The International Development Research Centre is a public corporation created by the Parliament of Canada in 1970 to support research designed to adapt science and technology to the needs of developing countries. The Centre's activity is concentrated in five sectors: agriculture, food and nutri­ tion sciences; health sciences; information sciences; social sciences; and communications. I DRC is financed solely by the Parliament of Canada; its policies, however, are set by an international Board of Governors. The Centre's headquarters are in Ottawa, Canada. Regional offices are located in Africa, Asia, Latin America, and the Middle East. © International Development Research Centre 1982 Postal Address: Box 8500, Ottawa, Canada K 1G 3 H9 Head Office: 60 Queen Street, Ottawa, Canada Davy, F.B. Graham, M. IDRC. Asia Regional Office, Singapore SG IDRC-200e Bivalve culture in Asia and the Pacific: proceedings of a workshop held in Singapore, 16-19 February 1982. Ottawa, Ont., IDRC, 1982. 90 p.: ill. /Oyster culture/, /molluscs;, /fishery research / , /Asia/, I Papua New Guinea/, /Fiji/, /French Polynesia/ - /technical aspects; /fish production/, /research and development/, /conference report/, /list of participants/, / IDRC mentioned , bibliography. UDC: 639.4 (5.9) ISBN: 0-88936-343-9 Microfiche edition available II existe egalement une editionfranraise de cette publication. La edici6n espanola de es ta publicaci6n tambien se encuentra disponible. IDRC-200e BIVALVE CuLTUREIN As1A AND THE PACIFIC PROCEEDINGS OF A WORKSHOP HELD IN SINGAPORE 16-19 FEBRUARY 1982 EDITORS: F. BRIAN DAVY AND MICHAEL GRAHAM RESUME Du 16 au 19 fevrier 1982, sous l'egide du departement de production primaire du ministere du developpement national et du Centre de recherches pour le developpement international, s'est tenu a Singapour un collogue sur Jes modes d'elevage et l'etat actuel de la culture des lamellibranches - huitres, moules, clovisses, palourdes - en vue d'etablir un plan d'avenir dans ce domaine. Le collogue a reuni trente-cinq participants de l'ASEAN (Association des pays du sud-est asiatique) ainsi que des delegues de Bangladesh, Burma, Chine, Fiji, Papouasie Nouvelle-Guinee, Sri Lanka, Tahiti et du Canada. On trouve des bivalves en abondance sur Jes cotes de presque tous Jes pays, ou on Jes recolte comme aliment de subsistance. Mais quelques pays ont commence a Jes cultiver et ils esperent que des recherches appropriees leur permettront de tripler la production. II a surtout ete question, au cours de la reunion, des possibilites d'adapter Jes techniques de culture a l'environnement des pays interesses. Les participants ont ete invites a visiter Jes elevages de moules suspend us a des radeaux et le systeme de traitement mis au point par le departement de production primaire de Singapour. Les domaines de recherche prioritaires determines par Jes participants sont: la formation aux methodes de culture, un approvisionnement de naissain ameliore, des criteres de selection de site mieux definis, des etudes economiques plus detaillees, l'eta­ blissement de normes de salubrite des bivalves destines a la consommation humaine et des mecanismes permettant l'echange d'information technique sur la recherche relative aux lamellibranches. RESUMEN Del 16 al 19 de febrero de 1982 tuvo lugar en Singapur un seminario auspiciado por el Departamento de Producci6n Primaria del Ministerio de Desarrollo Nacional de Sin­ gapur y el Centro Internacional de Investigaciones para el Desarrollo, destinado a examinar los metodos y el estado actual del cultivo de bivalvos -ostras, mejillones, almejas y coquinas- en Asia y el Pacifico y hacer recomendaciones sobre programas y actividades futuras en este campo. El seminario conto con 35 participantes de las naciones de ASEAN (Asociaci6n de Naciones del Sudeste Asiatico), asi como de Bangladesh, Birmania, China, Fiji, India, Papua Nueva Guinea, Sri Lanka, Tahiti y Canada. La mayoria de estos paises tienen bivalvos abundantes en las areas costeras, donde son recogidos para consumo local ode subsistencia. Varios de ellos han iniciado el cultivo artificial y se calcula que, con investigaci6n adecuada, las tecnicas de cultivo pueden triplicar la producci6n. El seminario hizo enfasis en la adaptaci6n de las tecnicas actuales de cultivo de bivalvos a las condiciones locales de los paises circunvecinos con miras a aumentar la producci6n. Los participantes tuvieron oportunidad de visitar el sistema de cultivo en balsas y el equipo postcosecha respectivo para mejillones, desarrollado por el Departa­ mento de Producci6n Primaria de Singapur. Entre las prioridades identificadas esta la capacitaci6n en tecnicas de cultivo, la mejora en el suministro de semilla y en los criterios de selecci6n de sitios de cultivo, la necesidad de estudios econ6micos detallados y de normas sobre calidad sanitaria de los bivalvos de consumo humano, asi como de medios para intercambiar informaci6n sobre investigaci6n en bivalvos. CONTENTS Foreword ........................................................ 5 Workshop Summary Plans and Recommendations. 8 Sessions ...................................................... 9 Country Reports Bangladesh ................................................... 20 China ........................................................ 21 Fiji .......................................................... 29 French Polynesia .............................................. 31 India ........................................................ 34 Indonesia .................................................... 44 Malaysia ..................................................... 47 Papua New Guinea ............................................ 53 Philippines ................................................... 55 Singapore .................................................... 69 Sri Lanka .................................................... 72 Thailand ..................................................... 73 Appendices 1. Participants ................................................ 80 2. Papers Submitted at the Workshop ............................ 82 3. Bibliography ............................................... 83 3 FOREWORD Bivalves such as oysters, mussels, clams, and cockles are widely distributed throughout tropical waters. Typically, they occur in mangrove areas or in coastal regions where, following a brief period of juvenile motility, they attach to rocks, wharves, fish traps, and other static objects. In many countries of Asia and the Pacific, it is a tradition to collect the naturally occurring molluscs as a cheap source of food. Once upon a time, molluscs were a cheap food for poor people in many European countries. Now, they are expensive, luxury items in Europe and North America. In the tropics, however, they can be harvested from the wild or cultivated relatively inexpensively. Consequently the interest in mollusc culture is growing rapidly in a number of countries. It has been demonstrated in several tropical regions that it is both techni­ cally and economically feasible to culture bivalves to produce a marketable product in high yield in less than a year. Reported yields of green mussels, grown on ropes suspended from rafts, for 5 months are 10-12 kg/ m of rope in a number of countries in the region. The yield of nutritionally high-quality protein per hectare of surface water far exceeds the protein that could be produced on a hectare of land by any known terrestrial plant or animal. Since 1973, the Agriculture, Food and Nutrition Sciences (AFNS) Division of the International Development Research Centre (IDRC) has supported bivalve-culture research projects in several tropical countries. Projects in Asia, Africa, and the Caribbean have studied oysters and mussels; other projects in Latin America have examined oysters, mussels, and cockles. In recognition of the growing interest, a regional meeting was convened to review past and current work in bivalve culture in Asia and the Pacific and to attempt to establish regional priorities for future research. The emphasis of this meeting, held in Singapore from 16 to 19 February 1982, was on bivalves for human food. A mussel-culture raft system, developed by the Singapore Primary Production Department in Changi Strait, was used as a valuable focus for demonstration. The culture of molluscs such as pearl oysters, windowpane oysters, and clams - used in the shellcraft industries - was also discussed because similar culture systems can be used for these economically attractive species. The working meeting reviewed culture practices, postharvest handling, the economics of mollusc management, and future research needs, with some lesser reference being made to the taxonomy of bivalves. The names and pattern of distribution of known species are listed in Table A; throughout the meeting, common names were used where taxonomic identification was not available. Several countries have demonstrated that cultured bivalves will grow more quickly than those that occur naturally. The increase in yield is substantial and offers an attractive opportunity for aquaculturalists, fisheries research and development organizations throughout the Asian region. Some of the con- 5 6 BIVALVECULTURE straints encountered in bivalve culture appear in the status reports presented by participants at the meeting and edited for inclusion in this volume. For some species (e.g., cockles, Anadara granosa), further extensive culture research appears unnecessary, as the present system of relaying or sowing seed cockles appears to