, these being mostly found in the century in Asia is the highest amongst are the fl ood plains, interconnected active volcanic regions of South East all continents, but these tend to have a streams, rapids and headwaters which Asia, such as in Indonesia and the much lower diversity than the original all provide unique features that add to Philippines (Fernando, 1980). On the stretch of the dammed river/ stream, potential diversity. other hand, the lacustrine water habitats and will be dealt with in a later article. Suffi ce is to state that river impound- ment / dam construction is rather a Table 1. The land area (km2), number of fi nfi sh species recorded controversial issue with serious politi- and the ratio of the number of fi nfi sh to land area x 1000 in selected cal and socio-economic repercussions nations/ regions of Asia. and of global concern (McCully, 1995; Roy, 1999). Country Area (km2) Species no. (Species/Area)103 Apart from the above major fi nfi sh Indonesia 1,944,000 1,300 0.7 habitats others of importance are black China 9.560,948 1,010 0.1 water streams, marshes and swamps, India 3,387,593 750 0.2 and caves and aquifers. The fi sh fauna Thailand 513,517 690 1.3 of some of these habitats has been little Vietnam 329,566 450 1.4 studied until recently, and their impor- Borneo 535,830 440 0.8 tance from a biodiversity point of view Philippines 299,404 330 1.1 is just beginning to be unravelled. For 462,000 329 0.2 example, the peat swamps of peninsular Sumatra 475,300 300 0.6 Malaysia are reported to contain 10% Malay peninsular 131,235 300 2.3 of all the fi sh species of the peninsular Myanmar 676,581 300 0.4 (Ng 1994). Laos 236,798 262 1.1 Bangladesh 144,054 260 1.8 Asian fi sh fauna Cambodia 181,035 215 1.2 803,941 159 0.9 The number of recognised fi nfi sh Java 132,570 130 1.0 species in the world is estimated to Nepal 147,181 129 0.9 be around 25,000 (updated to 28,100; Taiwan 36,179 95 2.6 http://www.redlist.org/info/tables/ta- Sri Lanka 65,610 90 1.4 ble1.html) and of these about 10,000 Korean peninsular 99,143 90 0.7 are found in freshwater, and another Irian Jaya 414,800 80 0.2 160 species require freshwater, at one Sulawesi 186,140 70 0.4 stage or another, to complete their life Brunei 5,765 55 9.9 cycle (Nelson 1976). However, these Singapore 618 45 72.9 numbers are not static, as new species Data from Kottelat and Whitten, 1996; Mongolia has been omitted. are often recorded from the region,

12 Aquaculture Asia Magazine Sustainable aquaculture and as the of some others is Of the Asian rivers the Mekong tio*1000) was signifi cantly correlated sorted out. is the richest in fi sh fauna with 37 to the ln basin area for the major river According to Kottelat and Whitten families and 450 recorded species, but systems (Figure 3), the relationship (1996) East, South and Southeast Asian currently it is estimated that the number being: nations have a cumulative total of a of fi nfi sh species in the Mekong could freshwater fi nfi sh fauna of 7,447 spe- actually be as high as 1,200 (CBD ln (species richness index) = - 0.789 ln cies, with Indonesia having the largest 2003; Coates et al. 2003). The fi n- (area) + 9.368 (R2= 0.748; P< 0.001) number of 1,300. It is also important fi sh faunal diversity of 21 major river to note that the fi sh fauna in most na- basins in East, and South and Southeast The above relationship however, differs tions, except perhaps Singapore and Sri Asian nations (table 2) indicates that from that derived by Welcomme (2000) Lanka, two relatively small island na- species diversity is not necessarily for African rivers, where the relation- tions, is not fully documented. Table 1 related to familial diversity. The Ir- ship was based on data transformed gives the species richness and the land rawaddy basin has the highest known into log10. Based on the above regres- area and the ratio of these parameters familial diversity with 34 families but sion relationship the species richness in selected nations/regions in Asia. It is has only 79 species, as opposed to the index was estimated for each of the evident that Singapore ranks highest in Mekong basin, which is poorer in fa- river systems (Table 2) and it is evident this regard with a ratio of 72.9. The ln milial diversity but very rich in species that the rank order changes dramati- of fi nfi sh (freshwater) species number diversity. Bhat (2003) documented the cally compared to the estimates of that to land area ratio was signifi cantly diversity and composition of freshwater of the World Conservation Monitoring correlated to the ln of the land area, the fi shes in river systems in the Central Centre. This analysis demonstrates that relationship (fi gure 2) being: Western Ghats, India, and found that fi sh species richness is not necessar- there was 25% endemicity amongst a ily correlated to river basin size, and ln (species ratio) = ln 0.384 (land species richness of 92. In general, there indeed in the region, rivers with small area in km2) + 0.651 (R2 = 0.628; P< is a paucity of studies of fi nfi sh biodi- basins such as the Cauvery (India/Ne- 0.001). versity in Asian rivers. Dudgeon (1992) pal), Kapuas (Indonesia) and Chao attempted to point out that Asian river Phraya (Thailand), have high indices of In general, ecologists and biogeogra- ecosystems are endangered, and the 1.62, 1.53 and 1.32, respectively. phers have long recognized that species main reasons he listed were all related richness increases with area, but at a to human activity, but over fi shing was Status of fi nfi sh decreasing rate (Connor and McCoy, not one of these. He compared the deg- biodiversity 1979; Rosenzweig, 1995; Ovadia, radation of Asian rivers to those of the 2003). The species-area relationship, north-temperate regions, but stressed According to the IUCN Red List (2003) as seen in respect of fi nfi sh species in that the biological understanding on of all life forms 21,067 species are Asia, is non-linear, and the implications Asian rivers was insuffi cient to halt or threatened (includes critically endan- in managing biodiversity “hotspots” limit further degradation. gered, endangered and vulnerable) (Myers, 1988, 1990) have been dis- When the major river systems in the globally, and of these 2,640 (12.5%) are cussed by Ovadia (2003). region were considered as a separate fi nfi sh species (Table 3). In Asia as a In Asia by and large, as elsewhere entity, the ln species richness index whole, 6,106 organisms are threatened in the world, the major diversities in (number of species to basin area ra- of which 688 are fi nfi sh species, and in the fi sh fauna occur in the large river systems and their associated fl oodplains Figure 3. The regression of number of ln of species to basin area (Welcomme 2000; CBD 2003; Coates ratio.1000 to ln of basin area for major river basins (table 2) in East, et al. 2003). The fi sh fauna in East, and South and Southeast Asia. South and Southeast Asia is dominated by cyprinids (about 1,000 species), fol- 2.5 lowed by loaches (about 400 species) y = -0.7898x + 9.3685 of the families Balitoridae and Cobitii- 2 R = 0.7477 dae, gobies of the family Gobiidae (300 1.5 species), catfi shes (about 100 species) P < 0.001 of the family Bagridae and members of 0.5 the Osphronemidae family (85 spe- cies). Most of the fi sh species diversity -0.5 occurs in the tropical area (Kottelat and

Whitten 1996). Lundberg et al. (2000) (Sp/Area*1000) Ln -1.5 noted that in Asia the diversity at the family level (121 families) was consid- erably higher than in African and Latin -2.5 American inland waters, where only 50 9.5 10.5 11.5 12.5 13.5 14.5 and 55 families, respectively have been Ln Area recorded.

January-March 2005 13 Sustainable aquaculture

Table 2. The fi sh faunal characteristics of major river basins that are located in East, South and Southeast Asia. The countries of location of the respective basins are given in parentheses. Species richness @ is calculated in relation to basin area based on a regression derived for river basins world wide, and @@ is based on the regression relationship of the basins given in the table. Data, except @@, from Conservation Monitoring Centre (http://www.unep-wcmc. Orginformation_services/public); @@ based on the regression in Figure 4.

River basin Basin area (km2) No. of fi nfi sh: Species richness Families Species @ @@ Yantze (Ch) 1,711,156 23 320 1.10 0.140 Ganges-Brahamputra 0.209 1,684,918 32 na na (Ban, Bhu, In, Nep) Indus (Afg, Ch, In, Pak) 1,031,425 24 147 0.44 0.236 HwangHo (Ch) 880,881 21 160 0.56 0.254 Mekong (Cam, Ch, La, 450 0.452 804,381 37 1.62 Myan, Tha,Vn) (1200)* Irrawaddy (Ch, In, Myan) 387,631 34 79 0.06 0.634 Godavari (In) 320,937 28 na na 0.640 LiaoHo (Ch) 274,124 17 na na 0.857 Krishna (In) 252,443 29 187 1.02 0.947 Salween (Ch, Myan, Tha) 249,481 34 143 0.76 1.047 SongHong- Red River 1.288 172,462 24 180 1.08 (Ch, Lao, Vn) ChaoPhraya (Tha) 151,868 36 222 1.32 1.315 Mahanadi (In) 149,500 26 na na 1.360 Fly (Indo, Png) 133,687 13 101 0.56 1.415 Kapuas (Indo.) 102,874 32 250 1.53 4.273 Sepik (Indo, Png) 100,243 10 53 -0.02 0.140 Narmada (In) 96,062 26 77 0.37 0.209 Cauvery (In, Nep) 91,375 27 265 1.62 0.236 Ma (La, Vn) 36,550 25 na na 0.254 Ca (La, Vn) 22,975 26 na na 0.452 Pearl (Ch) 22,537 21 106 1.04 0.634 Afg- Afganistan; Ban- Bangladesh; Bhu- Bhutan; Cam- Cambodia; Ch- China;In- India; Indo- Indonesia; La- Laos; Myn- Myanmar; Nep- Nepal; Pak- Pakistan; Png- : Tha- Thailand; Vn- Vietnam * Coates et al. (2003).; but not used in the regression in Figure 4.

Figure 4. The number of threatened fi nfi sh species (of ten or more) territories when considered in relation in each of the in nations in East, South and Southeast Asia, and the to the respective total fi nfi sh fauna is number threatened expressed as a percentage of the total fi nfi sh tantamount to nearly 25% of the fi nfi sh fauna of that nation/ territory (data extracted from http://www.redlist. fauna of Singapore, Sri Lanka and org.info/ tables/table5). Taiwan, all three relatively small island states (Figure 4). On the other hand, in Indonesia 91 fi nfi sh species is under 1400 30 Species threat and accounts for 17.1% of the total fi nfi sh species under threat in the 1200 % threatened 25 region but elsewhere it is less than 10% 1000 20 (Figure 5). 800 In East, and South and South East the Asian region central to this analy-15 Asia 66 species of freshwater fi n- 600 sis (East, South and South East Asia) fi sh are critically endangered and/or the estimate is 4,975 and 462 (9.2%), endangered, that is about 1.3% of all

10 Threatened % Species diversity Species 400 respectively; but it accounts for 17.5% freshwater fi nfi sh species in the region 200 of all fi nfi sh species threatened. 5 (Table 3). The endangered species In the region under consideration, belong to 16 families, of which Family 0 more than ten fi nfi sh species are in0 a accounts for 32 species or d n ia threatenedia statusan in eacha of rtwelvee na- nearly 50% of all endangered species s p wa India ilan i nk po ne China laysia Ja a do ippinestions/territories.Ta TheLa number of threat- (Table 4). Of the 66 critically endan- Tha Ma Vietnamil ri ing In h Cambod S S P ened species in these twelve countries/ gered and/or endangered species more than half (34 species) fall into the

14 Aquaculture Asia Magazine Sustainable aquaculture

Figure 5. The number of threatened fi nfi sh (ten or more) species This article will be followed-up by in nations in East, South and Southeast Asia, and the number one on factors affecting biodiversity threatened expressed as a percentage of the total for the region (data of fi nfi sh in the Asian region in a extracted from http://www.redlist.org.info/ tables/table5). forthcoming issue of this magazine.

References

Bhat, A. 2003. Diversity and composition of freshwater fi shes in river systems of Central Western Ghats, India. Environmental Biology of 68: 25- 38. Bruton, M.N. 1995. Have fi shes had their chips? The dilemma of threatened fi shes. Environmental Biol- ogy of Fishes 43: 1-27. CBD (Convention on Biological Diversity). 1994. Text and annexes. Interim Secretariat for the Convention on Biological Diversity, Chatelaine, Switzerland. 34 pp. CBD (Convention on Biological Diversity). 2003. Status and trends of biodiversity of inland water ecosys- tems. CBD technical Series No.11, 116 pp. Coates, D., Poeu, O., Suntornaratana, U., Tung, N.T., Viravong, S. 2003. Biodiversity and fi sheries in the Lower Mekong Basin. Mekong Development Series No. 2, Mekong River Commission, Phnom Penh, Table 3. Numbers of threatened species of all forms and fi nfi sh 30 pp. species in the different geographic regions. The geographic regions Connor, E.F., McCoy, E.D. 1979. The statistics and biol- are those used in the IUCN Red List and the data are extracted from ogy of the species-area relationship. The American the Red List (2003; http://www.redlist.org/info/tables /table5.html). Naturalist 113, 791-833. De Silva, S.S. 2003. Culture-based fi sheries: an underu- Region Number of threatened species tilized opportunity in aquaculture development. All organisms Finfi sh Aquaculture 221, 221-243. North Africa 201 58 Dudgeon, D. 1992. Endangered ecosystems: a review Sub-Saharan Africa 4076 465 of the conservation status of tropical Asian rivers. Antarctic 26 2 Hydrobiologia 248: 167-191. East Asia 873 119 Fernando, C.H. 1980. The fi shery potential of man-made North Asia 237 38 lakes in Southeast Asia and some strategies for its South & South East Asia 4102 343 optimization. In: BIOTROP Anniversary Publica- West & Central Asia 894 188 tion, BIOTROP, Bogor, Indonesia, pp. 25-38. Europe 1676 366 Haniffa, M.A., Raj, A.J.A., Nagarajan, M., Perumal- Mesoamerica 1410 203 sammy, P., Seetharaman, S., Singh, S.P. 2004. Genes Caribbean Islands 1201 294 and Fish. Natural breeding in captivity- a possibility North America 1165 181 for conservation of threatened freshwater feather- South America 3362 149 back Notopterus notopterus. Aquaculture Asia, IX Oceania 1844 234 (1); 35-38. Total 21067 2640 Kottelat, M., Whitten, T. 1996. Freshwater biodiversity in Asia with special reference to fi sh. World Bank former category. Habitat wise (Table elsewhere. A case in point for exam- Technical paper 343, 59 pp. 4) it is relatively disconcerting that 14 ple is India. In India, Conservation Lundberg, J.G., Kottelat, M., Smith, G.R., Stiassny, endemic species, all cyprinids, in Lake Assessment and Management Plan M.L.G., Gill, A.C. 2000. So many fi shes, so little Lanao, Mindanao, Philippines are criti- has identifi ed 327 freshwater fi shes in time: an overview of recent ichthyological discovery cally endangered, followed by fi ve spe- India to be threatened, of which 45, 91, in continental waters. Annals of the Missouri Bo- cies from fi ve families (Amblycipiti- 81 and 66 to be critically endangered, tanical Garden 87: 26-62. dae, Bagridae, Balitoridae, Cyprinidae, endangered, vulnerable and low risk McCully, P. 1995. Silenced rivers. The ecology and poli- Siluridae) in Dian Chi Lake in China. near threatened, respectively (Haniffa tics of large dams. Zed Books, London, 350 pp. It is also important to point out that et al., 2004), which is obviously sig- Myers, N. 1988. Threatened biotas: hotspots in tropical different nations may have prepare nifi cantly different to that of the IUCN forests. The Environmentalist 8, 178-208. their own list of endangered species, list. However, in the present article, to Myers, N. 1990. The biodiversity challenge: expanded taking in to consideration depletion of retain uniformity, we have adhered to hot-spot analysis. The Environmentalist 10, 243- populations of certain species which the IUCN records, and in a manner this 256. on the other hand remain almost intact also helps to minimises confusion.

January-March 2005 15 Sustainable aquaculture

Nelson, J.S. 1976. Fishes of the World. John Wiley & Rosenzweig, M.L. 1995. Species diversity in space and Smith, D. I. 1998. Water in Australia. Oxford University Sons, London. time. Cambridge University press, UK. Press, Oxford. 384 pp. Ng, P.K.L. 1994. Peat swamp fi shes in Southeast Asia- Shiklomanov, I .A. 1993. World freshwater resources. UNEP 1987. Our Common Future. The World Commis- diversity under threat. Wallaceana 64: 7-9. In: Gleick P.H. (ed), Water in Crisis: A Guide to the sion on Environment and Development, Commis- Oberdorff, T., Guegan, J.-F. and Hugueny, B. 1995. World’s Fresh Water Resources. Oxford University sion for the Future. Geneva, Switzerland. Global patterns of fi sh species richness in rivers. Press, New York, pp. 13- 24. Welcomme, R.L, Bartley, D.M. 1998. Current ap- Ecogeography 18: 345-352. Shiklomanov, I. A. 1998. Archive of world water proaches to the enhancement of fi sheries. Fisheries Ovadia, O. 2002. Ranking hotspots of varying sizes: resources and world water use. Global Water Data Management and Ecology 5: 351-382. a lesson from the nonlinearity of the species-area Files: StateHydrological Institute. Data archive on relationship. Conservation Biology 17, 1440-1444. CD-ROM from State Hydrological Institute, St. Roy, A. 1999. The cost of living. Flamingo, London, Petersburg, Russia. 162 pp.

Table 4. Critically endangered (CR) and endangered (EN) fi nfi sh species, and the English common names, belonging to different families in East and South and Southeast Asia. The known habitats (anadr.- anadromous; br- brackish water; ma- marine; fw- freshwater) together with the distribution of each species is given. Where available the specifi c location of occurrence is given. The table is based on data obtained from the IUCN Red List of Threatened species (http://www.redlist.org/search.php?freetext).

Family / Species Common Name(s) Distribution Habitat Status Acipenseridae Acipenser dabryanus Dabry’s sturgeon Korea and Yangtze Basin, China andr; fw CR Yantze sturgeon A. mikadoi Sakhalin sturgeon Japan and Korea andr; fw; br; ma EN A. chrenckii Amur sturgeon Endemic to the Amur basin, China fw; br EN A. sinensis Chinese sturgeon China, Japan and Korea andr; fw; br; ma EN Huso dauricus Kaluga Amur basin, China fw; br EN Adrianichthyidae kruyti Duck-billed buntingi Indonesia fw CR orthognathus Buntingi Indonesia fw EN Sharp-jawed buntingi Xenopoecilus oophorus Egg-carrying buntingi Indonesia fw EN X. poptae Popta’s buntingi Indonesia fw CR X. sarasinorum Indonesia fw EN Amblycipitidae nigricauda Dian Chi Lake, China fw EN Bagridae medianalis Dian Chi Lake, China fw EN Balitoridae Yunnanilus nigromaculatus Dian Chi Lake, China fw EN Belontiidae Betta livida Peninsular Malaysia fw EN B. miniopinna Indonesia fw CR B. persephone Malaysia fw CR B. spilotogena Indonesia fw CR Parosphromenus harveyi Peninsula Malaysia fw EN Clupeidae Tenualosa thibaudeaui Mekong River Basin fw EN Cobitidae Lepidocephalichthys jonklaasi Spotted loach Sri Lanka fw EN Botia sidthimunki Chao Phraya and Mekong basins fw CR Cyprinidae Acheilognathus elongatus Dian Chi Lake, China fw EN Anabarilius polylepis China. fw EN Balantiocheilos Silver shark Thailand, Malay Peninsula, fw EN melanopterus Indonesia Cephalakompsus pachycheilus Endemic to Lake Lanao, Philippines fw CR

16 Aquaculture Asia Magazine Sustainable aquaculture

Table 4 continued.

Chela caeruleostigmata Mekong and Chao Phraya basins fw CR Cyprinus micristius Dian Chi Lake, China fw EN Danio pathirana Barred danio Nilwala River basin, Sri Lanka fw CR Hampala lopezi Born, Indo-China, Siam, Philippines fw CR Green , Labeo fisheri Mountain labeo Sri Lanka fw EN Mountain labeo Labeo lankae India and Sri Lanka fw CR Mandibularca resinus Bagangan Endemic to Lake Lanao, Philippines fw CR Onychostoma alticorpus Taiwan fw EN Ospatulus palaemophagus Endemic to Lake Lanao, Philippines fw EN O. truncatus Bitungu Endemic to Lake Lanao, Philippines fw CR Probarbus jullieni Julien’s golden carp Chao Phraya and Meklong basins fw; br EN Seven-striped barb Puntius amarus Pait Endemic to Lake Lanao, Philippines fw CR P. asoka Asoka barb Sri Lanka fw EN P. bandula Sri Lanka. fw CR P. baoulan Baolan Endemic to Lake Lanao, Philippines fw CR P. clemensi Bagangan Endemic to Lake Lanao, Philippines fw CR P. disa Disa Endemic to Lake Lanao, Philippines fw CR P.lavifuscus Katapa-tapa Endemic to Lake Lanao, Philippines fw CR P. herrei Endemic to Lake Lanao, Philippines fw CR P. katalo Katalo Endemic to Lake Lanao, Philippines fw CR P. lanaoensis Kandar Endemic to Lake Lanao, Philippines fw CR P. manalak Manalak Endemic to Lake Lanao, Philippines fw CR P. martenstyni Sri Lanka fw EN P. tras Tras Endemic to Lake Lanao, Philippines fw CR Rasbora wilpita Sri Lanka. fw EN Schizothorax lepidothorax China fw EN Spratellicypris palata Palata Endemic to Lake Lanao, Philippines fw CR Tor yunnanensis China fw EN Gobiidae Pandaka pygmaea Dwarf pigmy goby Indonesia, Philippines and fw; br; ma CR Singapore. Weberogobius amadi Poso bungu Indonesia fw CR Melanotaeniidae Chilatherina sentaniensis Sentani rainbowfish Lake Sentani, Indonesia. fw CR Melanotaenia boesemani Boeseman’s Indonesia. fw EN rainbowfish Osteoglossidae Scleropages formosus Asian arowana Indonesia, Malaysia, Thailand, fw EN Asian bonytongue Cambodia and Viet Nam Golden arowana Golden dragonfish Pangasiidae Pangasianodon gigas Mekong giant Endemic to the Mekong basin fw Polyodontidae Psephurus gladius Endemic to the Yangtze River basin, fw CR China Salmonidae Oncorhynchus formosanus Taiwan fw CR O. ishikawai Satsukimasu salmon Japan fw EN Salvelinus japonicus Kirikuchi char Japan fw EN Siluridae Encheloclarias curtisoma Peninsular Malaysia fw CR E. kelioides Peninsular Malaysia, Indonesia fw CR Silurus mento Endemic to Dian Chi Lake, China fw EN

January-March 2005 17 People in aquaculture The STREAM Column

We’ve been debating what a STREAM aquaculture or other natural resource complex situations in people’s lives and column in Aquaculture Asia should management and an understanding con- hint at even more lofty goals like the do. It’s been quite impassioned actu- temporary development issues. They democratization of knowledge. They ally (which is almost certainly a good are good communicators, and in regular immediately raise practical challenges thing!). That’s partly because as a face-to-face and internet contact. They about the structure and functioning of learning and communications initiative, are part of a system linking government institutions to understand and support since November 2001, we have many and non-government colleagues embed- people, especially people with least existing communications vehicles. ded through Partnership Agreements voice and power. Scariest of all, they There is the STREAM Journal shar- into ministries, provincial offi ces, cities tempt us to muddy our hands with ing six short pieces each quarter, from and towns and reaching out to diverse problems and processes that give rise to farmers, fi shers, fi sheries offi cers, spe- networks of people, self-help groups policy development. cialists from many fi elds and building and their federations, supporting them Many readers of Aquaculture Asia links, one to another; our website with to provide ever better services. grapple with the basics and the big- its News and Events feature and Media What began as a general desire ger pictures. If this column provokes Monitoring Service, and the ever-grow- to share messages about processes, debate and thinking about lofty and the ing Virtual Library. There are country technologies, lives and opportunities local goals then we can cease debating pages and documents about ways of amongst farming and fi shing communi- about what this column should do. working: developing country strategies, ties and those who work with them, is planning processes, ways to monitor having to evolve into a system of shar- STREAM Website and evaluate those expected changes ing meaning, currently in 14 languages, www.streaminitiative.org (the ones in Logic Frameworks) and about complex concepts like sustain- the unanticipated changes, told by real able development and livelihoods STREAM Regional Offi ce people in signifi cant change stories. approaches and some of their basic c/o NACA components like foraging from paddies Department of Fisheries Complex A regional network and small water bodies, gleaning from Kasetsart University Campus, Phahol- reaching out to people shores and reefs, fi shing and managing yothin Rd small-scale aquaculture, fi nding oppor- Bangkhen, Bangkok 10903 Thailand From early pilots in Vietnam and tunities and hope. Phone: 662 561 1728/29 Cambodia, STREAM Communications Communications and learning Fax: 662 561 1727 Hubs are currently operated from 11 shared over gulfs of distance, culture, Email: [email protected] countries across Asia-Pacifi c, managers language, social and natural systems are fl uent in English and local lan- and environments are brave yet lofty guages, with a background in fi sheries, aspirations. They ask us to confront

E-mails and other tales…

Working together

Dear HQ Rome, Today I had a talk with STREAM Vietnam and I think we are complete- ly on the same line concerning the fi sheries network for Vietnam and even better, they have done already a great part of the job to establish it. Please fi nd attached the proposal of STREAM Vietnam for a national fi sheries network of June 2004 and give your comments on it. They and I will try to launch the internet site as soon as possible after consulting some other big parties such as OneFish, UNDP, FMIS and NACA.

We are on the right way now!

Regards, Fisheries Specialist Food and Agriculture Organization of the , Hanoi.

18 Aquaculture Asia Magazine People in aquaculture

E-mails and other tales…

Legal use of documents

Dear STREAM Initiative, At your webpage (www.streaminitiative.org) we found in- teresting and valuable documents relevant to our ongoing work. Unfortunately, I couldn’t fi nd any statement about their legal use. We are a Cooperation Programme between the German Technical Cooperation Agency (GTZ) and the Mekong River Commission working in the fi eld of watershed man- agement within a regional policy framework. We kindly request permission to download and store the documents provided on your webpage within our internal system and to post them further at MekongInfo.

Information Management MRC-GTZ Cooperation Programme

Thank you for your enquiry and your positive feedback on our website and your interest in our work. The legal position is as follows: All our publications are Copyright ©The STREAM Initiative, publication year. Reproduction for educational or other non-commercial purposes is authorized without prior permission from the copy- right holder, provided the source is fully acknowledged. Reproduction for sale or other commercial purposes is prohibited without prior permission from the copyright holder. Therefore you are welcome to reproduce our publications on the above basis. We try to log downloads and distribution of our publications and your help in doing this would be appreci- ated. We might also consider linking the two webpages. We could put a link from our Virtual Library to your site and visa versa. Let me know if you are interested to do this.

More tools for sharing meaning and where to get them: Livelihoods CD

Dear STREAM Initiative, I am interested to acquire the CD, A Process and Practice for Understanding the Livelihoods of Fishers and Farmers. How can I get it? Thanks a lot for any kind of information. Yours, Université Montpellier II France.

Dear Montpellier,

Thank you for your message. If you email us your postal address, we will send you a copy of the CD in which you are interested. We invite you to visit our website and E-mails and other tales… library (www.streaminitiative.org).

Dear STREAM Initiative, STREAM E-Bulletin

As always I do appreciate your courtesy and service. I have Dear Colleague found your publications resourceful and informing. Please keep the noble work up. Welcome to the STREAM E-Bulletin, outlining activities and outputs of the STREAM Initiative, which is distributed Sincerely, to a range of stakeholders concerned with aquatic re- Paul Namisi sources management. We invite you to view the E-Bulletin at http://www.streaminitiative.org/Subscribe.html.

January-March 2005 19 People in aquaculture Her farm is destroyed, how can we help? By S.Y. Sim.

The tsunami caused severe damages in six provinces in southern Thailand. Many lives were lost. For many of those who survived life goes on – but in an extremely diffi cult situation. Khun Chew Oi Charuanhatakid is a 65 year old lady who was born and lives in Krabi. She has been farming marine fi sh for more than 20 years. Originally, she invested 600,000 baht from her savings to start up a marine fi sh farm with twenty fl oating cages. She gradually built her farm up and before the tsunami she was running 48 cages of around 3 x 3 x 3 metres, located near Krabi Fishing Port.

After the tsunami: The tangled wreckage of Khun Chew Oi’s cages is visible to the right of the damaged farmhouse, now run aground.

they cannot sell to other places, due to the diffi culty in transporting small quantities of marine fi sh fi ngerlings. When I fi rst met Khun Chew Oi prior to the tsunami, she said “if I don’t buy Khun Chew Oi as I fi rst met her: A from them, they will have no income happy fi sh farming lady in Krabi who and if they do not have money, they liked to help small fi shermen by buying will do bad things”. There were more their catches. than ten fi shers she bought her fi nger- lings from. Khun Chew Oi used to employ Her farm was totally destroyed by Khun Chew Oi paddles back to her casual workers to help with her farming the tsunami. She has nothing left - no farm after sending off visitors. activities such as grading fi sh, buying fi sh, no cages. She cannot do other fi sh feed, cleaning and repairing nets work because of her age and her lack of and harvesting. She lived in a fl oating schooling. She does not have employ- house built on the farm. She used to able skills except for fi sh farming. have two boats, each worth about 6,000 After the tsunami, a fi sheries offi cial baht, one with an engine costing 10,000 visited her farm. He told us that she is baht. She also had a small generator, now using her very last savings to try which cost around 13,000 baht. to put together a very small area to start She bought her marine fi sh fi nger- her farm again. She was in tears, and in lings mainly from small-scale fi shers need of help. who were fi shing in the nearby areas. Although she could buy fi ngerlings Khun Chew Oi feeding her fi sh during from elsewhere she preferred to help a visit conducted under the NACA/ out the small local fi shers, because she Deakin University survey visit in April knew that if she doesn’t buy from them 2004.

20 Aquaculture Asia Magazine People in aquaculture Women oyster vendors in Eastern Thailand

Brian Szuster and Mark Flaherty

Thailand’s seafood industry is a major source of employment for households in many rural and peri-urban coastal communities. Although the wild fi shery continues to account for the largest vol- ume of seafood production in Thailand, and is the largest source of wage labor, aquaculture is playing an increasingly important role in the overall fi sheries sector. Participation in aquaculture is, however, often characterized by a distinct gender division of labor (DFID, 2000; Chaisri, 1997). Men are usu- ally responsible for husbandry while women predominate in post-harvest ac- tivities such as sorting, processing and marketing. Despite the high visibility of women in post-harvest activities, very little research has been undertaken to develop a better of understanding of the specifi c roles that women play in the aquaculture sector. While aquaculture is generally seen as playing an impor- tant role in poverty reduction, little is known about the income that women derive from aquaculture, factors that contributed to their participation in the industry, or issues that limit their in- volvement. Such information would be invaluable in developing training and extension programs that support wom- en’s aquaculture activities and thereby enhance household incomes (Felsing et. Oyster vendor shucking oysters with her son. al., 2000). To date, however, relatively little emphasis has been placed on developing these programs in most 100 kilometers southeast of Bangkok of seafood products sold to domestic Southeast Asian countries (Brugere et. along the Bangpakong river estuary consumers in Thailand. al., 2001; Matics, 1997). The Thailand (Figure 1). This area is an important Aquaculture Management Project, oyster growing area in eastern Thailand Oyster production and which is a collaborative project involv- that is now farmed quite intensively. marketing in Thailand ing faculty from the Department of The research focuses on women oyster Aquatic Sciences at Burapha University vendors who operate small roadside All oysters in Thailand are produced by in Thailand and the Department of Ge- operations adjacent to the oyster grow- aquaculture, and total harvests dur- ography at the University of Victoria in out sites. In addition to information ing the year 2001 were approximately , is currently designing a small about their oyster marketing activities, 20,000 tonnes (Department of Fisher- pilot program to help address this gap. the women were surveyed regarding ies, 2003). Although oysters represent This paper reports the results of a their knowledge of product handling only approximately 16% of Thai- small study undertaken to collect base- and seafood safety issues. This infor- land’s total farmed shellfi sh harvest line data on the involvement of women mation will be used to help develop a by weight (green mussel and blood in oyster vending. The study site targeted extension program that would cockle harvests are much larger) the selected was Ang Sila, a small peri-ur- help women oyster vendors to improve oyster crop was worth more than $20 ban community located approximately their operations and enhance the safety million USD in 2001. Semi-traditional

January-March 2005 21 People in aquaculture

culture techniques are employed and oysters in Thailand. Extending basic typically involve the use of concrete seafood sanitation techniques to this posts or bamboo rafts to support oysters group could enhance the quality and growing within suitable near-shore safety of fresh oysters sold to domestic areas. Fresh shucked oysters are a very consumers, and potentially allow these popular food item in Thailand that is women entrepreneurs to access more commonly sold at roadside stands or in lucrative markets such as Bangkok. local markets. A small proportion of the oyster crop is frozen for sale in areas Background of female more distant from the coast or bottled oyster vendors Oyster harvest, Ang Sila, Thailand. and preserved in brine. The sale of Thai oysters is largely Twenty women oyster vendors in the limited to domestic markets as a result Ang Sila district of Chonburi Prov- of stringent seafood safety regulations ince were interviewed during August in major export markets such as Japan, of 2003. This group represents ap- Europe and the United States (Chaler- proximately 50% of the total number of mwat et. al, 2003). Although Thailand’s female oyster vendors operating in the seafood processors have made signifi - district at that time. The average age of cant improvements in product safety the women was 46 years and 95% were and sanitation in recent years, these married and had children. Education Women oyster shuckers, Ang Sila, advances have been largely restricted levels were modest (averaging Grade Thailand. to large-scale commercial processing 5) with Grade 9 being the highest level plants that supply international mar- of education attained by any of the kets. A far larger number of small-scale women surveyed. All the women lived operations supply seafood such as in the Ang Sila area and 40% had more oysters to the Thai domestic market. than 10 years experience with oyster Unfortunately, these small commercial vending. The balance of the women in enterprises regularly process and mar- the sample had been selling oysters for ket oysters in conditions that have the an average of just over three years. A potential to compromise public health. large percentage of the women (45%) As noted previously, women dominate decided to become oyster vendors be- the small-scale marketing of farmed cause shellfi sh farming and/or market- Above and below: Oyster vendor at her stand, Ang Sila, Thailand. Figure 1: Location of the Study Site.

Preserved bottled oysters and other seafood products.

22 Aquaculture Asia Magazine People in aquaculture

was 100 baht ($2.50 USD) during the survey period, and a bottle of preserved oyster typically sold for $3 USD. Most customers are members of the general public who stop at a favorite roadside stand, but 25% of the vendors indicated that they also sell to local restaurants or food stands. The average vendor sold 30 kilos of fresh oysters per week and had a approximate weekly net income of 2000 baht ($50 USD).

Seafood safety issues

Oyster consumption can potentially produce a number of health concerns related to the presence of pathogenic bacteria, viruses, shellfi sh biotox- ins or chemical contaminates (U.S. FDA, 2001). Fortunately most of the Oyster strings on bamboo racks, Ang Sila, Thailand. phytoplankton blooms in the Gulf of Thailand are not toxic, but pathogenic ing was a traditional activity in their cal farms, and pays approximately 7 bacteria such as Vibrio do exist in family. Other factors that led women to baht ($0.18 USD) per kilo for shell-on oyster growing regions contaminated participate in oyster vending included oysters sold in baskets or sacks. Sub- by sewage (Chalermwat et.al., 2003). good income levels and the nature of stantial spoilage occurs in fresh oysters Outbreaks of viruses such as Hepatitis oyster vending as a fl exible, local job. purchased from local farms, but the A can also occur as a result of consum- The part-time nature of oyster vending women can only determine the extent ing of uncooked contaminated shellfi sh. was particularly important to younger of this loss after shucking. Chemicals in the form of pesticides, women with pre-school aged children. Most of the women shuck their own herbicide or heavy metals are potential- Most of the women (55%) focused on oysters, but many (75%) also employ ly present in coastal waters, and these selling oysters at their own road-side part-time help for this task. Part-time can produce illness if contaminated stand, but other survey participants shuckers are usually a family mem- shellfi sh are consumed by over a longer were also involved in shellfi sh farming ber or a local woman hired by the period of time. or operating a second small food stall oyster vendor on a day-by-day basis. The control of pathogenic bacteria or gift shop. Part-time shuckers typically earn 20 is particularly important in Thailand baht ($0.50 US) per kilo of shucked because fresh, uncooked oysters are Income and marketing oysters, and an experienced person the preferred product form for most information can shuck up to 30 kg. per day. Their domestic consumers. Given this con- potential daily income of $15.00 US cern, the women oyster vendors of Ang Half of the women surveyed obtained for shuckers should be placed in the Sila were surveyed for their level of their oysters from a local family farm context of Thailand’s minimum wage, knowledge related to seafood sanitation that is often operated by their husband. which is 146 baht ($3.65 US) per day and potential health concerns related This pattern matches the division of in Chonburi province (TDRI, 2002). to their oyster processing activities. In labor between men and women found Most of the vendors would like to general, sanitary conditions at the stalls elsewhere in Southeast Asia with re- sell more product, but fresh oysters were poor and fresh oysters were com- spect to aquaculture activities (Chaisri, must be sold within 24 hours of being monly processed in conditions favora- 1997; Spliethoff, 1987). It is notable, shucked and this limits the total daily ble for pathogen growth. Temperature however, that 20% of these women amount of oysters a vendor can process directly participate in oyster farming in each day. Unsold shucked oysters are addition to managing a small roadside typically bottled in fi sh sauce to avoid marketing outlet. In most of these situa- spoilage, and this is the only form of tions a husband and wife team manages preservation practiced by most vendors. the family oyster farm, but a small Bottled oysters are, however, much less number of women operate oyster farms popular than the fresh shucked oysters independently with the assistance of in Thailand. A typical vendor sells hired male laborers to assist with physi- approximately 100 kg. of fresh oysters cally demanding tasks. The average per week and two or three bottles of female vendor obtains approximately preserved oysters. The average retail Oyster farming in the upper Gulf of 200 kg. of oysters per week from lo- price of a kilo of fresh shucked oysters Thailand, Ang Sila area.

January-March 2005 23 People in aquaculture

control is the key factor controlling changing slowly through the action of a regional workshop held at the Asian Institute of the degree of pathogen growth in fresh groups such as the Thai National Wom- Technology. Bangkok, Thailand. May 2-3, 2000. oysters. However, none of the roadside en in Fisheries (TWIF) that provide pp. 14. vendors had access to refrigeration. Ice both organizational and operational Department of Fisheries (2004). Statistics of Marine is used to prevent spoilage of shucked support to women involved in aquacul- Shellfi sh Culture 2001 (No. 1). Ministry of Agricul- oysters, but this form of temperature ture. The Thai Department of Fisheries ture and Cooperatives, Bangkok. control is both limited and variable in has agreed to act as a focal point for Felsing, M., C. Brugere, K. Kusakabe, and G. Kelkar. its ability to limit bacterial pathogen the TWIF, but much more government (2000), Women for aquaculture or aquaculture for growth. Fresh and shucked oysters attention is needed in this area. women? INFOFISH International (3): 34-40 were regularly exposed to temperature Female oyster vendors are keenly Matics, K. .(1997) Women contribution to fi sheries abuse as daytime temperatures typically aware of the limitations associated development in Southeast Asia. In: Women in Fish- rise above 35 degrees C at the roadside with their reliance on fresh-shucked eries in Indo-China Countries. M. Nandeesha and H. stands. The female vendors we inter- oyster sales. Many of the women in Hanglomong (eds.). PADEK, Batit Fisheries Station, viewed had a limited understanding of the survey group expressed a desire Phnom Penh, Cambodia. pp. 11-20. seafood safety issues with only 10% of to learn value-added processing and Spliethoff, P. (1987). Handling, processing, and market- the sample having any formal training preservation techniques. A lack of suit- ing of aquaculture products. In: Women in Aqua- in this area. This training consisted of a able small-scale technologies repre- culture. C. Nash, C. Engle and D. Crosetti (eds.). one-day government-sponsored course sents a major existing constraint for Proceedings of the ADCP/NORAD Workshop on in basic food hygiene techniques devel- most female oyster vendors. A focused Women in Aquaculture. Rome, FAO, 13-16 April oped to improve sanitary conditions in training program would clearly benefi t 1987. restaurants and other food outlets. Nev- women oyster vendors by provid- TDRI. (2002). Thailand Economic Information Kit: ertheless, it is encouraging that most ing them with the skills required to 2002. Thailand Development Research Institute of the vendors (80%) acknowledged process and preserve larger quantities (TDRI). Bangkok, Thailand. their lack of knowledge in this area and of oysters on a daily basis. A lack of U.S. Food & Drug Administration. (2001). Fish and indicated that they would like to have training and extension opportunities has Fisheries Products Hazards and Controls Guidance more information about seafood safety not only limited the growth of oyster (Third Edition). Center for Food Safety & Applied and food hygiene techniques. sales in Thailand, but it has also denied Nutrition. Washington, DC. Thai consumers the health benefi ts Discussion and of seafood sanitation procedures that Authors conclusions are enjoyed by consumers in Europe, Japan and the USA. Fresh oysters are Dr. Brian Szuster is an Assistant Pro- Oyster vending is a fl exible, local form susceptible to contamination from a fessor in the Department of Geography of employment that provides a valuable variety of sources, but many of these at the University of Hawai’i at Manoa source of income for women with mod- hazards can be controlled through ap- (445 Social Sciences Building, 2424 est levels of education in rural and peri- propriate seafood sanitation techniques. Maile Way, Honolulu, HI, USA 96822) urban coastal communities of Thailand. The extension of training programs that Dr. Mark Flaherty is a Professor in Women dominate the processing and focus on women are clearly appropriate the Department of Geography at the marketing of oysters in Thailand, but given the dominance of women in the University of Victoria (PO Box 3050 their training needs have been largely processing and marketing of oysters in STN CSC, Victoria, BC, V8W 3P5, ignored by government agencies that Thailand, and technical support of this Canada) provide aquaculture extension serv- type could play an important role in ices (DIDF, 2000). There are several improving the safety of a seafood that Acknowledgement reasons for this situation. Shellfi sh is highly valued by Thai consumers. aquaculture was not part of the export- This research was supported by the oriented boom in seafood production References Thailand Aquaculture Management that swept Thailand during the past Project (TAMP), which is based at fi fteen years. Most extension services Brugere, C., Kusakabe, K., Kelkar, G., Felsing, M. and Burapha University, Thailand. Funding that developed during this time focused Muir, J. (2001). Women in Aquaculture. Project for TAMP is provided by the Canadian on large commercial plants involved FWG 03/99, Asia Pacifi c Economic Cooperation, International Development Agency in the processing of farmed crops such Singapore. (CIDA) in association with the Univer- as shrimp. Oyster production is almost Chaisri, Y. (1997) Women in fi sheries in Thailand. In: sity of Victoria, Canada. Information completely restricted to small domestic Women in Fisheries in Indo-China Countries. M. in this paper will be used by TAMP to markets in Thailand and is considered Nandeesha and H. Hanglomong (eds.). PADEK, develop training materials for female a relatively insignifi cant generator of Batit Fisheries Station, Phnom Penh, Cambodia. pp. oyster vendors in eastern Thailand. Ole revenue. Part-time seafood processing 126-128. Heggen of the University of Victoria and marketing activities conducted by Chalermwat, K., B. Szuster, and M. Flaherty (2003). prepared maps used in this paper. women also continue to be viewed as Shellfi sh Aquaculture in Thailand. Aquaculture Eco- less socially signifi cant than full-time nomics and Management 7 (3/4), pp. 249 - 261. farming activities undertaken by men Department for International Development. (2000). (Brugere et. al., 2001). This situation is Gender-Responsive Aquaculture Policy. Report of

24 Aquaculture Asia Magazine Marine Finfi sh Aquaculture Network

AAsia-Pacisia-Pacifi c MMarinearine FFininfi shsh AquacultureAquaculture NetworkNetwork MMagazineagazine

Feed and feeding practices at farm level for marine fi nfi sh aquaculture in Asia-Pacifi c

Sih Yang Sim and Kevin Williams January-March 2005 There are many marine fi nfi sh species ity and the farmer’s view that pelleted cultured in the Asia-Pacifi c region and feeds are more expensive. In contrast, Feed and feeding practices many of these still rely on trash fi sh as Australian fi sh farmers exclusively use at farm level for marine the sole food source for nursery and pelleted dry feeds for almost all farmed fi nfi sh aquaculture in Asia- grow-out stages. Although there are fi sh, including barramundi, groupers, Pacifi c: 25 some commercially produced for- snappers and Atlantic salmon. Southern mulated feeds, Asia farmers, particu- blue fi n tuna is the only marine fi nfi sh larly small scale operators, prefer the species in Australia where fresh fi sh ACIAR grouper grow-out traditional methods of feeding trash (usually pilchards) is fed but even this feeds program and related fi sh to carnivorous species such as industry is slowly changing to feeding CSIRO research: 29 snapper, Asian seabass (barramundi) pelleted dry feeds as better tuna formu- and groupers because of its availabil- lations are developed.

Feed development and application for juvenile grouper: 34

Present status in the development of culture technology for the silver pomfret P. argenteus: 36

Best practices for using trash fi sh in the culture of juvenile Malabar grouper, Epinephelus malabaricus: 40

Grouper grow-out feeds research at Maros Research Institute for Coastal Aquaculture, South Sulawesi, Indonesia: 42 Farm worker feeding pelleted feed at a Penang seabass farm.

January-March 2005 25 Marine Finfi sh Aquaculture Network

Marine Finfi sh Aquaculture Magazine An electronic magazine of the Asia-Pacifi c Marine Finfi sh Aquaculture Network

Contact Asia-Pacifi c Marine Finfi sh Aquaculture Network Feeding pelleted feed to threadfi n at a marine fi sh farm in Johor. PO Box 1040 Kasetsart Post Offi ce Malaysia kg, depend on species and season. Bangkok 10903, Thailand However, since trash fi sh contains Tel +66-2 561 1728 (ext 120) Marine fi nfi sh farmers in Malaysia use a lot of water, around 70% or more, Fax +66-2 561 1727 a limited commercial formulated feed. whereas pelleted dry feed contains only Email [email protected] Most carnivorous species are cultured about 10% water, the pelleted feed is Website http://www.enaca.org/ on trash fi sh although several carnivo- less expensive than trash fi sh when the marinefi sh rous and omnivorous species (eg. Lates comparison is made on the basis of the calcarifer Asian seabass, Eleuthonema amount of nutrients each provides. Cost Editors tetradectylum fourfi ngers threadfi n is only one factor to consider as some Sih Yang Sim and Trachinotus blochii pompano) use fi sh do not readily take to pelleted feed Asia-Pacifi c Marine Finfi sh generic Asian seabass feed as the main unless they have been weaned onto it Aquaculture Network feed source, supplemented with trash from an early age. c/o NACA fi sh. Snapper and grouper species are Most humpback groupers (Cromi- [email protected] mostly fed with trash fi sh. This is often leptes altivelis) are fed on pelleted of poor quality and consists of a mix- Dr Michael J. Phillips ture of unwanted fi sh species, usually Environmental Specialist & very small in size. Manager of R&D, NACA However, other marine fi nfi sh [email protected] species such as milkfi sh are fed with industrial bakery rejects or low-grade Simon Wilkinson wheat fl ours. The growth rate of these Communications Manager fi sh is very slow, requiring a total of 18 [email protected] months for 1 cm fry to reach a market- able size of around 300-500 grams. Dr Mike Rimmer Principal Fisheries Biologist Indonesia (Mariculture & Stock Enhancement) The farming practice in Indonesia is DPIF, Northern Fisheries Centre a mixture of feeding pelleted dry feed PO Box 5396 produced by commercial feed com- Cairns QLD 4870 panies, or trash fi sh. Although com- Australia mercial feed for grouper is available in [email protected] Indonesia, the price is still high, about Farm worker feeding formulated feed US$1/kg. By comparison, the cost of to pompano fi ngerlings at a fl oating trash fi sh is about US$ 0.35-0.59 per cage farm in Johor.

26 Aquaculture Asia Magazine Marine Finfi sh Aquaculture Network

Farm worker cleaning fresh sardine, headed, gutted and de-boned for feeding to groupers. Trash fi sh cut into different sizes to suit dry feeds while other grouper species Hong Kong and China various sizes of groupers in different (Epinephelus spp and Plectropomus cages. spp.) are mostly fed on trash fi sh. In Hong Kong most cultured marine Normally, commercial feed is broad- fi nfi sh species are carnivorous with US$ 0.20-0.25 per kg. Other species cast into the cages and the fi sh fed to species including seabreams, snap- such as tiger grouper (Epinephelus apparent satiety based on the judgment pers, amberjack, cobia and pompano. fuscoguttatus), tongue soles (Cynoglos- of the workers. Trash fi sh is usually Most farms are still feeding trash fi sh sus spp.) and fl ounders (Pseudorhom- chopped into pieces according to the but some farms use dry pellets, with a bus spp.) are mostly fed with farm size of groupers. Some farmers will few using moist pellets for grow-out made moist feed, with local trash fi sh remove the head and gut before feeding practices. as the main ingredient and mixed with to the grouper, while others who are Several species of marine fi nfi sh fi shmeal. When the supply of trash fi sh running on a larger scale simply cut the farmed in the southern part of China are is scarce, particularly during closed whole fi sh into chunk-size pieces, gut fed mostly on trash fi sh, particularly for fi shery season, formulated dry feed is included. aggressive feeders such as amberjack used as a supplement. Dry feed costs The species of trash fi sh used varies and cobia. Fresh trash fi sh cost around around US$0.85/kg. from place to place and the time of the year. Most of the trash fi sh used in Indonesia is of good quality.

Thailand

Formulated pelleted dry feed is used for most seabass farming in Thailand. However, for other carnivorous species such as grouper, snapper and trevally most farmers still prefer to use trash fi sh. The quality of trash fi sh is gener- ally quite good, with a price of around US$ 0.20-0.28 per kg depending on season and species. Currently, there is no commercial feed available locally for snapper or groupers.

Farmer feeding trash fi sh to groupers in Southern Thailand.

January-March 2005 27 Marine Finfi sh Aquaculture Network

Vietnam

Vietnam farms a wide range of marine carnivorous fi nfi sh species including snappers, seabreams, groupers and cobia. Most of the feeding is based on trash fi sh particularly in farming areas at Cat Ba Island and Halong Bay. The trash fi sh cost around US$ 0.19-0.45/ kg. Most of the trash fi sh are freshly caught by small-scale fi shers and deliv- ered to the farms by boat daily.

Australia

The main marine species cultured in Australia are southern bluefi n tuna (Thunnus maccoyii), Atlantic salmon Trash fi sh and fi shmeal mixed to form a “block” of moist feed for nursery of fi ve (Salmo salar), Asian seabass/barra- centimeter grouper fi ngerlings. mundi (Lates calcarifer) and yellowtail king fi sh (Seriola lalandi). There is also some production of snapper (Pagrus auratus), groupers (E. coioides), mul- loway (Argyrosomus hololepidotus) and black bream (Acanthopagrus butcheri). All marine fi nfi sh farming in Aus- tralia uses extruded pelleted dry feed except for southern bluefi n tuna where a transition is occurring from feeding fresh pilchards to extruded pellets. Depending on the species, these feeds are produced as slow-sinking pellets (for most seacage farms) or as a fl oat- ing pellet. Floating pellets are used for aggressive feeders such as yellowtail king fi sh and especially for barramundi cultured in freshwater impoundments where the turbidity of the water encour- ages the fi sh to feed at the surface. Atlantic salmon, southern bluefi n tuna and yellowtail king fi sh are cultured in Milkfi sh feeding on industrial bakery rejects. large polar cages of 80 m diameter or bigger while barramundi are cultured in rectangular or polar cages of varying sizes. Smaller and typically rectan- gular cages (lengths of 4 to 6 m) are used for fi sh cultured in freshwater impoundments while larger rectangular or polar cages (lengths or diameters of 20+ m) are used for fi sh in seawater. Atlantic salmon and barramundi feeds are formulated specifi cally for these species while these or slight variants of them are used for the other species. Barramundi feeds typically contain 45-50% crude protein and 13 to 18% lipid and cost from US$1.10 to 1.20 per kg. Atlantic salmon feeds are 40-42% crude protein and 28-30% lipid, costing Typical polar cages used for Atlantic salmon culture in Tasmania. from US$1.30 to 1.45/kg.

28 Aquaculture Asia Magazine Marine Finfi sh Aquaculture Network

ACIAR grouper grow-out feeds program and related CSIRO research

Kevin C. Williams1, David M. Smith1, Ian H. Williams2, Simon J. Irvin1 and Margaret Barclay1

1 CSIRO Marine Laboratory, PO Box 120, Cleveland, Qld. 4163, Australia, Email: kevin. [email protected] 2 Animal Biology, Faculty of Natural Feeding commercial slow sinking feed to groupers in Lampung. and Agricultural Sciences, University of Western Australia, 35 Stirling Highway, WA, 6009, Australia.

Groupers are highly prized fi sh in the live reef fi sh markets of Hong Kong and other Asian cities where prices (US$/kg) range from 8-11/kg for gold spot grouper (Epinephelus coioides), $15-20 for tiger grouper (E. fuscogut- tatus), $30-40 for coral trout (Plec- tropomus spp) and red grouper (E. akaara) and $80-95 for mouse grouper (Cromileptes altivelis). The recent de- velopment of technology for large-scale hatchery production of grouper fry in Indonesia and the Philippines, largely as a result of research carried out in the collaborative ACIAR grouper project, is producing a plentiful supply of grouper fi ngerlings for aquaculture on- growing. At the time that the ACIAR Farm workers are feeding trash fi sh to cobia in Cat Ba Island. grouper project began in 1999, infor- mation on the nutritional requirements of groupers for grow-out from fry to market was almost non-existent. To address this need, the ACIAR grouper project collaborators in Australia, Indonesia, the Philippines and Vietnam embarked on grow-out feeds research with the primary aim of developing cost-effective pelleted grouper grow- out feeds. Our approach was to: 1. Defi ne the requirements of groupers for the key nutrients that determine the rate at which fi sh grow. 2. Determine the nutritive value of lo- Sea cages used at Marine Harvest’s Tiwi Island (near Darwin) barramundi farm, cally available marine and terrestrial which produces about 1,500 tonnes of fi sh per year. Problems with crocodile and feed ingredients; and shark predation has been overcome using stainless steel mesh.

January-March 2005 29 Marine Finfi sh Aquaculture Network

3. Examine the extent to which high cost marine protein feed ingredients could be replaced using cheaper and more renewable terrestrial protein feed ingredients. The ultimate goal is to develop pelleted grouper feeds as a more sustainable, lower-polluting and cost-effective al- ternative to the feeding of fresh fi shery bycatch. If achieved, this would pro- vide a more sustainable and profi table way of culturing groupers and at the same time reduce competition between man and aquaculture for a dwindling supply of fi shery catch and lessen aquaculture’s impact on the surround- ing environment. This article details the project re- search carried out by CSIRO and sum- marizes other grow-out feeds research Flow-through constant temperature seawater experimental array consisting in the ACIAR grouper project. Other of 48 x 100 L insulated tanks at CSIRO used for grouper nutrition research. articles in this series describe in more detail the project work that was carried gerlings. Additional metabolic studies ing the higher lipid diet did bring about out in Indonesia and Vietnam. were undertaken to see if feeding lipids some sparing of protein for energy. comprised mostly of medium chain A second comparative slaughter growth ACIAR Grouper Project fatty acids (12-14 carbon chain length) assay and digestibility experiment grow-out feeds team would stimulate the fi sh to better use employing the same culture conditions lipid as an energy source and so spare as for the fi rst experiment was carried The research was a collaborative effort or reduce the amount of protein needed out to see if supplying lipid at moderate between four laboratories that were for- in the diet. Key fi ndings of the research (15% added oil) or high (30% added mal participants in the ACIAR Grouper are outlined below. oil) concentrations in the diet and in the project and a fi fth institution, which be- form of either long-chain fatty acids came affi liated with the project through Optimal dietary protein and lipid (LCFA, as olive oil) or medium-chain a complementary Australian AusAID content fatty acids (MCFA, as coconut oil) af- CARD project. The collaborating fected the way the fi sh used the lipid as institutions and team leaders were: An 8-week comparative slaughter an energy source. Five diets, a low-lip- Dr Kevin Williams, CSIRO Marine growth assay and digestibility study id (6%), high-protein (76% CP) control Research, Cleveland, Australia; Dr N. involving 10 pelleted dry feeds and diet and four ‘lipid’ diets that made up Adiasmara Giri, Research Institute for 4 replicate tanks of fi sh per treatment a 2 x 2 factorial of the two types and Mariculture, Gondol, Bali, Indonesia; (10 g start weight) was carried out to two concentrations of lipid, were fed Ms Asda Laining, Research Institute determine the optimal dietary crude to six replicate tanks of fi sh (300 fi sh for Coastal Aquaculture, Maros, South protein (CP) and lipid specifi cations for in total; 14 g average initial weight) Sulawesi, Indonesia; Dr Oseni Mil- juvenile mouse grouper. Fish growth for 8 weeks. The formulation of the lamena, South East Asian Fisheries rate, food conversion ratio, nutrient ‘lipid’ diets was identical to the control Development Centre, Tigbuaan, Ilioli, retention and protein digestibility of the except that the required amount of lipid the Philippines; and Dr Nguyen Dinh diet improved linearly as the amount of was included at the expense of defatted Mao, University of Fisheries, Nha CP in the diet was increased from 38 to fi shmeal with a concomitant lowering Trang, Vietnam. 59%. However, increasing the amount of the dietary CP from 76 (control diet) of lipid in the diet from 14 to 22% to 64 and 53% for the 15 and 30% lipid CSIRO studies on protein reduced energy digestibility but growth treatments, respectively. and lipid utilization in mouse rate of the fi sh was unaffected. Fish fed Increasing the amount of lipid in groupers C. altivelis the higher lipid diets were much fatter the control diet by adding 15% of olive (Table 1). oil (LCFA) at the expense of fi shmeal A series of growth assay and digest- As the digestible protein (as N) con- resulted in a 14 to 20% improvement in ibility studies were carried out un- tent of the diet increased, the amount of growth rate and food conversion, a dou- der controlled laboratory conditions digestible N required per kg fi sh weight bling of the body fat content of the fi sh (fi ltered fl ow-through seawater at 29ºC gain increased: linearly for the 14% li- (from 15 to 29% DM) and the retention and 12:12 photoperiod) to determine pid diets, and curvilinearly for the 22% of dietary protein was increased by the optimum dietary protein and lipid lipid diets (Figure 1). This shows feed- 28% (from 25 to 32%). Higher addition specifi cation for mouse grouper fi n- of olive oil (30%) reduced voluntary

30 Aquaculture Asia Magazine Marine Finfi sh Aquaculture Network food intake by 40%, and consequently depressed growth rate by 32% while protein retention and body fat content were unchanged. Adding coconut oil (MCFA) instead of olive oil depressed food intake by 59%, with a similar re- duction in growth rate and no increase in protein retention. The amount of dietary lipid retained as body fat in the fi sh relative to that oxidized for energy decreased with increasing dietary lipid and was less for MCFA than for LCFA lipids (Fig. 2).

Metabolism of fatty acids

The ‘lipid’ diets fed in the aforemen- tioned Experiment 2 were used in this study except that radioactively-labeled fatty acids were incorporated to allow the metabolism of these fatty acids to be traced. As a marker for MCFA, 14C- octanoic acid (an 8 carbon chain fatty acid) was used while 14C-oleic acid (an 18 carbon chain fatty acid) and 14C- palmitic acid (a 16 carbon chain fatty acid) were used as markers of LCFA. Diets with these labeled fatty acids were fed to fi sh in metabolic chambers (7-9 replicates per treatment) and the amount and rate of lipid oxidation quantitatively determined by measure- ment of the 14C label present in the fi sh, in the expired CO2 and in the dissolved and particulate organic matter in the water of the metabolic chamber. The lipid in the MCFA diets, ir- respective of whether present at 15 or 30% of the diet, was oxidized far more rapidly than the LCFA lipid, with far more of the 14C label appearing in the respired CO2 and less remaining in the fi sh (Table 2). The amount of lipid in Laboratory Technician Leigh Whitlock Laboratory carrying out lipid analyses at the diet appeared to have no effect on CSIRO’s Cleveland laboratory. the amount of lipid oxidized. Moreover, respiration rates increased dramati- • Increasing the lipid content of the Other grow-out feeds research in cally when fi sh were fed the MCFA diet above about 15% did not pro- the ACIAR Grouper Project compared to the LCFA diets, indicating mote greater fi sh growth but rather a physiological response of the fi sh to led to increased body fat deposition Digestibility of feed ingredients remove CO2 produced as a result of and a reduction in food intake. There lipid oxidation (Figure 2). was some evidence of protein spar- The apparent digestibility of a compre- ing by dietary lipid. hensive range of ingredients available Conclusions • Replacement of LCFA lipids (such in the Philippines and Indonesia was as fi sh or long-chain vegetable oils) determined for gold spot grouper (E. • Diets for fi ngerling mouse grouper with MCFA lipids (such as coconut coioides) and mouse grouper (C. altiv- should contain not less than 41% oil) did increase the rate of fat oxi- elis), respectively. CP in both marine digestible protein (about 55% CP) dation but had a detrimental effect and terrestrial animal meals was well on an as fed (~92-93% DM content) on food intake, and consequently digested (above 76%) by both grouper basis. also on growth rate. species with the exception of oven- dried blood meal, which was poorly

January-March 2005 31 Marine Finfi sh Aquaculture Network

digested (55%). The protein digestibil- Table 1. Apparent digestibility (AD) of crude protein (CP) and energy ity of plant products was more vari- (E) of diets and specifi c growth rate (SGR), dry matter (DM) food able (from 43 to 100%) with high fi bre conversion ratio (FCR), DM body fat (BF) and retention of digestible N meals such as rice bran and lucaena (RDN) and digestible E (RDE) of juvenile mouse grouper. (ipil-ipil) meal being poorly digested. The DM digestibility of the meals was Response CP (%) Lipid (%) adversely affected by the amounts of 38 43 49 54 59 14 22 ash and fi bre they contained. A colla- ADCP (%) 46.8C 55.3BC 58.5A 69.7A 74.0A 59.8 61.9 tion of the DM and CP apparent digest- ADE (%) 59.9A 58.4B 51.3C 61.3B 68.1A 62.2X 57.5Y ibility values of the tested ingredients is SGR (%/d) 1.12C 1.11C 1.26B 1.42A 1.52A 1.31 1.26 presented in Table 3. FCR (g:g) 1.58C 1.49C 1.24B 1.08A 1.00A 1.28 1.27 BF (%) 23.5 23.2 23.7 23.1 23.5 21.7X 25.1Y Nutrient requirements of juvenile RDN (%) 58.6A 48.8B 50.3B 42.3C 38.8C 48.9 46.7 groupers RDE (%) 35.0C 38.6C 52.3A 47.5B 44.2B 40.7Y 46.3X A,B,C; X,Y Within comparisons, means without a common letter differ (P < 0.05). Growth rate and survival of sea-caged mouse groupers were improved when Table 2: Percentage distribution of radioactivity following ingestion of diets were supplemented with up to 150 14C-labeled diets containing varying inclusion rates of either coconut mg/kg of vitamin C as the heat-stable oil (MCFA) or olive oil (LCFA). form of L-ascorbyl-2-monophosphate- Na-Ca. This benefi t of vitamin C Diet label Distribution of radioactivity (%)

supplementation was most apparent fol- Fish Respired CO2 DOM POM lowing heavy fl ood rains, which caused 15% LCFA 70B 15B 11B 3.9B a marked deterioration in the turbidity 30% LCFA 67B 11B 11B 11.5C and dissolved oxygen content of the 15% MCFA 23A 51A 26A 0.6A water around the cages. The dietary 30% MCFA 17A 49A 34A 0.6A requirement for the essential omega- A,B,C Means in the same column with different letters differ (P <0.05). 3 highly unsaturated fatty acids (n-3 DOM = Dissolved organic matter in metabolic chamber water. HUFA) was examined for mouse and POM = Particulate organic matter (faeces and in some cases, regurgitated feed) tiger grouper. Increasing the supple- in metabolic chamber water. mentation rate up to 1-1.5% of the diet resulted in improved fi sh growth rates Figure. 1: Relationship between the digestible N and better survival. In studies examin- content of the diet and the amount of digestible ing the capacity of mouse grouper to N required per kg weight gain of fi sh fed diets utilize different types of carbohydrate containing either 14 (▲) or 22 (■) % lipid. as energy sources, best results were achieved using glucose while starch and sucrose were the least effective. These nutrient requirement studies indicate that juvenile groupers require diets that are high in digestible CP (around 45-50%), moderately low in lipid (around 10%) and contain not less than 1.0% and preferably 1.5% of n-3 HUFA. Addition of at least 100 mg of a heat stable form of vitamin C per kg of diet is recommended and this should be increased to 150 mg/kg if stressful culture conditions are likely to occur.

Fishmeal replacement studies

In studies examining the ability of ter- restrial protein meals to substitute for feed conversion or survival of the fi sh. shrimp head meal was used at inclusion fi shmeal in formulated feeds for juve- Other terrestrial protein meals such as rates above 10% as a replacement for nile gold spot grouper, a 4:1 combina- cowpea, corn gluten, lucaena (ipil-ipil) fi shmeal protein. tion of meat meal and ring-dried blood meal and soybean meal were less suc- In laboratory and fi eld cage studies, meal, respectively was able to replace cessful as fi shmeal replacements. With a practical low-cost pelleted dry diet up to 80% of fi shmeal protein in the mouse grouper, growth rate and feed was formulated on a digestible nutrient diet without adverse effects on growth, conversion deteriorated markedly when basis to meet the requirements of juve-

32 Aquaculture Asia Magazine Marine Finfi sh Aquaculture Network

Figure. 2: The amount of consumed dietary lipid Figure 3: Respiration rate of fi sh following retained as body fat or oxidized by fi sh fed either ingestion of diets containing coconut oil (MCFA) or a low lipid (6%) control (Con) diet or diets with 15 olive oil (LCFA) added at 15 or 30% of the diet. or 30% added olive oil (LCFA) and 15 or 30% added coconut oil (MCFA).

Table 3. The dry matter (DM) and crude protein (CP) apparent digestibility (AD) of selected feed ingredients determined for gold spot grouper in the Philippines and for mouse grouper in Indonesia

Feed ingredient Gold spot grouper Mouse grouper DMAD1 CPAD1 DMAD1 CPAD1 Marine product Fishmeal (Chilean 65% CP) 84 ±3.1 98 ± 0.7 Fishmeal (mixed 45% CP) 59 ±1.2 82 ± 2.0 59 ± 1.2 82 ± 2.0 Fishmeal (sardine 65% CP) 87 ± 2.5 93 ± 1.4 Fishmeal (tuna 50% CP) 75 ± 3.6 76 ± 1.9 Fishmeal (white 69% CP) 89 ± 1.7 99 ± 0.3 Shrimp meal (Acetes 72% CP) 76 ± 4.0 95 ± 0.7 Shrimp head meal (50% CP) 59 ± 3.3 78 ± 1.3 Squid meal (71% CP) 99 ± 1.0 94 ± 0.2 Terrestrial animal product Blood meal (Australian ring 84% CP) Blood meal (oven dried 84% CP) 48 ± 0.9 55 ± 1.4 Blood meal (formic 87% CP) 68 ± 1.6 88 ± 0.6 Blood meal (propionic 84% CP) 62 ± 2.6 84 ± 0.7 Meat meal (Australian 44% CP) 61 ± 0.8 99 ± 1.3 Meat meal (Philippine 45% CP) 78 ± 0.1 84 ± 1.7 Meat solubles (73% CP) 99 ± 0.5 98 ± 0.1 Poultry feather meal (67% CP) 74 ± 3.1 82 ± 2.6 Plant product Corn germ meal (8% CP) 85 ± 2.8 83 ± 4.7 Corn gluten meal (56% CP) 94 ± 2.0 99 ± 0.7 Cowpea meal (white 24% CP) 74 ± 3.1 94 ± 1.2 Lucaena (ipil-ipil) meal (19% CP) 56 ± 0.1 79 ± 2.6 Lupin albus meal (26% CP) 54 ± 1.2 98 ± 3.7 Palm oil cake meal (11% CP) 45 ± 2.4 81 ± 1.3 Rice bran meal (11-14% CP) 69 ± 7.0 43 ± 5.4 22 ± 1.5 60 ± 1.4 Soybean concentrate (54% CP) 76 ± 4.9 86 ± 0.4 Soybean meal (full-fat 41% CP) 55 ± 2.7 67 ± 1.3 Soybean meal (solvent 51% CP) 76 ± 1.7 96 ± 0.1 Wheat fl our (9% CP) 73 ± 0.9 83 ± 1.3 1 Mean ± SD.

January-March 2005 33 Marine Finfi sh Aquaculture Network

nile gold spot grouper and compared with feeding either a commercial pellet Feed development and application for diet or fresh fi shery bycatch. In both studies, fi sh fed the project formulation juvenile grouper diet survived and grew as well as those fed the fresh bycatch. In the labora- Ketut Suwirya and Nyoman Adiasmara Giri tory study, fi sh fed the commercial pellet diet grew signifi cantly slower Gondol Research Institute for Mariculture, P.O. Box 140 Singaraja 81101, Bali and converted feed less effi ciently than Indonesia. E-mail: [email protected] those fed either the project diet or fresh bycatch. The analysis of the commer- Groupers are potentially important Nutrient requirements of cial pellet diet showed a sub-optimal aquaculture species since they have juvenile groupers specifi cation. When the commercial a high economic value. Groupers, mill adjusted the formulation to meet predominantly Epinephelus spp, have Dietary protein and lipid these specifi cations, fi sh fed that diet been cultured throughout Asia for requirements in the fi eld study performed as well as many years with commercial produc- those fed either the project diet or fresh tion based on captured wild seed and Tiger grouper (Epinephelus fuscoguta- bycatch. the fi sh reared on trash fi sh. Recently, tus) and humpback or mouse grouper hatchery technology has been devel- (Cromileptes altivelis) are carnivorous Conclusions oped for seed production of some fi sh and thus naturally have a high grouper species and this has stimulated requirement for dietary protein. Grow- The research carried out in the project interest in grow-out farming. However, out studies have examined the optimum has conclusively shown that juvenile the continued use of trash fi sh as a feed dietary protein and lipid specifi ca- groupers will readily accept pelleted source for groupers should be discour- tions for juvenile tiger and humpback dry diets. Diets formulated to meet aged because of the risk of disease groupers. A signifi cant interaction be- the fi sh’s requirements for digestible transfer and the environmental prob- tween dietary protein and lipid has been nutrients, and not containing exces- lems associated with its use. observed for growth rate. Although fi sh sive amounts of plant protein meals, Feed is often the single largest cost productivity generally increases with will enable juvenile groupers to grow item in fi sh culture. Although trash fi sh increasing dietary protein, feeding with as well, if not better, than those fed is presently the fi rst choice of farmers 9% lipid feed was found to be better fresh fi shery bycatch. Further research for on-growing groupers, its avail- than feeding either the 6 or 12% lipid is needed in the areas of essential fatty ability can be limited and varies with feeds. Food conversion ratio (FCR) acid requirements of tiger groupers (E. season. Information on the nutrient improved and more dietary lipid was fuscoguttatus) and to examine whether requirements of groupers is still very retained as dietary protein increased; the nutritional requirements of groupers limited and it is imperative that this retention of dietary lipid also increased above 200-300 g are different to juve- is addressed if cost-effective and high with increasing lipid content of the diet. niles of 10-100 g size. Another area of performing artifi cial feeds are to be de- There was a slight difference between potential research is to develop nursery veloped to replace the feeding of trash tiger and humpback groupers in the op- feed formulations and to develop fi sh. Based on the limited available in- timal dietary protein specifi cation: 47% management practices for successful formation on the nutrient requirements for juvenile tiger grouper and 54% for weaning of fry from live/fresh feeds to of groupers, some feed companies have humpback grouper. In another series of a pelleted dry feed. produced feeds for nursery and grow- experiments, fi ve levels (0.0, 3.0, 6.0, out. However, these have not been well 9.0, and 12%) of dietary lipid were fed accepted by grouper farmers because to juvenile tiger and humpback grouper. they are thought to be expensive and This confi rmed the earlier results with the fi sh do not accept it as well as trash the optimal dietary lipid found to be Free aquaculture fi sh. In order to develop a better artifi - 12 and 9%, respectively for juvenile cial feed for juvenile groupers, a series tiger and humpback grouper. Thus for publications ? of experiments have been conducted juvenile tiger and humpback groupers, at Gondol to increase our knowledge pelleted diets of about 90% dry matter about the dietary requirements of sev- (DM) should contain around 50% pro- eral grouper species. tein, 9-12% lipid, about 4.5 kcal gross www.enaca.org energy/kg (18.8 MJ/kg) and a protein to energy ratio of 120 mg/kcal (27 g/MJ).

No problem.

34 Aquaculture Asia Magazine Marine Finfi sh Aquaculture Network

Essential fatty acid requirements exhibited as slow growth, weak sickly and to ensure that the fi sh’s immune fi sh, anemia and death in severe cases. system is fully functional. Omega 3 or n-3 highly unsaturated Vitamin C is very important for main- Another experiment has been con- fatty acids (HUFA) such as eicosapen- taining a strong immune system and ducted to determine the requirement taenoic acid (EPA) and docosahexae- any defi ciency will increase the fi sh’s of vitamin B6 (pyridoxine). This is noic acid (DHA) are essential dietary susceptibility to stress and disease. Pure another important and essential vita- fatty acids for marine fi sh. Require- ascorbic acid is very easily destroyed min for fi sh and in severe defi ciency ment for n-3 HUFA varies with the by mild heating and exposure to light. neurological disorders such as erratic species and size of fi sh. Experiments To overcome the low stability of and spiral swimming, shock reaction to have examined the n-3 HUFA require- ascorbic acid, other more stable types stress or handling and death are seen. ment of juvenile humpback and tiger of vitamin C have been developed. In a less severe defi ciency, the signs groupers. Juveniles of average starting Some products are simply ascorbic are fairly non-specifi c such as poor ap- body weight of 5 ± 0.7 g were reared acid coated by glycerine or some other petite and slow growth rate of the fi sh. for 9 weeks in 100 L tanks and supplied fi lm which helps to reduce exposure of Fortunately, pyridoxine hydrochloride, with fl ow through seawater. Fish were the ascorbic acid to light and so slow which is the commonly available form fed one of six feeds that provided n-3 its destruction. However, these coated of pyridoxine, is very stable to heat HUFA levels of 0, 0.5, 1.0, 1.5, 2.0 or ascorbic acid products are still not very and light. To determine the pyridoxine 2.5%. Based on growth rate and FCR, stable and are mostly destroyed dur- requirement of groupers, six levels of the optimal dietary n-3 HUFA specifi - ing any type of hot pelleting process. pyridoxine (0, 20, 40, 60, 80 or 160 cation was found to be 1.5 - 2.0% for Ascorbyl phosphate is a much more mg/kg) were fed to juvenile hump- humpback grouper and 1.75 –2.8% for stable form of vitamin C, which has back groupers for 98 days. Using the tiger grouper. been shown in other fi sh species to be increase in blood haemoglobin as an in- effective in meeting the fi shes nutri- dex of pyridoxine adequacy of the feed, Vitamin requirements tional needs. To evaluate its effective- the optimal specifi cation for maximum ness for groupers, juvenile humpback blood haemoglobin was 60 mg/kg. This Similar to all other carnivorous marine groupers of about 14 g starting weight is much higher than the 15-20 mg/kg fi sh, groupers require a dietary source were fed feeds containing 0, 15, 30, 60, dietary specifi cation recommended for of vitamin C (ascorbic acid). A lack of 120 or 250 mg/kg of ascorbyl phos- many other marine fi sh. Since pyridox- vitamin C in very young fi sh will result phate magnesium (APM) for 126 days. ine HCl is quite soluble and groupers in skeletal deformities such as lordosis Based on the results of this experiment, are fairly slow feeders, this higher and scoliosis (curvature of the skeleton) it is recommended that pelleted grouper specifi cation may be due to leaching of and deformity or absence of the gill feeds should contain not less than 30 pyridoxine from the feed. In any event, opercula; in older fi sh a defi ciency is mg APM/kg for maximum fi sh growth it is recommended that grouper feeds have a dietary pyridoxine HCl specifi - cation of 40-60 mg/kg to maintain the Table 1. Formulation and macro nutrient composition of the Gondol healthy condition of fi sh. practical feed formulation for juvenile groupers Practical feed development Ingredient Formulation Nutrient Composition for juvenile groupers (%) (% of diet) Fishmeal (65% CP) 55 Crude protein 46-50 Fishmeal replacement Soybean meal 10 Total lipid 9-13 Squid liver meal 14.5 Fiber 6-7 Fish meal is the main source of protein Mysid shrimp meal 6 Ash 18-25 in conventional pelleted feeds for most Squid oil 6 fi sh species. Because capture fi sheries Trace mineral mix 2.5 production has not increased since the Vitamin mix 2.0 early 1990’s and production of fi shmeal CMC binder 4.0 has similarly not increased but aquac- Total 100 ulture’s demand has skyrocketed, it is not surprising that the price of fi shmeal Table 2. Result of a 4-month feed comparison trial with humpback continues to increase at rates above grouper in net cages infl ation. In an attempt to offset the spiraling cost of fi shmeal as an ingre- Productivity traits Test diets dient in pelleted fi sh feeds, there has Gondol feed Commercial feed Trash Fish been a lot of research worldwide to fi nd Initial weight (g) 36.0 36.0 36.0 cheaper protein alternatives. At Gondol, Final weight (g) 147.6 132.8 133.4 we have examined the extent to which Survival rate (%) 98.7 98.0 95.1 soybean meal can be used to replace FCR 1.39 1.54 5.82 Haematocrit (%) 37.3 38.2 24.2 Continued on page 46...

January-March 2005 35 Marine FinPresentfi sh Aquaculture status Network in the development of culture technology for the silver pomfret Pampus argenteus

Sulaiman M. Almatar and Charles M. James

Kuwait Institute for Scientifi c Research, Aquaculture, Fisheries and Oceanography Department, P.O. Box 1638, Salmiya 2201, Kuwait

Silver pomfret about 35 days old after hatching.

The silver pomfret Pampus argenteus, cess of 1997 larval rearing, a fi ve-year July when the water temperature ranges locally known in Kuwait as ‘zobaidy’, research project was initiated in April from 28-29ºC. is a high priced food fi sh having 1998 to assess the technical feasibility Fully ripe gravid females, with worldwide market demand. It is also of silver pomfret culture in Kuwait. hydrated and free-fl owing eggs, occur extensively distributed in different Since then the project has success- between 15:00-18:00 hours during ebb regions of the world from the East fully produced several thousand silver tides. In the gillnet catch, fully mature China Sea to Southeast Asia, Indian pomfret fi ngerlings for nursery and males outnumber the females at an Ocean and in the Arabian Gulf. In grow-out production and developed lar- average ratio of 5:1. Males also mature recent years the silver pomfret capture val rearing techniques to grow-out fi sh earlier with a much lower gonado- fi shery from the wild has been declin- to marketable size. Continued efforts somatic index (GSI) than females. ing in Kuwait and in other regions due are underway to develop domesticated Fecundity and histological studies to over fi shing. In spite of the decline broodstock for spawning under control- indicate that the broodstock is inde- in wild stock and increasing market led culture conditions. terminate showing that a female may price, there has been little research on spawn at least six batches of eggs from developing technology for the hatchery Hatchery performance June to August with an average rela- and grow-out culture of this species tive batch fecundity of 170.6 eggs/g until recent years. During June 1997, The present source of eggs for larval of somatic weight. Total fecundity of in a preliminary attempt to develop rearing is based on stripping wild a 500g female is about 350,000 eggs. hatchery and larval rearing techniques, caught spawners. Fully mature males An average of about 40,000-60,000 the Aquaculture Fisheries and Ocea- and gravid females are found dur- viable eggs can be collected from each nography Department (AFOD) of the ing June to September in the coastal ripe female, depending on the size and Kuwait Institute for Scientifi c Research waters of Kuwait at about a depth of condition of the ovary. The percentage (KISR) succeeded for the fi rst time 5-20 m. They are captured with drifting of viable eggs depends on the fi shing in the world in larval rearing and fry gillnets in the daytime during spring season/month and accordingly the high- production of Pampus argenteus under tides at new and full moon. During the est percentage of viable eggs are col- hatchery culture conditions. This was spawning period, the surface seawater lected during June. The fertilized eggs achieved using eggs stripped from wild temperature ranges from 28-33 ºC and are spherical, transparent and pelagic spawners caught by drifting gillnets, the water ranges from 35-39 and about 1.1mm diameter in size. The with 45 larvae successfully grown to ‰. The peak spawning period is June- egg hatching time is 15 hours at 29-30 juvenile stage. Pursuant to the suc- ºC. The hatching rate depends on the

36 Aquaculture Asia Magazine Marine Finfi sh Aquaculture Network

Above: Fertilized eggs and embryo development of silver pomfret. Below: Newly hatched larvae.

Stripping for egg collection from wild spawners. acceptance of forumulated feeds make egg collection time and conditions and more, the essential ω3 HUFA were also the hatchery techniques developed thus normally it ranges from 28-50%. The signifi cantly higher in rotifers treated far promising for commercial ventures. newly hatched larvae have a large el- with mixed species of along with Further research studies to refi ne larval lipsoid yolk and measure about 2.4 mm commercial enrichment media ‘Su- rearing are in progress, focussing on in total length. per Selco’ and ‘DHA Protein Selco’. feed and tank management techniques Within a week of feeding on Artemia to enhance fry production. Larval rearing nauplii, the larvae could be weaned to a formulated paste feed. The larvae are Grow-out culture The optimal temperature for rearing also easily trained to accept the paste larvae is 27-29 ºC and salinity 39-40‰. feed kept in trays suspended in the wa- To date the grow-out culture of silver The newly hatched larvae are generally ter column. Under experimental culture pomfret has been restricted to land- stocked at a density of 30-120 larvae conditions the survival was up to 4.2% based culture systems using different per litre. However, stocking rates of 20- to juvenile stage. Mass larval rearing capacity round circular tanks of up 40 larvae per litre are conventionally and fry production using 1m3 and 4m3 to 65 m3 with fl ow-through seawa- used without any signifi cant difference capacity round fi berglass tanks showed ter. Screening for a commercial feed in larval survival at these stocking that better larval survival is achieved in suitable for use in the grow-out phase densities. Signifi cantly higher survival larger tanks. One of the reasons for lar- is still in progress. In the meantime, rates at 12 days after hatching were val mortality in the hatchery is due to based on the results obtained from observed for larvae fed on a combina- a behavior of the larvae in swallowing various experiments, a semi-moist feed tion of mixed species of micro-algae tiny air bubbles at the water surface. is used. The feed is kept in a plastic consisting of Chlorella, Isochrysis This is due to the innate feeding habit bowl, which is suspended in the water and Nannochloropsis at a cell density of silver pomfret, which consume small column. In trials between 1998-2003, of 1 million cells per ml in the larval jellyfi sh and medusae. As tiny air bub- the average weight gain for fi sh of less rearing waters along with nutritionally- bles may mimic jellyfi sh in appearance, than 50g was up to 0.34g per fi sh per enriched rotifers, compared to those the larvae consume them and tend to day and 0.23 g per day in fi sh above reared using a single algal species. First fl oat, losing their balance in the water 50g. Due to feed improvements made larval feeding is with rotifers at a densi- column. This phenomenon increases through feed additives in 2004, the ty of 5 rotifers per ml until 6 days after during the later part of the larval rear- growth rate for fi sh less than 50g in hatching, and then increased to 10-15 ing period from day 25. Larval mortal- size has been increased to 0.62g per rotifers per ml since prey consumption ity due to air-bubble ingestion has been fi sh per day and in the above 50g size by the larvae increases signifi cantly at substantially reduced by introducing group it has been increased to around 8 days until they are weaned to newly indirect aeration techniques instead of 1.32g per fi sh per day. During this hatched Artemia nauplii. Larval feeding using air-diffusers directly in the larval period the specifi c growth rate (SGR) on rotifers is signifi cantly higher in tanks. Larval mortality due to can- was up to 5.98% per day for fi sh in the cultures with mixed species of algae nibalism is low in the hatchery phase below 50g size group and about 2.13% compared to those using a single algal compared to other marine fi sh species. per day for fi sh above 50g. The growth species in the culture system. Further- The lack of cannibalism and ready rate declines during the winter period

January-March 2005 37 Marine Finfi sh Aquaculture Network

About 45 days old after hatching.

in Kuwait from November to March ing tank culture system showed that earthen ponds and sea-cages is yet to be when the water temperature drops to better survival could be obtained at a investigated. 13 ºC. Growth performance of this fi sh stocking density of 60 fi sh/m3. Growth stocked at different densities of 60, 80, performance of silver pomfret using Domesticated broodstock 100 and 120 fi sh/m3 in a re-circulat- development

During the grow-out culture, fast growing selected fi sh were maintained in separate tanks for the development of domesticated broodstock. Histo- logical studies have shown that silver pomfret are a gonochoristic species, in which the male and female sex exists in separate individuals. The studies also show that the processes of sexual differentiation for the male and female are completed at the ages of 115 and 135 days after hatching from the egg, respectively. Under tank culture conditions, fully grown broodstock size ranged from 124 to 823g. The fi sh selected for broodstock development were found to undergo gonad matura- Grow-out culture of silver pomfret. tion in captivity as evidenced by the

38 Aquaculture Asia Magazine Marine Finfi sh Aquaculture Network occurrence of fully ripe male producing milt at a size of 134g in body weight and 17cm in fork length (FL). The fi rst occurrence of female maturation in the broodstock holding facility was with stage-2 gonad at the size of 222.5g in body weight and 19.5cm in FL. During July 2004 a 408g female with a stage- IV ovary was observed. However, the broodstock holding tank was infested with Cryptocarion and mass mortality of the fi sh occurred hampering further progress in spawning of the broodstock during 2004. Further investigations are in progress towards developing domesticated broodstock from hatchery produced individuals. Towards achiev- ing spawning in the broodstock holding facility, efforts made to inject the fi sh with chorionic gonadotrophin (HCG) failed to yield any results. The poten- Hatchery produced potential broodstock. tial spawners were also not tolerant to handling and injection stresses, par- and development. Compared to some with very high potential market price ticularly in the case of wild brooders. of the economically important farmed and demand, especially in the Middle Techniques for the spontaneous natural tropical marine fi sh species, the re- East Marineand in South East Fin Asia.fi sh spawning of the captive broodstock search on silver pomfret has only been using improved tank management and initiated relatively recently and should Aquaculture feeds are yet to be developed. be considered at the initial stages of development, although substan- Network Future prospects tial progress has been made towards commercial applications. Based on In general, developing commercial the results achieved so far, the silver www.enaca.org/marinefi sh culture technologies for marine fi sh pomfret Pampus argenteus seems to be species takes many years of research an excellent candidate for aquaculture

A 408g cultured female with stage-IV ovary

January-March 2005 39 Marine Finfi sh Aquaculture Network

Best practices for using trash fi sh in the culture of juvenile Malabar grouper, Epinephelus malabaricus

Le Anh Tuan

Faculty of Aquaculture, University of Fisheries, Nha Trang, Vietnam. Email: [email protected].

can result in a lot of the trash fi sh be- ing wasted and as a consequence, can cause serious downstream problems. For these reasons, determin- ing best practices for using trash fi sh is a high priority for the Vietnamese grouper industry. This paper describes an experiment comparing different types of trash fi sh and feeding rates for culturing juvenile Malabar grouper.

How the research was done

A 3 x 4 factorial design was used in an 8-week experiment to investigate the effects of feeding juvenile Malabar grouper of initial size 10 ±0.3 g either of three different types of trash fi sh – cardinal fi sh, lizard fi sh or a combina- tion of equal amounts of cardinal fi sh University of Fisheries’ nutritional wet laboratory comprising 48 and lizard fi sh – and four daily feeding experimental tanks. rates – 5, 7, 9 or 11% of fi sh biomass. A total of 480 fi sh were stocked equally Malabar grouper Epinephelus mala- groupers. It is a comparatively inex- into 48 x 100 L polyethylene tanks baricus is a highly valued species in pensive source of feed that is available (four tank replicates per treatment) the live fi sh markets of Vietnam and locally, although its availability and under controlled laboratory conditions. throughout Asia. The recent develop- price does fl uctuate during the year and Each tank was supplied with fl ow- ment of hatchery production technol- it can be scarce and expensive during through bio-fi ltered seawater (33 to 35 ogy for Malabar grouper fry and its the winter typhoon season. However, g L-1) at an exchange rate of 500% day-1 successful exploitation by a commer- poor husbandry and feeding practices and with supplementary aeration. cial hatchery in Vietnam has resulted in a promising supply of fry for aquacul- ture. Commercial culture of grouper in Vietnam relies almost entirely on the feeding of low-value fi sh and fi shery by-product (‘trash fi sh’). In Viet Nam, the species of trash fi sh most com- monly fed are lizard fi sh (Saurida spp.), pony fi sh (Leiognathus spp.), cardinal fi sh (Apogon spp.), anchovy (Stolepho- rus spp.), pomfret (Psenes spp.) and spinefoot (Siganus spp.). Some farmers have a preference for using lizard fi sh and cardinal fi sh. Although grouper aquaculture production in Vietnam is increasing each year and was 3,000 metric tonnes in 2003, the size of the industry is still not large enough to get aquafeed companies involved. ‘Trash fi sh’ will continue to be used in Viet- nam for some years as a major feed for The feed processing laboratory.

40 Aquaculture Asia Magazine Marine Finfi sh Aquaculture Network

By-catch was bought fresh from Effect of feeding rate (Table 3). FCR was almost identical the Cu Lao Trung Fishing Port, Nha for the three lower feeding rates but Trang city and immediately weighed In line with the applied treatment, worsened slightly when the feeding rate into plastic bags and stored at -20ºC daily food intake increased incremen- was increased to 11%. While this may until required to be fed. The trash fi sh tally with increasing feeding rate up be a genuine reduction in the effi ciency was thawed and chopped into pieces to the 9% level with a non-signifi cant with which the grouper used the food, it immediately prior to feeding with the increase thereafter for the 11% rate. As equally could have been due to incom- daily allocation being fed in two equal a consequence, fi sh weight gain showed plete collection of uneaten food since amounts twice daily at 0730 and 1530 a parallel response with signifi cantly some feed refusal was common at this h. Uneaten food was collected, oven better grouper growth rates as the feed- feeding rate. dried and its weight used to calculate ing rate was increased from 5 to 9% Continued on page 45... actual food intake after correcting for leaching loss. Table 1. Effect of trash fi sh type on the productivity responses of juvenile Malabar grouper. What was found Response trait Type of trash fi sh fed There were some very minor interac- Cardinal Lizard Combined ± SEM tions between the type of trash fi sh Weekly gain (g) 4.36C 4.92B 5.13A 0.017 fed and feeding rate but these were so SGR (%/d) 2.61C 2.78B 2.85A 0.013 inconsequential in comparison to the Daily intake 2.94C 3.03B 3.15A 0.007 main treatments that they will be ig- (g as-fed/d) nored in this article. However, produc- FCR (as-fed) 4.70B 4.29A 4.29A 0.017 tivity of the groupers were markedly FCR (DM) 1.19C 0.99A 1.04B 0.004 affected by both trash fi sh type and Survival (%) 93.1B 95.6AB 97.5A 0.98 feeding rate. A,B,C – Within each response trait, means without a common superscript letter are Effect of type of trash fi sh different (P < 0.05). Growth rate, expressed as aver- age weekly gain (AWG) or as specifi c growth rate (SGR), as-fed and dry mat- Table 2. Whole body chemical composition (± SD) of common trash ter (DM) food conversion ratio (FCR) fi sh species caught in the central coast region of Vietnam. and fi sh survival were generally best when cardinal fi sh and lizard fi sh were Analysis Trash fi sh species fed as the combination while feeding Cardinal Lizard Anchovy1 Spinefoot cardinal fi sh by itself resulted in the Fresh basis worst productivity (Table 1). Moisture 74.7±0.99 74.8±0.44 75.7±0.42 74.6±0.42 Lizard fi sh has a higher lipid and Ash 5.3±0.14 3.7±0.08 3.1±0.04 6.5±0.08 lower ash (and thus, higher energy) Protein 16.2±0.07 17.3±0.65 14.9±0.30 13.1±0.74 content than cardinal fi sh (Table 2) Lipid 1.7±0.22 2.6±0.37 1.6±0.19 2.0±0.23 and this most likely explains why the Dry matter basis Malabar grouper grew better when Ash 21.0±0.55 14.7±0.33 12.9±0.15 25.4±0.30 fed the lizard fi sh. However, why a Protein 64.0±0.09 68.7±0.88 61.3±0.60 51.6±0.98 combination of the two trash fi sh types Lipid 6.7±0.65 10.3±0.75 6.6±0.38 7.9±0.46 should result in better grouper produc- 1 Long-jaw anchovy. tivity than either alone is not so easily explained. Clearly, the combination Table 3. Effect of feeding rate on the productivity responses of of trash fi sh was more preferred by juvenile Malabar grouper. groupers than either type alone since food intake was signifi cantly higher for Response trait Feeding rate (% of biomass per day) the combination. This perhaps explains 5 7 9 11 ± SEM the better growth of the groupers on Weekly gain (g) 3.06C 4.44B 5.87A 5.84A 0.020 the combination but it does not explain SGR (%/d) 2.15C 2.70B 3.05A 3.08A 0.015 the signifi cantly better DM FCR that Daily intake 1.90D 2.76C 3.65B 3.85A 0.008 was also observed for the combination. (g as-fed/d) The improved FCR suggests that the FCR (as-fed) 4.36A 4.36A 4.36A 4.63B 0.020 combination provided an overall better FCR (DM) 1.06A 1.06A 1.05A 1.12B 0.005 nutritional profi le for the groupers but Survival (%) 90.8C 95.0B 99.2A 96.7AB 1.13 in what respects is not known. A,B,C – Within each response trait, means without a common superscript letter are different (P < 0.05).

January-March 2005 41 Marine Finfi sh Aquaculture Network

Grouper grow-out feeds research at Maros Research Institute for Coastal Aquaculture, South Sulawesi, Indonesia

Usman1, Rachmansyah1, Asda Laining1, Taufi k Ahmad2

1 Research Institute for Coastal Aquaculture, Jl. Makmur Dg. Sitakka, No. 129, Maros, Sulawesi Selatan, 90512, Indonesia. E-mail: [email protected]; 2 Central Research Institute for Aquaculture, Jl. KS. Tubun VI, Slipi PO. Box 50, Jakarta Pusat, Indonesia.

In Sulawesi, the development of able feed ingredients and examining training the fi sh to accept pelleted feeds grouper aquaculture is hindered by their potential as partial replacements without losing condition that otherwise dependence on the fl uctuating and un- for imported fi shmeal, and investigating frequently occurs when only dry feed certain supply of perishable trash fi sh. the nutrient requirements of juvenile pellets are fed. While some commercially produced mouse (Cromileptes altivelis) and tiger Results of past research are outlined pelleted grouper feed is imported from (Epinephelus fuscoguttatus) groupers. in this article and some information Java and Thailand, it is expensive and While much of this past research has is given about producing farm-made fi sh that have previously been fed on involved feeding acclimatized fi sh on moist pellets for feeding juvenile trash fi sh do not readily adapt to dry laboratory-made dry pellets, our current mouse and tiger groupers. pellets, resulting in slower fi sh growth. research emphasis is to adapt these To address this problem, grouper feed fi ndings for the production of moist Apparent digestibility of research at Maros has focused on ex- pelleted feeds that can be made on-farm Sulawesi feed ingredients amining the potential of locally avail- using simple equipment. Moist pelleted able meals as ingredients in farm-made feeds are well accepted by juvenile To date, the apparent digestibility of feeds. This has entailed determining the groupers and can be used as the only nine locally available feed ingredi- apparent digestibility of locally avail- food source or alternatively as a way of ents have been determined for mouse

Dry ingredients and fi sh oil being weighed prior to being hand mixed together with the minced fi sh.

42 Aquaculture Asia Magazine Marine Finfi sh Aquaculture Network grouper. These feed ingredients are available throughout the year and in suffi cient quantities to justify this research. Each of the feed ingredients was incorporated in a reference diet at an inclusion rate of typically 30% and its apparent dry matter, crude protein and energy digestibility determined by reference to the digestibility marker, chromic oxide. Although these studies were carried out using mouse groupers, it is expected that other grouper species would show similar results. The out- comes of the experiments are summa- rized in Table 1. The data shows that protein con- tained in shrimp head, formic and propionic blood, sardine, mixed-fi sh and palm oil cake meal is well digested Preparation of moist feed pellets (noodles) using simple on-farm equipment. A by mouse grouper. However, the low kitchen meat mincer is used to mince the trash fi sh. The mixed dough is extruded dry matter and energy apparent digest- through the meat mincer and the resultant noodles subsequently broken into ibility of palm oil cake meal and rice suitable lengths for feeding to groupers. bran meal indicates that groupers do not use these meals very well. The be used at inclusion rates above 10% hydrate in the feed formulation would comparatively poor digestibility of soy- as a substitute for fi shmeal in grouper provide the fi sh with an alternative bean meal, especially that of protein, feeds. The high content of chitin in the source of energy instead of breaking was surprising and indicate that it may shrimp head meal may explain the poor down absorbed protein for this purpose. not be very suitable as a replacement performance of the fi sh fed these feeds If carbohydrate can be digested and for fi shmeal in compounded feeds for since the chitin would likely be poorly effectively metabolized it would enable groupers. Not unexpectedly, the oven- digested by the fi sh. the amount of protein in the feed to dried blood meal was not well digested be reduced, lowering both the cost of but this could be markedly improved by What carbohydrate is best the feed and reducing the excretion of organic acid fermentation. for groupers? nitrogen to the water. The results of the work are shown in Table 3. Replacement of fi shmeal A 6-week growth and nutrient retention As shown by the data in Table 3, experiment was carried out to compare glucose was the most effective type A 9-week growth experiment was car- four different types of carbohydrate of carbohydrate, resulting in higher ried out with mouse grouper to see if – dextrin, starch, sucrose and glucose growth rates and higher retentions of shrimp head meal could be used as a – when each was included at a similar protein and energy. Starch and dextrin partial replacement for fi shmeal. Fish inclusion of 16%. The object of this were the next best while sucrose was were held in 1 x 1 m seacages and fed study was to see if including carbo- the least effective type of carbohydrate. twice daily. Five diets were examined in which shrimp head meal at 10% Table 1. Dry matter, crude protein and gross energy apparent inclusion increments from 0 to 40% digestibility coeffi cients (%) of locally available feed ingredients in were used to substitute for fi shmeal on Sulawesi. an isonitrogenous basis. Table 2 shows the results of this experiment. Ingredient Dry matter Crude protein Gross energy Although survival rate was unaf- Shrimp head meal 59 78 64 fected by the amount of shrimp head Soybean meal (full-fat) 55 67 51 meal in the feed, most other response Palm oil cake meal 45 81 40 characteristics became worse with in- Dried blood meal1 48 55 ND creasing inclusion of shrimp head meal. Formic blood meal2 68 88 ND The reduced intake associated with Propionic blood meal3 62 84 ND increasing amounts of shrimp head Local sardine meal 87 93 85 meal is most likely a dual effect of the Local mixed-fi sh meal 59 82 77 fi sh not liking this feed and the smaller Rice bran meal 22 60 44 size of the fi sh resulting from the lower ND: Not determined as insuffi cient faecal sample for energy analysis. biological value of feeds containing the 1 Whole cattle blood recovered from slaughterhouse and oven dried. shrimp head meal. The results sug- 2 Oven dried cattle blood following fermentation using formic acid. gest that shrimp head meal should not 3 Oven dried cattle blood following fermentation using propionic acid.

January-March 2005 43 Marine Finfi sh Aquaculture Network

Since glucose is not a standard feed ing non-stabilized ascorbic acid grew Moist feeds ingredient and starch and sucrose were poorly, hardly better than those fed the not very effective as alternative energy zero APNaCa feed, and survival was Although the above studies were car- sources, it seems that carbohydrates low. Adding APNaCa at rates of 150 ried out using pelleted dry feeds, cur- will not have a useful role in grouper mg/kg feed is advised and especially if rent research is examining moist pellets feeds for protein sparing. culture conditions may be stressful. as a cost-effective way of providing feeds for groupers. Moist pelleted feeds Vitamin C requirements have many advantages for the small- scale grouper farmer: Carnivorous fi sh such as groupers do not have the capacity to synthesize vitamin C and neither do they carry Table 2. Biological response of mouse grouper to feeds containing suffi cient microorganisms in their increasing amounts of shrimp head meal. digestive tract to provide a non-di- etary supply of this vitamin. Vitamin Variables Shrimp head meal (%) in the diet C has many physiological functions, 010203040 including maintenance of epithelial Weight gain (%) 101.5a 102.6a 76.8b 67.9b 27.8c tissue functionality and maintaining DGC (%/d) 1.17a 1.14a 0.85b 0.84b 0.51c the fi sh’s immunity system. In larval Feed conversion ratio 1.52a 1.55a 1.79b 1.78b 2.64c fi sh, a defi ciency of vitamin C leads Feed intake (g/week) 23.2a 23.0a 19.6b 19.0b 13.8c to skeletal and other deformities while Protein effi ciency ratio (g:g) 1.35 1.36 1.34 1.19 0.89 in older fi sh, a defi ciency will cause App. digestibility coeffi cient (%) 85.2a 86.9a 81.3b 79.6b 81.9b slow growth, increased mortality and Survival rate (%) 100a 96.7a 95.0a 98.3a 96.7a reduced resistance to disease. Ascor- a,b,c Values in the same row with a similar superscript letter are not signifi cantly bic acid, which is the active chemical different (P>0.05). of vitamin C, is very easily destroyed DGC – Daily growth coeffi cient (100 times the difference between start and by ultra violet light and heating. To end weights raised to the one third power and divided by the number of days on overcome this problem, and especially experiment). where feed is pelleted by hot extru- sion or steam press, more stable forms Table 3. Biological response of mouse grouper fed diets containing of Vitamin C have been developed. different types of carbohydrate. One such product is L-Ascorbyl-2- phosphate-sodium-calcium (APNaCa). Variables Source of carbohydrate An 8-week experiment was carried Glucose Sucrose Dextrin Starch out with groupers held in seacages to Absolute growth rate (g/d) 0.40c 0.27a 0.34b 0.34b test the effi cacy of this product as a Feed effi ciency (%) 100.8c 78.6a 91.2b 90.1b source of vitamin C. In the experiment, Protein retention (%) 35.0c 26.2a 33.1c 29.7b four incremental levels of APNaCa Lipid retention (%) 67.8b 45.7a 53.9a 49.8a from 0 to 150 mg/kg were examined Survival rate (%) 100a 100a 100a 100a and compared with feed of the same App. digestibility of NFE 96.6a 87.7b 82.8b 69.3a formulation but in which a proprietary App. digestibility of protein 94.4b 93.4a 94.6b 94.8b vitamin premix was used. The vitamin App. digestibility of lipid 97.2a 96.2a 95.6a 95.3a C in the proprietary premix was in an a,b,c Values in the same row followed by a similar superscript letter are not sig- unstable form. The results of this study nifi cantly different (P>0.05). are shown in Table 4. In the experiment, fi sh performance improved with increasing supplementa- Table 4. Weight gain, daily growth rate, feed effi ciency and survival tion of APNaCa with the best growth rate of mouse grouper fed different levels of APNaCa. seen at the highest amount of 150 mg/ kg. Interestingly, most of the difference Variable Comm. APNACa level (mg/kg) in growth of the fi sh occurred in the premix last few weeks of the experiment when (control) severe fl ooding caused a marked dete- 0 50 100 150 rioration in water quality. Compared to Weight gain (%) 120a 110a 170b 187b 254c fi sh fed the low vitamin C feeds, those DGC (%/d) 1.40a 1.32a 1.78b 1.88b 2.26c fed the higher APNaCa feeds were Feed effi ciency (%) 33.5a 32.0a 49.8b 54.7c 69.9d better able to handle the water qual- Survival rate (%) 72.5a 75a 85b 86.7b 95c ity stress with high survival rates and a,b,c,d Values in the same row followed by a similar superscript letter are not continued good growth. The fi sh fed the signifi cantly different (P>0.05). commercial vitamin premix contain- DGC – As for Table 3.

44 Aquaculture Asia Magazine Marine Finfi sh Aquaculture Network

• They can be easily made on-farm Table 5. Examples of formulations and gross nutrient composition with simple equipment (some form for producing moist pelleted feed for juvenile groupers of meat grinder to mince and cold- extrude the mixed dough to form the Ingredient 1 2 3 4 noodle pellet). Kg (as used) • Reduced dependence on trash fi sh Trash fi sh 50 50 60 60 since only a quarter or less is re- Fishmeal (65% CP) 13 12 10 11 quired compared to using trash fi sh Mussel/snail meat 7 0 0 as the sole source of food. Mysid meal 5 0 0 0 • Enables locally-available ingredients Soybean meal (solvent) 0 15 0 to be used in the formulation. Groundnut meal1 0015 • Enables effective vitamin enrich- Dry blood meal 10 0 0 ment (often defi cient when trash fi sh Rice bran 16 15 9 0 only is fed). Tapioca/cassava starch 0 0 9 • Reduces food wastage (and conse- Wheat gluten 10 0 0 0 quential pollution of the water) as (80% CP) moist pellets are eaten by the fi sh Fish oil2 4443 with minimal loss. Additives3 2222 • Moist pellets can be used to train Total 100 100 100 100 fi sh to accept dry pellets. Nutrient composition (% as fed) There are a couple of disadvantages. Moisture 42 47 50 50 Moist feeds have to be prepared daily Crude protein 29 26.5 24.5 24 (unless refrigeration is available) and Lipid 7.5 7.5 7.5 7 preparation can be time consuming Ash 7.5 6.5 6.5 5.5 and labor intensive. Additionally, some 1 Do not use unless known to be free of fungal mycotoxins such as afl atoxin. knowledge about what feed ingredients 2 Can be deleted but inclusion will produce better fi sh growth. can be used is essential otherwise a 3 Use quality vitamin and trace mineral premixes. nutritionally unsatisfactory feed might be produced. However for a small-scale farmer, the advantages far out weigh the disadvantages. Examples of suitable moist pel- Grouper grow-out feeds... Future research let formulations for feeding juvenile continued from page 41... groupers are shown in Table 5 and The above study was carried out un- the ease with which they can be made Conclusions der closely controlled laboratory condi- on-farm using simple equipment is il- tions. It will be important to see if these lustrated in. This research has demonstrated that fi ndings can be validated under normal trash fi sh can be an excellent food seacage farming conditions. Under Future research source for culturing Malabar groupers such conditions, nutrient losses from with DM FCR’s of less than 1.0 able to the trash fi sh are likely to be greater Past work has focused on feed develop- be achieved under experimental condi- (leading to poorer FCRs and growth ment for mouse grouper and particular- tions. It has also demonstrated that the rates) and the freshness of the trash fi sh ly for juvenile fi sh of 20 to 150 g size. type (species) of trash fi sh used can sig- at feeding is often far from satisfactory. Our focus will now change to examine nifi cantly affect the productivity of the The addition of a vitamin supplement fi sh in the size range of 200 g to market grouper. In this study, lizard fi sh was a and some simple form of binding the size and with an increasing emphasis better species to feed than cardinal fi sh trash fi sh into a more stable food may on tiger grouper since its faster growth although a combination of both gave overcome both of these problems. lends itself better as an aquaculture the best overall result. These productiv- species. Research will also continue to ity response differences of the grouper Acknowledgement determine apparent digestibility of lo- are thought to be due to differences cally available feed ingredients and the in the macro- and/or micro-nutrient This research forms part of my PhD further development of practical moist composition of the trash fi sh being fed. studies under the supervision of Dr feed formulations using locally avail- The best rate to feed the trash fi sh was Kevin Williams, CSIRO Marine Re- able ingredients. found to be 9% of the fi sh biomass with search, Australia and Dr Nguyen Huu the total amount fed as two equal meals Dung, University of Fisheries. Funds a day. Not only did this rate result in for the work were provided by an Aus- the best growth and FCR of the fi sh but tralian AusAID CARD project and this survival was almost 10% higher than support is gratefully acknowledged. feeding at a 5% rate.

January-March 2005 45 Marine Finfi sh Aquaculture Network

Feed development and the vitamin-supplemented trash fi sh. application for juvenile grouper... Interestingly, the haematocrit value Collaborators continued from page 35... (proportion of red cells in the blood – an indirect measurement of haemo- The following organizations and fi shmeal in grouper feeds. Unfortu- globin content) of the grouper fed trash contacts are focal points for com- nately, using soybean meal in amounts fi sh was quite low, suggesting either munication in the network: exceeding 10% of the diet as a protein a vitamin defi ciency (even though a replacement for fi shmeal caused growth vitamin supplement was mixed with the Hong Kong rate and food conversion of the fi sh to trash fi sh) or some other toxic or infec- Dr Jim Chu, jim_cw_chu@afcd. worsen. tious agent present in the grouper. gov.hk

Practical feed formulation for Future research India juvenile groupers Dr Mohan Joseph Modayil, Gondol will continue research to [email protected] A suitable practical feed formulation increase our knowledge about the nutri- for juvenile groupers has been devel- ent requirements of groupers with tiger Indonesia oped at Gondol (Table 1). grouper being the main species to be Dr Ketut Sugama, In a 4-month trial with humpback used for these investigations. A priority crifi [email protected] grouper held in a fl oating net cage, area is to develop successful nursery Dr Muhammad Murdjani, the effectiveness of the Gondol feed feeds in order to quickly and easily [email protected] formulation has been compared against wean fry from live feed (or trash fi sh) a commercial pelleted grouper feed and to pelleted dry feeds. This work will be Iran trash fi sh.Table 2 shows the results of coordinated with other grouper feeds Dr Shapour Kakoolaki, this comparison. Growth rate and FCR research that will be carried out in the [email protected] were best for grouper fed the Gondol ACIAR Marine Finfi sh Technology feed. In terms of growth rate and FCR, Improvement project at Maros Malaysia the commercial feed was as good as (Indonesia). Coastal marine fi sh culture Mr Ali bin Awang, ppbuk@po. jaring.my

Fish quality Mr Ismail Ishak & Mr Hamdan Jaafar anasofi [email protected] / [email protected]

Low food chain species Mr Hussin bin Mat Ali [email protected]

Philippines Ms Prescilla B. Regaspi, [email protected] Ms Marygrace C. Quintero, [email protected]

Collaborating organisations

46 Aquaculture Asia Magazine News & events

Launch of VCDs on Fishery Technologies

The Fisheries College and Research Institute, a constitu- ent Institute of Tamilnadu Veterinary and Animal Sciences University, India has released two new extension VCDs on Composite Fish Culture and Preparation of Fish Pickle – a Value added fi shery product from low value fi sh. The VCD on Composite Fish Culture deals with aspects such cultur- able species, pond preparation, fertilizers and their applica- tions, stocking, feeding and transportation of fi sh fi ngerlings, water quality management, harvesting and economics. The VCD on Preparation of Fish Pickle contains information on suitable species, ingredients, steps involved in the prepara- tion of fi sh pickles, and economics. Both are 25 minutes in duration. The above VCDs are aimed at entrepreneurs interested in starting composite fi sh culture and in the commercial production of fi sh pickle using cost effective technology. The VCDs are US$20 and may also be obtained in the form of DVD for US$30, inclusive of postage and handling.To order, contact: Dr.G.Sanjeeviraj, Professor & Head, Department of Fisheries Extension, Fisheries College and Research Institute, Tamilnadu Veterinary and Animal Sciences University, Thoothukudi - 628 008, India. Email: ttn_fi [email protected] or fax: 091-461-2340574.

Proceedings of the Second International Symposium on the Management of Large Rivers for Fisheries

The proceedings of the symposium have been released in the form of a two-volume hardcover set of peer-reviewed papers. The symposium had three primary objectives: To provide a forum to review and synthesise the latest information on large rivers; to raise the political, public and scientifi c aware- ness of the importance of river systems, the living aquatic resources they support and the peoplethat depend on them; and to contribute to the better management, conservation and restoration of the living aquatic resources of large rivers.The symposium was organised in six sessions covering the status of rivers, value of river fi sheries, fi sheries ecology and con- servation, management of river fi sheries, statistics and infor- mation, and a synthesis. Contributed papers represented 96 rivers from 61 basins from all continents and climatic zones. Published by FAO and the Mekong River Commission. MRC have a reputation for producing high-quality publi- cations, and this is no exception. Excellent. Ed.

January-March 2005 47 News & events

For more events listings the NACA Events & Training page at

http://www.enaca.org/modules/extcal/

Annual Workshop and In addition to contributed posters and international trade show will be held Conference of the Australian oral presentations, there will be several simulteously. For more information, Society for Fish Biology, 11-15th keynote presentations and opportuni- including a downloadable conference July 2005 Darwin, Australia ties to discuss state of the art detection brochure, abstract submission and reg- methods. The symposium will also istration details visit the WAS website, The Australian Society for Fish offer unique opportunities to presenters http://www.was.org. Biology (ASFB) would like to invite and attendees: scientists from across Asia to par- • To learn more about the Marine and 6th Symposium on Diseases in ticipate in its annual workshop and Freshwater Toxins Task Force and Asian Aquaculture (DAA VI), 25- conference. Conveniently situating in how to contribute to this new and 28 October 2005, Colombo, Sri Australia’s northern city of Darwin, the exciting effort to foster the develop- Lanka event will be easily accessible for all. ment and validation of powerful and The theme for this year’s workshop is practical methods for toxin analysis, The theme of the sixth symposium is ‘Monitoring Fish Stocks and Aquatic and greater availability of toxin ‘Aquatic Animal Health Facing New Environments’. The conference is open standards. Challenges’. A workshop, a training to all aquatic research and management • A forum to meet with international course, an expert consultation and topics. Registrations and abstracts are members of the seafood industry, the 7th Triennial General Meeting now being accepted. Further informa- their associations, and also regula- (TGM-7) of FHS are being planned in tion: Contact gmesser@thebestevents. tory agencies. These stakehold- conjunction with DAA VI. Details will com.au or visit http://www.territorylive. ers, who are the ultimate users be made available through a dedicated com/asfb2005/. and/or benefactors of the analytical website to be launched in October. Five methodology, will also fi nd that the previous Symposia (Bali 1990, Phuket Marine and Freshwater Toxins symposium and Task Force can be 1993, Bangkok 1996, Cebu 1999 and Analysis, 11-14 April 2005, used to express their needs. Brisbane 2002), each brought together Baiona, Spain • To observe or participate in the ac- more than 200 aquatic animal health tivities of focused subgroups in the scientists, students, government re- The symposium will address new areas of saxitoxins, diarrhetic toxins, searchers and industry personnel from developments and validation efforts in yessotoxins, domoic acid, and oth- some 30 countries to discuss disease the analysis of marine and freshwater ers. Subgroups have proven to be the related problems affecting aquaculture toxins, and is held as a joint meeting most effective means of developing production and to fi nd solutions for with the AOAC Task Force on Marine methodology needs and validation them. Please visit the FHS website and Freshwater Toxins. strategies. Symposium presenters for more detailed information about Presentations will address special and attendees are welcome to attend. the society and DAA. Expressions of needs of the community from toxin For more information contact james. interest to participate or request for monitoring to new concerns in the [email protected] or visit: http:// inclusion in the mailing list may be sent intentional contamination of food and www.aoac.org/marine_toxins/task_ to Dr. Melba B. Reantaso at Melba. water. The conference venue is the force.htm. [email protected] using the subject: University of Vigo, in new on-site DAA VI. More information about conference facilities. The University, World Aquaculture 2005, 9-13 DAA VI is available for download as home to the Department of Analytical May 2005, Bali, Indonesia an attachment from: http://www.enaca. and Food Chemistry, is located near org/PDF/DAA_VI_First_Announce- Baiona and Vigo in the Galicia region It’s the biggest aquaculture conference ment.pdf of northwestern Spain. In addition to on the planet and in 2005 it will be held being the largest European producer in Bali, Indonesia. WAS 2005 will cre- of mussels, shellfi sh-rich Galicia is ate a unique opportunity to meet farm- also a very beautiful and historic area. ers, scientists and government regula- tors from every corner of the globe. An

48 Aquaculture Asia Magazine