ExoticAquaticOrganisms inAsia Proceedings of a Workshop on Introduction of Exotic Aquatic Organisms in Asia Edited by SENA S.DE SILVA / Asian Fisheries Society Special Publication No. 3 tRIfS ARCHIV i.j'ii 283 LI AIDAB CANADA r Exotic Aquatic Organisms in Asia Edited by S.S. De Silva 1989 Published by the Asian Fisheries Society in association with the International Development Research Centre of Canada and the Australian International Development Assistance Bureau Exotic Aquatic Organisms in Asia Proceedings of a Workshop on Introduction of Exotic Aquatic Organisms in Asia Edited by S.S Di SILVA 1989 Printèdin Manila, Philippines. Dc Silva, S.S., editor. 1989. Exotic aquatic organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, iS4 p. Asian Fisheries Society, Manila, Philippines. Copyright, 1989, Asian Fisheries Society, Philippines, and International Development Research Centre, Canada. Cover by: Ovidio Espiritu, Jr. ISBN 97 1-1022-53-2 Contents Foreword v Introduction vi Presidential Address vii Dr. Chua Thia Eng, President Asian Fisheries Society Address by the Chairman of the Workshop ix Dr. Sena S. De Silva Exotics - A Global Perspective with Special Reference to Finfish Introductions to Asia S.S.DeSilva Impacts of Introduced and Translocated Freshwater Fishes in Australia 7 A.H. Art hington Exotic and Translocated Freshwater Fishes in Australia 21 Ri. McKay The Status of the Exotic Aquatic Organisms in China 35 Tan Yo-Jun and Tong He-Yi Impact of Exotic Aquatic Species in Indian Waters 45 H.P.C. Shez'ty, M.C. Nandeesha andA.G. Jhingran Exotic Aquatic Species Introduction into Indonesia 57 H. Muhammad Eidman Present Status of Aquatic Organisms Introduced into Japan 63 K. Chiba, V. Taki, K. Sakai and Y. Qozeki The Status of Introduced Fish Species in Malaysia 71 K.J. Ang, R. Gopinath and T.E. Chua II' The Introduction of Exotic Aquatic Species in the Philippines 83 R.O. Juliano, R. Guerrero III and I. Ronquillo Introduction of Exotic Aquatic Species in Singapore 91 L.M. Chou and T.J. Lam Status of Introduced Species in Sri Lanka 99 S.S. De Silva Exotic Aquatic Species in Taiwan 101 I-Chiu Liao and Hsi-Chiang Liu Exotic Aquatic Species in Thailand 119 T. Piyakarnchana Australian Government Position: Introduction of Exotic Aquatic Species 125 F.B. Michaelis Recommendations of the Workshop 133 List of Participants 136 Appendices Definition of Exotics 139 Assessment of the Impact of Major Food Fish Species Introduced into Some of the Asian Countries 141 Ill. Instances of Decline/Appearance of Indigenous Species as a Possible Consequence of Introduced Fish Species 150 Ornamental Fishes 152 Existing Legislation or Code of Practices Adopted by Individual Countries in Respect of Introducing Aquatic Species 153 iv Foreword Introductions of exotic aquatic organisms have been going on worldwide for centuries. Asia, for one, has long been engaged in importations from Africa and Europe. It has likewise been an active center which has exported endemic species to other parts of the globe. Because of the increasing problems brought about by indiscriminate transfers of 'potential' species from one country to another, various national governments made steps to regulate such activities. The Code of Practice to reduce risks of introductions initially framed by the International Council for the Exploration of the Sea (ICES) was a vital step indicating worldwide concern on the effects of uncontrolled species introductions. The European Inland Fisheries Advisory Commission (EIFAC) in 1982 then organized a symposium on "Stock Enhancement in the Management of Freshwater Fisheries" and visualized an International Code of Practice for Europe. Rigid regulatory control measures were then patterned after these and employed by many developed countries. Unfortunately, the lack of strict regulatory measures in developing countries has resulted in indiscriminate introductions, some of which remain unrecorded to this day. The Workshop on the Introduction of Exotic Aquatic Organisms in Asia organized by the Asian Fisheries Society in June 19-21, 1988 in Darwin, Australia, was an initial effort of fisheries scientists in the region towards regulating exotic species introductions into Asia. We appreciate the active participation of these scientists during the workshop and the Society is grateful to the Australian International Development Assistance Bureau (AIDAB) and the International Development Research Centre (IDRC) of Canada for the funding support which contributed to the smooth and successful conduct of the workshop. It is hoped that the issues and recommendations raised in this workshop shall complement existing efforts of national governments and the Food and Agricultural Organization of the United Nations (FAQ) in developing an applicable code of ethics in the regulation of future introductions in Asia. CHUA THIA-ENG President Asian Fisheries Society V Introduction This special publication of the Asian Fisheries Society, in conjunction with the International Development Research Centre (Canada) and theAustralian International Development Assistance Bureau comprises the Proceedings of the Workshopon Exotic Aquatic Introductions into Asia, held in Darwin, Australia in June 1988. It is inevitable that all countries in the region cannot be covered ina small Workshop, primarily due to financial limitations. However, it is hoped that these Proceedings willcreate a revitalization of interest in the region on the role of exotic species and helpto address the question more scientifically and objectively when future introductionsare considered. These Proceedings should be consideredas the first of a set of documentations on this complex issue, and therefore should not be considered as a complete review. I am thankful to Mr. Jay Maclean, Secretary, Asian Fisheries Society, and Ms. ElsieTech, Executive Secretary of the Society for their help in the editing. The editingwas clone mostly when I was on an attachment to the Department of Zoology, National University of Singapore, and I am grateful to Prof. T.J. Lam, and the NUS for givingme this opportunity. Sena S. De Silva vi Address of Dr. Chua Thia-Eng President of the Asian Fisheries Society It is a pleasure and honour for me to address this important workshop on "Introduction of Exotic Species in Asia". The Asian Fisheries Society is indeed grateful to all those who have helped to make this workshop possible, especially to the Government of the Northern Territory, Australia, for hosting this workshop, the Australian International Development Assistance Bureau (AIDAB) for travel support, the International Development Research Centre (IDRC) for pre-workshop preparations and publication of workshop proceedings and other national agencies that helped to bring many of our scientists to this gathering. The contribution of these international and national agencies speaks for the importance of the subject matter that we will be discussing in the next couple of days. The issue on exotic species transfer is of international concern pertaining to the high risk of introduction of diseases, disruptive effects on aquatic communities and environment as well as the genetical degradation of host stocks. Not withstanding the above, introduction of exotic species between countries will continue to occur as it has already been doing so in the past 3 decades, closely associated with aquaculture development, the increase of aquarium fish trade and inland water body management. Asia is one of the world's active centers involved in movement of fish from one nation to another for decades without any effective regulatory control. Thus, the African cichlid, Oreochromis mossambicus, abounds in most water bodies in Asia. Since its introduction the golden snail (Ampullaria cyprinas) into the Philippines has become a nuisance to rice cultivation. The water hyacinth (Eichhornia crassipes) from South America has become a problematic aquatic macrophyte, blocking waterways in lakes, rivers and choking fish ponds. Introduced species have beneficial effects, too, especially in economic gain, to countries which badly require foreign exchange earnings and a cheap fish protein supply. In fact, many of the Chinese and Indian carps introduced into various nations in Asia have played a significant role in increasing national aquaculture production. Exotic species introduction is often initiated by fishery professionals who are either ignorant or unconcerned of the risks involved as well as by commercial enterprisesin the aquarium trade. In most countries of Asia, there are sufficient legislative measures to control importation of undesirable species. However, the inability to effectively implement legislative requirements has given rise to easy entry of exotic species in the region. Public awareness and strict implementation of regulatory measures in North America have helped in curbing unregulated introductions. The establishment of mechanisms governing the introduction of exotic species through international agreements like the "Code of practice to reduce the risks of adverse effects arising from the introduction of non-indigenous species" adopted by the International Council for the Exploration of the Sea (ICES) and the European Inland Fisheries Advisory Commission (ETFAC) represent the regional efforts in Europe. In Asia, the Indo-Pacific Fisheries Council (IPFC) has expressed concern over past and present introductions but places emphasis on the collection and exchange of information. Regulatory measures are left to individual country's legislation.