ISSN: 1681-7613 Proceedings of the 7th Technical Symposium on Mekong Fisheries Ubon Ratchathani, Thailand 15 th - 17th November 2005 MRC Conference Series No6 Mekong River Commission Vientiane, Lao PDR 7th Technical Symposium on Mekong Fisheries Symposium Proceedings 15th -17th November 2005 Editors: T.J. Burnhill and T.J. Warren Suggested citation: Burnhill T.J. and Warren T.J. (eds) 2006. Proceedings of the 7th Technical Symposium on Mekong Fisheries, 15th – 17th November 2005. MRC Conference Series No. 6. Mekong River Commission, Vientiane. 324 pp. ISSN: 1681-7613 The opinions and interpretations expressed within are those of the authors and do not necessarily refl ect the views of the Mekong River Commission © Mekong River Commission P.O.Box 6101, 184a Fa Ngoum Road Ban Sithane Neua, Sikhottabong Vientiane, Lao PDR Telephone: (856-21) 263263. Fax: (856-21) 263264 E-mail: [email protected] Website: www.mrcmekong.org ii Foreword The Annual Technical Symposium on Mekong Fisheries has become a central element of the MRC’s Fisheries Programme. The 2005 symposium, which was held in Ubon Ratchathani, Thailand, was the seventh the Programme has hosted since 1998. Each year the symposium attracts a larger audience and an increasing number of speakers. The papers included in this volume of proceedings cover subjects as diverse as prawn fi sheries in southeast Cambodia and fi sheries co-management in the Central Highlands of Viet Nam. They represent the work of over a hundred fi sheries experts from the four MRC member countries and from as far afi eld as Australia and Sweden. The contributions from overseas are very welcome as they are clear indication of the international recognition the symposium now receives. However, we must not forget the primary reasons for holding the symposium. These are to provide a forum in which fi sheries experts from across the region can meet to present and discuss their research and, most importantly, an occasion for young scientists working in the various riparian line agencies to present the results of their efforts to their peers and to an international audience. Publishing is a vital part of research, for no matter how good or important the research, results have little value unless they are made available for managers and other researchers to use and develop. Furthermore, the process of preparing work for presentation and publication can only improve the quality of research, because it demands discipline of purpose and clarity of thought. The thirty- two papers in these proceedings have, no doubt, cost each of the authors a great deal in both time and energy, and they are all to be applauded warmly for their efforts. The standard of the papers is a testimony to their efforts, and it is very encouraging to see the quality of the submissions improving year-after-year. This is a trend that I am confi dent will continue through future technical symposiums. The fi sheries of the Mekong River are a vital factor in the lives and livelihoods of millions of people who live in the riparian countries. Sustaining these fi sheries requires improved management based on increased knowledge. The body of knowledge included in these proceedings is an important contribution to ensuring that the fi sheries of the Mekong River system continue to provide employment, nutrition and income for millions of people in the basin. Dr Olivier Cogels Chief Executive Offi cer Mekong River Commission Secretariat October 2006 iii Proceedings of 7th Technical Symposium on Mekong Fisheries Page iv Ubon Ratchathani, Thailand, 15th - 17th November 2005 Contents Foreword ............................................................................................................................... iii Section 1. Assessment of Mekong Capture Fisheries The Dai Bongkong fi shery for giant river prawns, Macrobrachium rosenbergii, in southeastern Cambodia .............................................................................................................. 3 Standing crop and fi sh species association in Cambodian fl oodplains ....................................33 Monitoring of fi sh markets in Vientiane and Luang Prabang Province, Lao PDR, using logbooks ................................................................................................................................... 47 Trial monitoring of fi shers in the Mekong Delta, Viet Nam ....................................................61 Monitoring of fi sh larvae during the annual fl ood of the Mekong and Bassac rivers, Mekong Delta, Viet Nam ....................................................................................................................... 71 Section 2. Management of River and Reservoir Fisheries Streamlining community fi sheries plans into commune plans, Cambodia ..............................91 Nursing of silver barb (Puntius gonionotus) in hapas at Huay Siet Reservior Lao PDR ......105 Gender in fi sheries management in the Lower Songkhram River Basin, in the northeast of Thailand ..................................................................................................................................111 Fisheries co-management in Lower Songkhram River Basin: problems and challenges .....121 Strengthening co-management of water resources for rice-shrimp farming in Soc Trang Province —Viet Nam .............................................................................................................. 127 Is there fi sheries co-management in Daklak province, Central Highlands of Viet Nam? ..... 147 Section 3. Aquaculture of Indigenous Mekong Species Economic evaluation of small-scale aquaculture of indigenous fi sh in Cambodia ............... 161 Artifi cial reproduction of the carp Cirrhinus microlepis performed in the south of Laos by using LHRHa implant ............................................................................................................ 171 Reproduction and nursing of Cirrhinus molitorella in a small fi sh farm in Luang Prabang Province, Lao PDR ................................................................................................................ 197 Preservation of Cirrhinus microlepis sperm .......................................................................... 205 Culture of Red-tail Mystus, Hemibagrus wyckioides, in earthen ponds with different stocking densities ................................................................................................................................. 213 Preliminary results of domestication of Pangasius krempfi .................................................. 217 Section 4. External papers Surveys of native freshwater fi shes in Surin province, Thailand .......................................... 225 Fish passage and fi shways in the Mekong Basin: getting past the barriers. ..........................237 Identifying stock structure of two Henicorhynchus species in the Mekong River using mitochondrial DNA ............................................................................................................... 253 Proceedings of 7th Technical Symposium on Mekong Fisheries Ubon Ratchathani, Thailand, 15th - 17th November 2005 Page v Section 5. Poster presentations Effectiveness of mobile and permanent hatchery practised by community fi sheries ............267 Brooder rearing of small-scale mud carp, Cirrhinus microlepis (Sauvage, 1878) with different commercial feeds ................................................................................................................... 273 Comparison of three feeding formulas with Pangasius hypophthalmus at Ban Hat Station, Khong District, Champassak Province, Lao PDR ................................................................275 Fish larvae during the dry season in the Tonle Sap River .................................................... 283 Drift of fi sh fry and larvae in fi ve large tributaries of the Tonle Sap-Great Lake system in Cambodia ............................................................................................................................... 289 Monitoring river fi shers along the Mekong River in Lao PDR .............................................295 Adaptive community fi sheries management in Cambodia what indicators? .........................301 Established process and activities of fi sheries co-management model in Lak Lake, Daklak Province, Viet Nam ................................................................................................................ 311 Local ecological knowledge and customary resource tenure for a Macrobrachium fi shery on the Nam Khan ........................................................................................................................ 321 Proceedings of 7th Technical Symposium on Mekong Fisheries Page vi Ubon Ratchathani, Thailand, 15th - 17th November 2005 Section 1. Assessment of Mekong Capture Fisheries Proceedings of 7th Technical Symposium on Mekong Fisheries Ubon Ratchathani, Thailand, 15th - 17the November 2005 Page 1 Proceedings of 7th Technical Symposium on Mekong Fisheries Page 2 Ubon Ratchathani, Thailand, 15th - 17the November 2005 The Dai Bongkong fi shery for giant river prawns, Macrobrachium rosenbergii, in southeastern Cambodia NGOR Pengbun*, AUN Sinath and Kent G. HORTLE Assessment of Mekong Capture Fisheries Component, Mekong River Commission; Department of Fisheries, Inland Fisheries Research and Development Institute ABSTRACT Prey Veng Province is located in the Mekong Delta region of Southeastern Cambodia. In this lowland area,