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. The main purpose of this workshop is to objectively review the impacts of species transfer in Asia taking into consideration the meager socioeconomic conditions of Asian nations and to explore appropriate measures by which exotic species introduction can be best regulated. One immediate impact of this workshop is a greater concern of fishery professionals like us who can vii help to promote national awareness of the issue and help develop appropriate strategiesto minimize the adverse effects of exotic species transfer. In closing, I wish to thank the local secretariat, in particular Director Darryl Grey, for his excellent local arrangements and time and effort put into the preparation of this workshop. Thank you. Address by the Chairman of the Workshop

We of the Asian Fisheries Society are grateful to the Australian International Development Assistance Bureau for making this workshop possible. I consider it a deep honour to be invited to Chair this workshop and wish to express my gratitude to my fellow Councillors for bestowing this privilege and take this opportunity to welcome all the participants to this workshop. In keeping with one of the main objectives of the Asian Fisheries Society, to address key issues pertaining to fisheries in the region, the Council atits Second Meeting in 1984 unanimously decided that the Introduction of Aquatic Organisms into the region needed careful consideration. We were aware that this issue was also being addressed by some international organizations amongstothers, and the American FisheriesSociety.Inspiteof these considerations the Society felt a need to consider this issue; complex as it is from an Asian context where the the socio-economic factors cannot be ignored and or separated from the fisheries issues in general. Initially, four Objectives for the Workshop were identified:

address the issue of aquatic introductions in the region,

evaluate the pros and cons of introductions hitherto made in the region,

develop guidelines/a code of ethics for future introductions, and

issue a policy statement on future introductions.

It is unlikely that we would be able to fulfill our objectives within the next three days. I consider this workshop as the first step in the direction of achieving our objectives. In order to do so we will have to address our minds to a few key points: Do we have sufficient information/knowledge of the situation in each of the countries in the region - if so how do we proceed to collect this information, especially that in the 'grey literature'

Do we need to develop protocols for consideration by Governments in the region, and if so what criteria should we use: should they take into account the socio- economic factors, etc.

Are thererecent examples from theregionor elsewhere on proposed introductions that impel us to think afresh?

Undoubtedly all of us would agree that we should not adopt, clause to clause, what has been recommended as suitable for Northern America, Europe and or for that matter mainland Australia. This is not because we want to be different but such a course of action would be self defeating. If we were to do the former there would not have been a need to come to this lovely city, Darwin. Equally, we have a lot to gain from their experiences.

ix Conditions in Europe and North America are not comparable to that of ours ir the region. Here, I do not mean in a climatological sense but in the context of the numbe: of species involved, complexity of the habitats, heterogeneity of the flora and fauna, anl the gross beneficial effects of some introductions that have contributed to the animal protein supply. Some of the socio-economic benefits of introductions are not totally quantifiable but they certainly cannot and should not be ignored. Ladies and Gentlemen with these few remarks, which I hope would help us to focus at some of our deliberations, I wish to commence the proceedings. We should all bear in mind that the deliberations of the next three days will direct the Society's future course of actioa in dealing with this very complex issue. Finally, it is my duty to express our gratitude and appreciation to the local organizers Mr. Darryl Grey and his team, for their excellent arrangements. Thank you.

Sena S. De Silva

x Exotics-A Global Perspective with Special Reference to Finfish Introductions to Asia

SENA S. DE SILVA Departments of Fisheries Biology and Zoology University of Ruhuna Matara, Sri Lanka

De Silva, S.S. 1989. Exotics - a global perspective with special reference to finfish introductions to Asia, p. 1-6. In S.S. Dc Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines.

The need for a fresh evaluation of the definition of 'exotics' is pointed out. The global transfer of finfish species is summarized. Those species which have been transferred across all five continents are considered as 'global' and number 15, of which six have originated from Asia. Recent controversies on introductions are briefly pointed out and the need for detailed scientific evaluation prior to deciding on an introduction, based on recent recommendations from Asia, is focused on. Asia in general, has suffered comparatively limited damage as a result of introductions. In particular the number of native species lost or endangered in the region and directly attributable to an exotic is scanty.

Exotic(s) and introduction(s) are terms used synonymously to define the transfer of live organisms from one country to another. With respect to aquatic organisms more refined definitions have been attempted: for example, that by Shafland and Lewis(1984). These authors defined an exotic as an organism whose entire range is outside the country to which it is introduced. In essence all definitions encompass into them, the concept of country boundaries. If one were to extend this further an introduction of a species between some of the Indonesian islands, even across the accepted zoogeographical boundaries such as Wallace's or Weber's lines, would not be tantamount to an introduction and the species transferred will not be classified as an exotic: this reference is not hypothetical. In essence the political boundaries, which have no real biological basis or validity should not be the criterion for defining an exotic and or an introduction but the zoogeographical boundaries of the organisms. In the context of an acceptance of the above definition a revision of the status of introductions in the world, and in Asia in particular is needed.

Inland Fish Species Transfers - Global Status

The global status of the international transfers upto 1981 was reviewed by Welcomme (1981). A summary of the transfers made globally, is given in Table 1. A total of 168 finfish species belonging to 33 families have been introduced either deliberately or accidentally out of their natural distribution range. In this analysis the traditional geographical boundaries were

1 2 taken as the basis for the introductions. This number is less than that reported later by Welconime (1984) when he observed that 163 species have moved to 120 countries of which 42% have established successfully. The two major families which have been subjected to such transfers beyond their natural range are the Cichlidae and the Cyprinidae, of which 36 and 37 species have been transferred from their natural ranges respectively. Transfers across all continents which could be considered as global introductions number only 15 species. Of these six have originated from Asia and are all Cyprinids- primarily the Chinese and Indian major carps. A total of 35 species have been transferred from Asia and 22 into Asia, of which 6 have been introduced into Oceania. According to Jhingran and Gopalakrishnan (1974) however, 24 species have been introduced into Southeast Asia. The reasons for the introduction/transfer of fish as well as other aquatic organisms beyond their normal range of distribution are many. Welcomme (1981) recognized three clear phases and reasons for introduction with respect to freshwater fish;

Phase I period equivalent to the Middle Ages in Europe- diffusion of a limited number of species throughout Europe and Asia. Phase II middle of the nineteenth century to about 1940- for sport and for sentimental reasons e.g., the spread of Salmonids from Europe into Asia, and

Phase III : 1940 to date - for aquaculture and ornamental trade e.g., the spread of Chinese and Indian major carps.

In the recent years the question of introductions/transfersacross countries has been receiving increasing attention, in particular piscine introductions. The status of introductions into America and Oceania were considered in detail by Courtenay and Stauffer (1984) and includeda protocol for evaluating proposed exotic fish introductions into the United States. In Europe, the question was addressed by the European Inland Fisheries Advisory Commission (EIPAC) of the Food and Agriculture Organization, and five specific protocols were evolved for the inspection of molluscs, crustaceans, marine fish, salmonid fish and molluscan hatcheries (EIFAC/CECPI 1984). An attempt was also made to develop an international policy for the reduction of risks and adverse effects arising from introductions. To meet this end it was felt that two levels of documentation were necessary.

A code of Practice- a general guideline and statement of policy which can supplement local legislation, and

Protocols - oriented check lists for implementation of the code of pracl;ice. In the development of an international policy and a code of practice for effecting introductions one has to take into consideration the sentiments expressed by neighbouring countries, even if they are widely separated. It is in this perspective that Coates (1987) dealt with the introductions into Papua New Guinea. 3

Table 1. Summary of introductions of fish species in the world (derived from Welcomme 1981). Columns ito5in order are, number of species introduced into region beyond its native distribution range; global introductions where the species has been introduced into at least 4 continents; introduced from Asia; introduced into Asia and inter-Asian introductions. As-refers to originating from Asia; 'Oc' refers to Oceania.

Family 1 2 3 4 5

ACIPENSERIDAE 2 2 ANABANTIDAE 6 5 ANGUILUDAE 3 1 2 ATHERIMDAE 1 1 BAGRIDAE 1 CENTRARCHIDAE 12 1 2 CENTROPOMIDAE 1 CHANNIDAE 1 CHANTDAE I CICHLIDAE 36 4 1 3;20c CLARIIDAE 2 1 CLUPEIDAE 2 COBITIDAE 1 1 COREGONTDAE 3 CYPRJMDAE 37 6As 6 i;20c 12 CYPRINODONTIDAE 1 ELEOTRIDAE 2 1 ERYTHRINIDAE 1 ESOCIDAE 2 2 GOBIIDAE 3 3 ICTALURIDAE 3 1;lOc LORICARIIDAE 1 ORYZIATIDAE 1 1 OSMERIDAE 1 1 OSPHRONEMIDAE 4 2 OSTEOGLOSSIDAE 2 PERCICHTHYIDAE 1 PERCIDAE 3 1 POECILIDAE 12 1 1 3:lOc SALMONTDAE 18 3 6 1: lOc SCIAENTDAE 1 1 SILURTDAE 1 UMBRIDAE 2

Controversies

When compared to the information available on finfish that on other aquatic organisms is scanty. Hitherto there had been no attempts to document such introductions either globally or regionally, even though very detrimental effects have been recorded with respect to some. A case in point is the introduction of the water fern Salvinia into Asia, which has had the most negative impact brought about by an exotic animal or plant (Bhukaswan 1980). On the other hand, with respect to finfish species the status of individual introductions have been assessed and views on their beneficial or harmful effects remain controversial. In this controversy Oreochromis mossambicus (Peters), the aquatic chicken of the 1960's (Ling 1977) is now considered a nuisance species, globally (Welcomme 1984) except perhaps in Sri Lanka (De Silva 1985; 1987) and in Papua New Guinea (West and Glucksman 1967; Coates 1985). Of course in hind sight one could suggest that the results could have been better if O.niloticus was introduced. During the 50's and early 60's O.niloticus was relatively unknown and O.mossambicus was the choice species. In these countries this species remains the backbone of an important artisanal fishery and therefore a source of protein for the poor, andthere are no reports on environmental degradation caused by this species.Comparable controversies exist 4 with respect to other introductions. For example the introduction of Lates niloticus into Lake Victoria was hailed as a disaster by some (Barel et al. 1985; Payne 1987) but its introduction into Lake Kioga is considered as a success; as much as that of Limnothrissa miodon into Lakes Kivu and Kariba (Eccles 1985). A similar debate exists with respect to the introduction of Sarotherodon aureus into Lake Kinneret (Gophen et al. 1983). The above examples point out that the lack of specific criteria and/or adoption of different standards in the assessment of the role of an exotic, and focus on the need to establish criteria for evaluating the impact of an exotic. The evolution of such a scheme for the evaltation of the impact of exotics will not have a direct bearing on the introductions made hithcrto but will permit the adoption of a more rational and an objective approach for envisaged introductions. The system or scale that is to be devised should not only take into consideration the biological and ecological impact of the introductions but an equal weightage should also be givento the sociological impact. Sociological impact is not an easily quantifiable parameter. In the present context it would mean whether the introductions have resulted in a significant contribution to the protein supply to the poorer people in an area and/or whether a significant number of job opportunities have been created or lost as a result of the introduction and the like. Reported detrimental effects as a result of piscine introductions into Asia,apart from the numerous parasites associated with the introductions, are rare and far apart; it has never reached the controversial stage as for example that associated with the Lates niloticus introduction into Lake Victoria in Africa (Bare! et al. 1985; Payne 1987). However, in Asiaaso the near extinction of the endemic small goby, sinarapan, Mistichthys luzonensis (Smith) from Lake Buhi is partly attributed to the introduction of 0. mossambicus (Baluyut 1983). Similarlythe introduction of two gobiids into Lake Lanao is supposed to have influenced its nativecyprinid flock consisting of about 20 species of Barbus (Frey 1969). Asia hasa paucity of lakes. Hence, there is an equivalent paucity of species flocks comparable to those of the African Great Lakes. In this context all efforts must be made to preserve this minuscule number ofspec es flocks in Asia. The global parasitic introductions associated with the piscine introductions have been reviewed by Hoffman and Schubert (1984). Asia contributed its shareto the rest of the continents and likewise received its share from elsewhere. It remainsa miraclthat these accidental introductions have not reached epidemic levels, except invery rare and isolated instances. Even human pathogens are involved; for example, Schistosoma mansoniwas transferred to Hong Kong in 1973-1974 in infected snails from South America (Biophalaria straminea) contaminated with imported water plants for aquaria (Meier-Brook 1975). All fish trematodes and cestodes require intermediate hosts; digenean trematodesa molluscan host, and cestodes one or more intermediate hosts. Asa result of these requirements the chances of relocation of parasitic species and their spreadingare limited. In spite of these requirements some parasites have been transferred. A case in point is the inter-continental and intra-Asian relocation of the cestode Bothriocephalus opsarichthydis (=B.go wkengensis) associated with the introduction of grass carp, initially from the Amur river stocks and later from elsewhere. 5

Decision for Effecting Introductions

Very often decisions and or recommendations for introductions aremade with a view to increasing the yield but on relatively meagre and often onless than adequate scientific knowledge. Turner (1982) advocated the introduction of zooplanktivorousclupeid Limnothrissa miodon into Lake Malai because he considered it to be a moreefficient zooplankton predator than cyprinids and or other zooplanktivores found in Lake Malai.This view has been contested (Eccies 1985; McKaye et al.1985). Eccles (1985) has attempted to show that Turner's conclusions were based on temperate examples and comparisons of lakeswith wide differences in morphometry, climatic and chemical factors. Eccles (1985)pointed out that rehabilitation (social) of the existing fishery could be more cost effective andunlikely to have any deleterious effects on the lake and will result in an equally higher yield. In Asia, Soemarwoto and Costa-Pierce (1987) recommended theintroduction of the clupeid Corica goniognathous from Thailand to fill the supposedly vacantpelagic, zooplankton feeding niche in the Jatilnuhur reservoir in the Indonesian island of Java. Laterit transpired that the species referred to is Clupeichthys aesarnensis (Costa-Pierce 1988)and that this species is endemic to the Mekong system. This goes to show thatenthusiasm and emotions seem to override scientific knowledge, which could be detrimental to the fishery aswell as flora and fauna in the future. The two instances cited here also lead to the broad question ofutilization of introductions to fill vacant niches in lacustrine waters. Admittedly, there areinstances where such introductions as in the case of Lake Kariba,have been overtly successful. Asia has a paucity of natural lakes and consequently a poor lacustrine fish fauna (Fernando and Holcik1982). There is increasing evidence that these artificial, lacustrine bodies get colonizedby suitable indigenous riverine species such as by the freshwater clupeid in the case ofUbolratna in Thailand (Costa-Pierce 1988) and by indigenous cyprinids in the case of reservoirs in SriLanka (De Silva and Sirisena 1987), which could support profitable fisheries. It is apparent that at present most introductions are donewith care and lot of scrutiny; but can we be satisfied? Aspointed out by Pillay (1977) the era of haphazard and unplanned introductions is hopefully over. However, it is important to take into accountthat there has been a general degradation of thequality and quantity of the natural habitats of most aquatic organisms and more so of those species endemic to aparticular region - an unavoidable consequence of development and humanpopulation growth. It is therefore, important to take such indirect factors also into account when planning aquaticintroductions; should or should not the need for conservation of native species and fisheries beweighed against the development benefits of improved fish stocks? It is in this context that itwould be desirable to develop a code of practice for aquatic introductions into Asia and notadopt those evolved elsewhere in their entireity.

References

Baluyut, E.A. 1983. Stocking and introduction of fish in lakes and reservoirs in the ASEANcountries. FAQ Fisheries Technical Paper 236: 82p. Barel, C.D.N. et al. 1985. Destruction of Fisheries in Africa's lakes. Nature 315 (2):19-20. Bhukaswan, T. 1980. Management of Asian reservoirs fisheries. FAQ Fisheries TechnicalPaper 207, 69 p. Coates, D. 1985. Fish yield estimates for the Sepik river, Papua, New Guinea, alarge flood plain system east of "Wallace's line. Journal of Fish Biology 27: 431-443. Coates, D. 1987. Consideration of fish introductions to the Sepik River, Papua NewGuinea. Aquaculture and Fisheries Management 19: 231-241. 6

Costa-Pierce, B. 1988. Study mission to Northeast Thailand for assessment ofa pelagic freshwater sardine Cu1peihhys aesarnen.ris. IOEIICLARM, 63 p. (mimeo). Courtenay, W.R. and LR. Stauffer. 1984. Distribution, biology and management of exotic fishes. John Hopkins University, Baltimore, 430p. De Silva, S.S 1985. Status of the introduced cichlid Sarotherodon mossambicis (Peters) in the reservoirfishery of Sri Larka: a management strategy and ecological implications. Aquaculture and Fisheries Management 16: 91-102. De Silva, S.S. 1987. Impact of exotics on the inland fishery resources of Sri Lanka. Arch iv fur Hydrobiologiebeihft, Ergebni:;se der Limnologie 28: 273-293. De Silva, S.S. and H.K.G. Sirisena. 1987. New fish resources of reservoirs in Sri Lanka: Feasibilityof introductions of a subsidiary gill net fishery for minor cyprinids. Fisheries Research 6: 17-34. Eccles, D.H. 1985. Lake flies and sardines - a cautionary note. Biological Conservation 33: 305-333. EIFAC/CECPI 1984. Report of the EIFAC working party on stock enhancement, EIFAC TechnicalPaper 44: 22 p. Femando, C.H. and J. Holcik. 1982. The nature of fish communities:a factor influencing the fishery potential of tropical lakes and reservoirs. Hydrobiologia 97: 127-140. Frey, D.G. 1969. A limnological reconnaissance of Lake Lanao, Verhein IntemationalVerhein Theoretical Agnew Limnologie 15: 112-127. Gophen, M., R.W. Drenner and G.L. Vinyard. 1983. Cichlid stocking and the decline of the Galilee SaintPeter's fish (Sarothe -odon galilaeus) in Lake Kinneret, Israel, Canadian Journal of Fisheries and Aquatic Science 40: 983 -986. Hofman, G.L. and G. Schubert. 1984. Some parasites of exotic fishes,p. 233-261. In W.R. Courtenay and R. Stauffer (eds.) Distribution, biology and management of exotic fishes. John Hopkins University, Baltimore. Jhingran, V.C. and V. Gopalakrishnan. 1974. Catalogue of cultivated aquatic organisms. FAO TechnicalPaper, 130, 83 p. Ling, SW. 1977. Aquaculture in Southeast Asia. A historical overview. Washington Sea Grant Publication,108 p. McKay, K.R., R.D. Makwinja, W.M. Menyani and O.K. Mhone. 1985. On the possible introductionof non-indigenous zooplankton-fishes into Lake Malawi, Africa, Biological Conservation 33: 289-307. Meier-Brook, C. 1975. A snail intemiediate host Schutosoma mansoni introducedto Hong Kong. WHO/SCHISTO/85: 37 p. Payne, I. 1987. A Lake perched on piscine peril. New Scientist 1575: 50-54. Pillay, T.V.R. 1977. Planning of aquaculture development. Fishing News (Books) Ltd., Surrey,England, 71 p. Shafland, P.L. and W.M. Lewis. 1984. Terminology associated with introduced organisms. Fisheries9: 17-18. Soemarwotto, 0. and B. Costa-Pierce (undated). Importation of a pelagic freshwater sardine, Coricagoniognathus to IndoneSian reservoirs for fisheries enhancement (mimeoed document). Tumer, J.L. 1982. Lake flies, water fleas and sardines. FAO Technical Report 1: 165-173. Welcomme, R.L. 1981. Register of international transfers of inland fish species. FAO Fisheries TechnicalPaper 213: 120 p. Welcomme, R.L. 1984. International transfers of inland fish species,p. 22-40. In W.R. Courtenay and J.R. Stauffer (eds.) Dütribution, Biology and management of Exotic Species. The John Hopkins University Press, Baltimore. West, G.J. and J. Glucksman. 1976. Introduction and distribution of exotic fish in Papua NewGuinea. Papua New Guinea Agricultural Journal 27: 19-48. Impacts of Introducedand Translocated Freshwater Fishes inAustralia

A.H. ARTHINGTON Center for Catchment and In-st ream Research Division of Australian Environmental Studies Griffith University Nathan, Queensland 4111 Australia

Arthington, A.H. 1989. Impacts of introduced and translocated freshwater fishes inAustralia, p. 7-20. In S.S. Dc Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction ofExotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines.

Australian inland waters have been successfully colonised by 19 freshwater speciesintroduced to the continent, including 5 salmonids, a percid, 5 cyprinids, 6 poediiids and 3 cichlids. Some of theseintroductions have been beneficial but the aim of this chapter is to review the ecological consequences of fish introductions, bothplanned and unintentional, in temis of possible adverse impacts on freshwater biota and ecosystems.Such impacts may include hybridisation between species, sub-species and genetic strains, habitat and Water quality alterations, competition, predationand the introduction of parasites and diseases. An account of the translocation of four endemic Australian fishes intoLake Eacham, Queensland is also included because these translocations appear to have caused the extinction of theendemic rainbowfish unique to the lake, chiefly as a result of predation. Conspicuous gaps in knowledge ofintroduced species in Australia and research priorities are highlighted. The final section outlines areas of ecological theory that mayassist in predicting the impacts of species introductions, i.e., the theosy of island biogeography, the concept of limiting similarityand the analysis of food webs.

Australian inland waters have been successfully colonized by 19freshwater fish species introduced to the continent, including 5 salmonids, a percid, 4cyprinids, 6 poeciliids and 3 cichlids (Table 1). There is also some slender evidence thatreproducing populations of two other species occur in Australian waters. The Jack Dempseycichlid, Cichiasoma octofasciatum (Regan), is quite abundant in the cooling pondage of Hazeiwood powerstation near Morwell, Victoria (Cadwallader et al. 1980) but it is not certain thatthis species breeds there. The weather bach, Mis gurnus anguillicaudatus, has also been reported tobreed in Australian waters (McKay, pers. comm.). Several recent reviews have summarized the origins anddistribution of introduced species in Australia, their effects on aquatic ecosystems,especially impacts on endemic fish species, and management problems (see Pollard et al. 1980;Tilzey 1980; McKay 1978; Arthington et al. 1983; McKay 1984; Arthington 1986; Arthington andMitchell 1986; Fletcher 1986; Lloyd et al. 1986; Arthington and Lloyd, in press). Full details of introductions and translocations of speciesin Australia are summarized by McKay (this volume) and the distributions of four species areshown in Figs. 1 and 2. The objectives of this review are to draw attention tothe ecological consequences of species introductions, both planned and unintentional. Most of the paperdeals with introduced species but an account of the translocation of fourendemic Australian fishes into Lake Eacham, Queensland is also included (Fig. 1), because thesetranslocations appear to have caused the

7 8

extinction of the endemic rainbow fish uniqueto this lake, chiefly as a result of predation (see Barlow et al. 1987). This striking example ofthe ecological consequences of ndemic fish translocations was first described by McKay (1987). Throughout the review, conspicuousgaps in knowledge of introduced species. in Australia and research priorities are highlighted, concluding withan overview of current ecological theories that may assist in predicting theconsequences of species introductions, and thus provide the basis for developing protocolson fish introductions and translocations in Australia and elsewhere.

Impacts of Introduced Fishes

The impact of introduced fishesmay involve hybridization with endemic fish species, habitat and water quality alterations, competitionfor space and food, predation and the introduction of exotic parasites and diseases (Courtenayand Stauffer 1984; Moyle et al. 1986). Evidence of these impacts is considered in relationto representatives of the five families introduced into Australia, i.e., Salmonidae, Percidae,Cyprinidae, Poeciliidae and Cichlidae (Table 1).

Hybridization

Hybridization cannot occur in Australia because thereare no indigenous representatives of the introduced species. However, hybridization hasoccurred between introduced Europeancarp, Cyprinus carpio and goldfish, Carassiusauratus (Hume et al. 1983) and between salmon, Salmo salar and brown trout, S. trutta in hatchery conditions(Johnson in Fletcher 1986). Of greater significance in Australia has been hybridizationbetween two varieties of Euroçeancarp to produce the vigorous Boolara strain, which spreadexplosively in the mid-1960's and 1970's and became far more widespread and problematic thanany of the original stocks (Shearer and Mulley 1978; Pollard et al. 1980; Fig. 2). The Boolarastrain is thought to bea hybrid between introduced mirror and fully scaledcarp varieties of unknown origin. This parallels severalcases of intraspecific hybridization among introduced plants,giving rise to locally adaptedas well as aggressive variants (Barrett 1982). Electrophoretic analysis shows that populations ofMozambique tilapia, Oreochromis mossambicus, in Brisbane and Townsville, Queensland (Fig.1) are very similar genetically but both differ significantly from populations of this speciesoccurring in Cairns. The Cairns fish appear to be hybrids between 0. mossambicus and 0. hornorum, and possibly otherspecies of tilapia as well (Mather 1988). Nothing isyet known about the physiological and ecological characteristics and consequent potential for spread of this mixedstrain. G. affinis in Australia are all of the subspecies G.a. hoibrooki (Girard) (Lloyd a:id Tomasov 1985). Thus, there is no threat of hybridization between thisand the nominate subspecies, G.a. affinis, with the attendant implications for future spread andecological impact of hijbrid strains (see Reznik 1981). However, Australian populations ofG. a.hoibrooki shDw marked morphological and genetic differences (Tomasov 1981):Trendall (1982) recorded substantial variations in life-history traits in four populations of G. affinisfrom Western Australia. Hybridization among phenotypically and genetically distinct strains ofthis subspecies is possible and could have unexpected outcomes. 9

Table 1. Introduced freshwater fish that have establishedself-maintaining populations in Australian inland waters. S. sport fish; A, aquarium fish; B,biological control agent. Compiled from various sources (see Arthington 1986). Common Name Purpose of Family/Species Introduction

Salmonidae S Salmo trutta L. Brown trout S Salmo gairdneri Rainbow trout Richardson Sal velinus S fonrinalis (Mitchell) Brook trout S Oncorhynchus tshawytscha Chinook salmon Walbaum S Salmo salar L. Atlantic salmon Percidae Percafluviatilis L. European perch or S redfin Cyprinidae Cyprinus carpio L, European carp S Carassitss aural us L. Goldfish A Tinca tinca (L.) tench S Rutilus rutilus L. roach S Poeciliidae Gambusia affinis Mosquitofish AIB hoibrooki (Girard) Xiphophorus helleri Swordtail A (Gunther) A Xiphophorus maculatus Platy (Heckel) Poecilia reticulata Guppy A/B Peters Poecilia lalipinna Sailfin molly A Le Sueur Phalloceros caudima- One-spot live- A culatus Hensel bearer Cichlidae Ore ochromis mossam- Mozambique mouth- A bicus (Peters) brooder Tilapia mariae Black mangrove or A Bouienger niger cichlid Cichiasoma Convict cichlid A nigrofasciatum GUnther

These examples highlight the need for moreresearch on the genetic attributes of founding populations of successful (and unsuccessful)introduced fishes and on the genetic changeswhich may accompanycolonization. The explosive spread of European carpin Australia is an outstanding example of the differential successof one genetic variant, and it is unfortunatethat we have few data onrelationships between genome, physiologyand life histoiy traits in the highly successful Boolara strain of carp andthe two varieties which have remainedconfined to the Prospect Reservoir, Sydney and theMurrumbidgee frrigation Area of Victoria (Fig. 2).

Habitat Alterations

There is very little evidence thatintroduced fishes have seriously altered aquatichabitats in Australia, either by degradation of waterquality or by removal of aquatic vegetation orother disturbance of forms of disturbance. McCrimmon(1968) attributed increased turbidity to the 10

bottom substrates by Europeancarp during feeding. However, Fletcher et al. (198,5) concluded that populations of carp have not caused increasedturbidity levels in the Lower Goulburn River Basin, Victoria. Moyle et al. (1986) highlighted the direct and indirect influencesof carp on shallow lakes in North America. When carp are removed, turbiditydecreases and native invertebrate-feeding fishes that locate their prey by sight increase (Tayloret al. 1984). The impact of carp on turbidity in Australian aquatic ecosystemsseems to be obscured by the naturally high md variable turbidity of many inland waters (Kirk 1977) and the interactionof hydrological factors with soil type and land degradation. Fletcher et al. (1985) also concluded that Potamogetonpectinatus, a shallow rooted, soft leaved species, may be the only aquatic plant reduced bycarp in Australia. Most of the aquatic plants affected by carp in the United States and Franceare species of Potamogeto'z and Chara (Crivelli 1983). Xiphophorus helleri, the swordtail, is predominantlyherbivorous, taking only a few aquatic invertebrates, but there is no clear evidence that its feedinghas contributed to changes in aquatic macrophyte or algal communities inareas of introduction. Rather, the loss of endemic aquatic macrophytes from Brisbane's urban creeks has resultedfrom dredging, channel modifications, siltation, dumping of domestic and garden rubbish, bankerosion and the invasion of introduced plants (Arthington et al. 1983). The control ofwater hyacinth (Eichhornia crassipes) and other introduced plants with herbicidesmay also have contributed to the decline of so:ne endemic macrophytes. Numerous studies elsewhere have attemptedto separate the effects of introduced speciesper se from the influence of other disturbances and natural environmental phenomena,with only limited success (Moyle etal.1986). Australian researchers have experienced thesame difficulties, as Arthington et al. (1983) and Fletcheret al. (1985) show in work on poeciliids and carp. Nevertheless, this is an area requiring much more study than it hasso far received.

Impacts of Competition on Endemic Fishes

Resource competition for food, perhaps mediated by interferenceand aggressiDn, seems a likely form of impact of many introduced species,particularly the mosquitofish, G. affinis. Taylor et al. (1984) and Arthington and Mitchell (1986)point out that successfu] introduced fishes typically exhibit generalist feeding habitsand trophic opportunism. There is consequently considerable overlap in the diets of introduced and endemicfishes in many systems. G. affinis and Australian melanotaeniids, atherinids, galaxiidsand a retropinnil have very similar diets (Arthington unpublished; Lloyd 1987).Moreover, the diet of the rainbowfish, Melanotaenja duboulayi (Castelnau) changes where largenumbers of mosquitofish and small numbers of rainbowfish coexist. Also M. duboulayi tendsto select larger prey items in the presence of G. affinis, which actively selects very small prey from the invertebrates in thestream environment. These shifts reduce dietary overlap between thetwo species, and may contribute to an effective partitioning of limited food resources. Environmental disturbances causing loss of aquatic macrophytesrequired for rainbowfish spawning habitat may also have been involved in the decline ofthis species (Arthington et al. 1983; Milton and Arthington 1984). There is other evidence that Australian fishes display niche shiftsin coexistence with S. affinis but Lloyd (1987) recordedan expansion of niche width rather than a riductionas 11 predicted by competition theory (O'Connor et al. 1975). Some native fishes show shifts in distribution and abundance as a corollary of dietary niche shifts in the presence of G. affinis (Lloyd 1987). A mutually exclusive distribution pattern exists between mosquitofish and the pigmy perch, Nannoperca australis GUnther, in the Lower River Murray (Lloyd 1984; Lloyd and Walker 1986). Other species show much lower abundances in the presence of G. affinis and X. helleri than do populations of the same species in habitats without introduced fishes (Arthington et al. 1983; Lloyd 1987). The one-spot live-bearer, Phalloceros caudimaculatus and the guppy, Poecilia reticulata, have diets similar to that of the mosquitofish but are less aggressive species (Griffiths 1972). Their impacts on Australian endemic fishes have not been studied, although where guppies and G. affinis are abundant in Brisbane creeks, endemic fishes are rare (McKay 1978; Arthington et al. 1983). The ecological impact of interference competition as a result of aggression and fin-nipping by G. affinis has not been quantified, although it is thought to be important. Lloyd (1987) showed that mosquitofish would attack native fish twice their size and could inflict caudal fin damage. Schoenherr (1981) interpreted aggressive behavior of G. affinis leading to the suppression of reproduction in the Gila (Sonoran) topminnow, Poeciliopsis occidentalis, as interspecific competition for space. However, Meffe (1985) maintained that while some interference does occur, predation by G. affinis has been more important in the decline of the Gila topminnow. McKay (1978, 1984) suggested that large numbers of mosquitofish and swordtails in creek habitats could adversely affect endemic fishes. The decline of endemic fishes has most often occurred in disturbed and polluted habitats which introduced species such as poeciliids, cyprinids and cichlids are able to exploit (Arthington et al. 1983; Courtenay and Stauffer, 1984; Moyle et al. 1986). Nevertheless, G. affinis has colonized undisturbed waterbodies in Australia (Lloyd 1987) and appears to have caused the decline of an endemic rainbowfish, Rhadinocentris ornatus (Regan), in the near pristine environment of Eighteen-Mile Swamp on North Stradbroke Island, Queensland (Fig. 1.). Like G. affinis, the rainbowfish feeds predominantly on terrestial insects at the water's surface and small aquatic invertebrates (Bayly et al. 1975), and this may be a case of competitive displacement (Arthington 1984). However, predation on eggs and fry of the endemic species may also have been responsible. Exploitation competition with brown trout may be involved in the decline and fragmentation of range of the galaxiid, Galaias olidus Gunther, and the decline of river blackfish, Gadopsis marmoratus Richardson, since their diets are similar (Fletcher 1979; Jackson 1978). The diet of introduced carp overlaps at various body sizes with that of several endemic fishes, such as bony bream Nematolosa erebi Gunther, catfish Tandanus tandanus Mitchell, silver perch, Bidyanus bidyanusMitchell,Australiansmelt,Retropinna semoni Steindachner,carp gudgeon, Hypseleotris klunzingeri Ogilby and flat headed galaxias, Galaxias rostratus Klunzinger (see Fletcher 1986). Whether any of these species has been affected by exploitation competition is not known.

Impacts of Predation on Endemic Fishes G. affinis attacks the eggs and fry of important sports fishes, earning the name of "fish destroyer" (Myers 1965) and it is well known that mosquitofish may be piscivorous. However, Australian dietary studies have not produced any evidence of piscivory (Cadwallader 1979; 12

Arthington 1988; Lloyd 1987); G. affinis attacks and eats fish fry in aquaria (JoFnson 1976; Meffe 1985; Lloyd 1987). It is noteworthy that several small-bodied native fishe; seemingly affected by the mosquitofish in Australia have low fecundity (Milton and Arthington 1983b, 1984, 1985) but others do not. Brown trout, S. trutta, Chinook salmon, Onchorynchus tshawytscha and redfin Perca fluviatilis, feed selectively on small endemic fishes and fish fry and may have affected the numbers of galaxiids, pigmy perch, N. australis, and golden perch, Mac quara ambigua Richardson, in southern rivers (Fletcher 1986).

Impacts of Predation in Invertebrates G. affinis has had destructive effects on invertebrate populations in field situations (Stephanides 1964; Legner and Medved 1974) and in controlled experiments. Taxa such as beetles (Walters and Legner 1980), back swimmers (Huribert and Mulla 1981), rotifers, Crustacea (Huribert et al. 1972) and molluscs (Rees 1979) have been affected. In Brisbane streams, G. affinis feeds on small terrestrial insects and immatu:e stages of aquatic insects in the drift and amongst aquatic plants, actively selecting very small prey (Arthington 1988). Such size selective feeding might affect the structure of invertebrate communities by altering recruitment of various taxa. However, the impacts of G. affinis and other invertebrate-feeding fishes on assemblages of invertebrates have not beer. studied in Australia and require attention. Brown trout feeding may have caused the decline of the Tasmanian mouni amshrimp, Anaspides tasmaniae, and has eliminated or reduced several Plecoptera and Trichoptera in Victorian streams (Fletcher 1979). In experimental ponds, carp have caused the decline of a species of Daphnia (Fletcher 1986).

Introduction of Parasites and Diseases

Many biologists have opposed the traffic of introduced aquarium species into Australia due to concern that diseases and parasites may also be introduced (Hoffman 1970; Me Kay 1984). There is already evidence that disease organisms have entered Australia via the aqu irium trade. Goldfish ulcer disease entered Australia this way (Trust et al. 1980) and has reccntly spread rapidly to wild stocks (Whittington et al., in press). Langdon (1986) and Langdon and Humphrey (1987) described a new viral disease of redfin, P. fluvitailis. Concern over imported lish diseases has led to the establishment of quarantine facilities at major ports handling aquarium stocks (McKay 1984). Fish introductions were responsible for importing fish parasites such as fish louse, Argulus (Williams 1980) and anchorworm, Lernaea cyprinacea (Roberts 1978; Hoffman a:id Schubert 1984). However, although G. affinis is host to 22 species of parasites in North America, there is only one Australian record of parasitism, a species of Lernaea found on mosquitofish from the River Murray (Lloyd 1984, 1987). The incidence of imported parasites in Australian endemic fishes is unknown. Moyle (1985) noted that endemic Californian fishes seem at time; to be more heavily parasitized by exotic parasites such as L. cyprinacea than do introduced fishes. 13

Overview of Impacts of Introduced Fishes

The introduced species of most immediate concern in Australia are probably the aquarium species established in sub-tropical and tropical areas of Queensland, particularly G. affinis, X. helleri, P. reticulata and 0. mossambicus. Cold-water species such as salmonids have been in Australia for approximately 100 years and their impact has been of somewhat lesser concern, mainly because they are prized for sport fishing; yet there is growing evidence of their adverse affects. G. affinis has become a very common species in a wide variety of inland waters in 10 major Australian drainage systems (Fig.1). Large populations occur in environments ranging from almost completely undisturbed, dystrophic swamps and streams to fetid urban drains with a wide variety of water quality problems. This fish may form part of the diet of water birds and endemic piscivores, although in the latter case it is avoided when there is a choice (Lloyd 1987). G. affinis is also considered to be less useful than various insectivorous endemic fishes as an agent in mosquito control (Lloyd 1986). Finally, several lines of evidence suggest that this species is partly responsible for the decline of several endemic fishes, including species which play an important part in keeping mosquito populations under control (Arthington et al. 1983; Lloyd 1984, 1986, Lloyd et al. 1986; McKay 1978, 1984). Thus the collective opinion is that G. affinis is a pest species, or ecological uweed (Lloyd 1984; Lloyd et al. 1986; Arthington and Lloyd, in press). X. helleri is also quite common in Brisbane, Queensland and in coastal streams further north, but its impact appears to be one of occupation of space rather than of herbivory. Nevertheless, its persistence and proliferation since introduction are of concern, particularly since it often occurs with G. affinis and the two species together in large numbers seem to depress endemic fish populations (McKay 1978; Arthington et al. 1983). P. reticulata occurs in many Queensland coastal streams (Fig. 1) and has a diet similar to G. affinis. Where guppies and G. affinis are abundant in Brisbane creeks, endemic fishes are rare (McKay 1978; Arthington et al. 1983). P. latipinna, X. maculatus and P. caudimaculatus are much more patchily distributed in Australia, but in sub-tropical and tropical areas of Australia, these species could spread and have an adverse effect on endemic fishes (McKay 1978; Balla et al. 1985). 0. mossambicus occurs in Brisbane, Townsville, Cairns and Western Australia, and new populations have been found in several other parts of Queensland. Some populations have been eradicated, but the species appears to be spreading, at least locally. For instance, numbers of mature fish were carried over the spillway of North Pine Dam, Brisbane, during a recent period of high rainfall, and have colonized (or recolonized) the lower North Pine River. This species also occurs in a tidal waterway in Cairns. It could possibly spread to new river systems via estuaries and coastal waters, in which it is able to breed (Hora and Pillay 1962). Although this species has been declared a noxious species in Queensland, with heavy penalties for translocation and cultivation (Arthington 1986), 0. mossambicus has turned up in isolated farm dams and ponds where its presence can only be attributed to human intervention. Ecological impacts of cyprinids, salmonids and the European perch in Australia are beginning to become evident but are far from fully understood (Pollard et al. 1980; Tilzey 1980; Fletcher 1986). 14

Apparent Extinction of the Lake Eacham Rainbowfish by Translocated Endemic Fishes

The Lake Eacham rainbowfish, Melanotaenia eachamensis Allen and Cross, ocurs only in Lake Eacham, a large crater lake situated in a tropical rainforest catchment on the Atherton Tableland, northern Queensland (Fig. 1). Before 1984 the rainbowfish was an abundant species in the lake (Allen and Cross 1982; McKay 1987; Midgley, pers. comm.), which was also inhabited by two endemic species widespread in northern Queensland. Over the pa;t decade or so, several people noted the decline of the rainbowfish and the appearance in the SLake of four Australian species not previously recorded there. These species included the mout]i almightly, Glossamia aprion (Richardson), the archer fish, Toxotes chatareus (Hamilton), the bony bream, Nematolosa erebi (Gunther) and the banded grunter, Amniataba percoides (Gunther). The Lake Eacham rainbowfish has not been located during recent surveys (Barlow etal.1987). Circumstantial evidence has been presented (Barlow et al. 1987) that its extinction may have been due largely to predation by the carnivorous G. aprion and possibly also the arher fish, T. chatareus; another endemic fish species and a crayfish also appeared to have become extinct in the lake as a result of predation. This first instance of an Australian native fish being exterminated by translocaled endemic fishes was initially noted and recorded by McKay (1987). McKay (pers. comm.) has suggested that this situation is unique in Australia, and could become a case history for rehabilitation of an aquatic ecosystem by the complete elimination of the translocated species in Lake Eacham, and then re-establishment of the rainbowfish by releasing hatchery bred stocks. He further suggests that the introduction of voracious predatory fish into Lake Eacham could achieve the desired eradication of resident, translocated fish species. By far the best candidate for this is the indigenous silver barramundi, Lines calcarifer Bloch. The barramundi is unable to breed in closed lakes and could therefore, in theory, be completely eliminated after extirpation of all translocated fishes either by allowing the introduced stocks to die out, or by a conccrted fishing effort.

The Future

Successful introduced fishes may experience local genetic differentiation follow:ng invasion of new environments (Arthington and Mitcheal 1986). Whether this occurs will depend on the kinds of environments encountered, the range and distribution of genetic variation available to populations, and the inheritance patterns of traits conferring increased fitness (Barret and Richardson 1986). There are several examples of adaptive changes in fish following colonization events. The mosquitofish exists as "warm-adapted' and "cold-adapted" strains in the USA (Otto, 1973) and a western Australian population of S. gairdneri exists with higher temperature tolera nce than its eastern counterparts (Morrissy 1973). The rainbow trout in New Zealand has superior swimming speed compared to ancestral stocks (Tsuyuki and Williscroft 1977). Tomasov (1981) showed that there are both morphological and electrophoretic differences between many Australian populations of G. affinis, but it is not known whether they have resulted from founder effects, genetic drift or local selection. Shifts in thermal tolerance might be expected in G. affinis from southern and ncrthern areas of Australia, where temperature regimes are very different. Likewise, X. helderi and 0. 15 mossambicus may be undergoing selection for cold tolerance in Brisbanesince low winter temperatures have intermittently reduced some populationsin streams and dams (McKay 1978, 1984). Shifts in critical physiological tolerances such as in temperature mean that the future range of an introduced species cannot be predicted with certainty. Appreciation ofthis and other problems has led Australian fisheries authorities to restrict the introductionof aquarium species and to reject the idea of introducing the nile perch, Lates niloticus tostock northern waterbodies for recreational fishing (Barlow and Lisle 1987). In part, the case made against theintroduction of Nile perch was that it could colonize the upper reaches of theMurray-Darling River system and affect endemic fishes which are recruited from these waters. Adult0. mossambicus die at temperatures ranging from 5-140C (Mar et al. 1966; Kirk1972) so this species too could survive the minimum winter temperatures recorded in the upper Murray-Darling River (seeBarlow and Lisle 1987).

An Ecological Approach to Predicting the Effects of Introductions

There is worldwide evidence that successful fish introductions alter the structure andspecies composition of the invaded community. Australian examples are accumulating with increased research on introduced and translocated species. Herbold and Moyle (1986) and Moyle et al. (1986) have argued that introduced species do not fill "vacant niches" as Simberloff (1981) concluded from his review of species introductions. Rather, they fit into the new environment by further compressing the "realized niche" of one or more of the species already present,often to the point where the environment can no longer support the endemic species(Moyle et al. 1986). Li and Moyle (1981) applied the systems analysis technique of "loop analysis" to predict aquatic ecosystem behavior after a species introduction. They suggest thatnutrient-poor or oligotrophic systems are most sensitive and become unstable after introduced species are established. Drawing upon the experience of entomologists in the biological control of pest species, Li and Moyle (1981) suggest four criteria for fish species that arecandidates for introduction: trophic co-adaptation with members of the assemblage receiving the introduced species; narrow niche breadth including stenophagy; low vagility; and freedom from contagious disease and parasites exotic to the new environment. These criteria are the antithesis of the typical characteristics of successful and troublesome introduced species around the world, i.e., zero or little trophic co-adaptation, broadniches, especially habitat and trophic niche, high vagility and infection with parasites and diseases (Arthington and Mitchell 1986). Moyle et al. (1986) suggest that three areas of ecological theory are particularlyrelevant to predicting the effects of introduced species. The theory of island biogeography may answerthe question "how many species can an aquatic ecosystem support?"; the conceptof "limiting similarity" may aid in predicting how morphologically similar species cancoexist in a community; and the analysis of food webs may be useful forunderstanding the trophic interactions of introduced and endemic species. Although each theoreticalapproach has weaknesses, Moyle et al. (1986) conclude that they all point to the creationof inherently unstable fish communities through poorly considered introductions andtranslocations. Fisheries scientists and managers now have access to a substantialbody of theoretical and empirical evidence that "tinkering with fish faunas" (Welcomme 1984)is seldom entirely 16

successful and more often than not has unanticipated and undesirableconsequences. If it is to continue, it must be preceded in every instance by full considerationof the probable consequences for the receiving ecosystem and its endemic fish fauna. This applies equallyto the translocation of fishes between drainage systems, and is particularly importantin Australia of the present time because of the renewed interest in stocking northern inlandwaters with endemic fish species to create recreational fisheries.

Acknowledgements

I wish to acknowledge research grants from the Australian National Parksmd Wildlife Service, Griffith University and the Australian Water Research AdvisoryCouncil For the study of introduced fishes in Queensland. Mr. R.J. McKay, Mr. D.A. Milton,Ms. M. English, Mr. D. Bluhdorn and other colleagues are thanked for theirpart in these studies. I am also indebted to Mr. L.N. Lloyd for his substantial contribution to sections of thispaper on poecihid :ishes.

References

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Reznick, D. 1981. 'Grandfather Effects': The genetics of mterpopulation differences in offspringsize in the mosquitofish. Evolution 35: 941-953. Roberts, R.J. 1978. Fish Pathology. Ballier Tindall, London. Schoenherr, A,A. 1981. The role of competition in the displacement of native fishes by introducedspecies, p. 173-203. In R.. Naiman and D.L. Stolz (eds.) Fishes in North American Deserts. Wiley Jnterscience, New York. Shearer, K.D. and J.C. Mulley. 1978. The introduction and distribution of the carp, Cyprinijs carpio Linnaeus, inAustralia. Australian Journal of Marine and Freshwater Research 29: 551-64. Simberloff, D.S. 1981. Community effects of introduced species. In M.H. Nitecki (ed.) Biotic Crises inEcological and Evolutionary Time, pp. 55-81. Academic Press, New York. Stephanides, T. 1964. The influence of the anti-mosquitofish, Gambusia affinLs,on the natural fauna of Corfulakelet. Praktika Hell. Hydrobiologie Institute 9: 3-5. Taylor, J.N., W.R. Courtenay and J.A. McCann. 1984. Known impacts of exotic fishes in the continentalUnited States, p. 132-173. In W.R. Courtenay and J.R. Stauffer (eds.) Distribution, Biology and Management of Exotic Fishes, JohnsHopkim University Press, Baltimore. Tilzey, R.D.J. 1980. Introduced fish, p. 271-279. In W.D. Williams (ed.) An Ecological Basis forWater Resource Management. Australian National University Press. Canberra. Tomasov. J.F. 1981. Studies on an introduced Species. The mosquitofish- Gambusia affinis. B. Sc, Honours Thesis. Dept of Genetics and Human Variation, La Trobe University, Victoria, Australia. Trendall, J.T. 1982. Covariation in life history traits in the mosquitofish, Gambusia affinis. AmericanNaturalist 119: 774-783. Trendall, J.T. andM,S. Johnson. 1981. Identification by anatomy and gel electrophoresis of Phalloceroscaudirnaculatus (Poe ciiidae) previously mistaken for Gambusia affinis ho! brooki (Poeciliidae). Australian Journal of Marine and FreshwaterResearch 32: 993-996. Trust, T.J., A.G. Khouri, R.A. Austin and L.D. Ashbumer. 1980. First isolation in Australia ofatypical Aeromonas s,zlmonicida. FEMS Microbiology Letters 9: 39-42. Tsuyuki, H. and S.N. Williscroft. 1977. Swimming stamina differences between genotypically distinctforms of rainbow (Salmo gairdneri) and steelhead trout. Journal of Fisheries Research Board, Canada 34: 996-1003. Walters, L.L. and E.F. Legner. 1980. Impact of the desert pupfish, Cyprinodon macularius andGambusia affinis on fauna in pond ecosystems. Hilgardia48: 1-18: Welcomme, R.L. 1984. International transfers of inland fish species,p. 22-40. In W.R. Courtenay and J. R. Stauffer (eds.) Distribution, Biology and Management of Exotic Fishes. Johns Hopkins University Press, Baltimore. Whiuington, RJ., N. Gudkovs, Mi. Carrigan, L.D. Ashburner and SJ. Thurstan (inpress). Clinical, microbiological atid epidemiological findings in recent outbreaks of gold fish ulcer disease due to atypical Aerorrzonas salmonicida insouth-eastern A ustralia. Journal of Fish Diseases. Williams, W.D. 1980. Australian Freshwater Life. Macmillan, Sydney. 116° 1220 DARWIN128°J940 34° GOVE 40° - I 2° 8B 460 1520 8° 1940 / PENINSULA I 2°- CAIRNSLake Eachami 1929 TOWNSVILLE 24° CARNARVO ROCKHAMPTON GERALDTON PERTH1934 GLADSTONE 'p ISBANE 24- ADELAIDE 11925 30Q. - 16°S (I Kilontre 1881 11926SYDNEY 36g, MELBOURNE 0 I 16°E 22° 128° I 34°I 140° I 146'W I 52°I

theCairnsFig. distribution 1. 1929).Australia the of showingpresent Poecilia distribution majorrelic ulala drainage ofin G.coastal divisionsaffinis Queensland in (1-12,each division see below), the (cross-hatched area), localities supporting Oreochromss mossamb,cus(speckled areas), the location of Lake Eacham on the Atheston Tableland, localities and dates of major introductions of Gambusia affirns in (Brisbane, Townsville and recognized by thesouth of Cairns,Australia (e.g., 42L press).Cairns,LakeSouth-westAustralia 1.Queensland; Eyre North-east Water Division; Coastal Resources CoastGascoyne Division; 11. Division;Bulloo-Bancannia Council. River 7. Indian 2.and South-eastShaded Lyons Ocean Division; areas River Division; Coast indicate east 12. Diviaion; of8.Western theTimorCarnarvon, presence 3. PlateauSea DivisionDivision. A - Cape Levesque Coast,Tasmanian B - Finnis Division; River, 9. 4. Gulf Murray-Darlingof moaqustofish Division;withinWestern at least5. Australia). South parts of Numbersthe drainage 1-12 division refer to the drainage divisions Austrahanof Carpentaria Gulf Division; Division;(Aiihington 6. 10. and Uoyd, m 20

1400 !4'o° 152° -24° QUEENSLAND 'I 24°.. I' / I I 4' / I 4 - ¼ I- - .300 Cl) I I I 30 NEW of SOUTH 0i, WALES // R / ,ir1 A '1 36° S I 36L VICTORIA

0 KilometresILLI500 140E° 146° l52 I I I

Fig. 2. South-eastern Australia showing state boundaries and the distribution of three strams of Europeancarp, Cyprintts caIpio. A - Prospect Reservoir strain, B - Mumimbidgee Irrigation Area (Riverina) strain and C- initial distribution of the Boolara strain, first introduced in 1960. Dashed lines indicate the distribution of the Boolara strain in 1977 (redrawn from Pollard etal. 1980). Exotic and Translocated Freshwater Fishes in Australia

RJ. McKAY Queensland Museum P0 Box 300, South Brisbane 4101 Australia

McKay, Ri. 1989. Exotic and translocated freshwater fishes in Australia, p. 2 1-34. In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Publ. 3, 154 p. Asian Fisheries Society, Manila, Philippines.

Approximately 21 species of exotic freshwater fishes have become established in Australian waters, and some 21 indigenous species have been translocated. Two additional exotic species are maintained by regular stocking from Government hatcheries, and a number of unsuccessful introductions and unconfirmed reports of ornamental fish releases are documented in this paper.

The freshwater fish fauna of Australia has been described as depauperate, of recent origin (with a few exceptions), and although similar, has had a dramatic impact on the natural environment to the extent that Weatherley and Lake (1967) and Lake (1971) contended that man-made changes to the environment have been the principal factors in causing a decline in the Australian fish fauna. The construction of large reservoirs, dams and weirs has impounded extensive bodies of permanent, or semipermanent freshwater, and these newly created habitats, albeit of short term evolutionary significance, have attracted the attention of "stocking associations". With mounting political pressure to provide recreational fishing in large reservoirs, without the provision of adequate research funds, and mindful of the reaction of a small but vocal conservation lobby, fishery managers frequently opt for the iranslocation of hatchery-bred native sport or food fish rather than to introduce an exotic species. The first recorded extinction of an indigenous freshwater fish in Australian waters, the Lake Eacham rainbowfish Melanotaenia eachamensis, was almost certainly due to the establishment of the translocated freshwater mouthbrooding apogonid Glossamia aprion (McKay 1987; Caughey 1987; Barlow et al. 1987). The advent of hormone-induced spawning of golden perch Macquaria ambiqua (Rowland 1983a), Murray cod Maccullochella peeli (Rowland 1983b), silver perch Bidyanus bidyanus (Rowland et aL, 1983), barramundi Lates calcarifer (= L. cavzfrons), saratoga Scieropages leichardti (Merrick and Green, 1982), and a number of northern grunters (family Teraponidae), has stimulated the development ofhatchery-bred indigenous freshwater fishes. A register of introduced exotics (Table 1) and translocated indigenous freshwater fishes (Table 2) was compiled by the author from the literature, fisheries reports, and personal communication, and this register, although necessarily incomplete, provides the basis for this account. All introductions and translocations in the register include locality, state to, origin, date, purpose, remarks and drainage system number (Surface Water Resources, 1967, Department National Development, Canberra) and are stored on an IBM compatible computer.

21 22

Definitions

The terminologyassociated with introduced fishes is frequently imprecise (see Courtenay and Stauffer 1984); Ihave largely adopted the definitions given by Bruton and Mcrron (1985), with additional termsdefined:

Exotic any species from another zoogeographic region. This term is usually applied to species from another countryor continent (synonymous terms are alien and foreign).

Indigenous species native to a zoogeographic region, but no: necessarily restricted to a particular lake or drainage systems (synonymous terms are native or local).

Endemic a species that is restricted in its distribution to a particular lake or drainage systems.

Introduction the act of releasing or liberating one or more individuals ofan exotic or indigenous species. The term includes both accidental and deliberate releases.

Stocked an official or approved release for a specific purpose. Frequently employed by fisheries agencies when introducing hatchery-bred exotic or indigenous food or game fishes.

Translocation the movement by man of a species withina zoogeographic region. A term generally used to describe the transplantation of indigenous populations either intentionally or unintentionally by man into a catchment or part of a catchment (above waterfalls) in which it was not naturally distributed, butmay also refer to the movement by man of an exotic species within a zcogeographic region to which it was previously introduced.

Established an introduced exotic or indigenous species that is reproductively successful (synonymous terms are acclimatizedor feral species).

Invasive Species a species which has the ability to become established in natural or semi-natural environments or communities, and to causean ecological imbalance there (synonymous terms are colonizingor weed species).

The introduction and establishment of exotic freshwater fishes in Australia hasbeen regularly documented (Whitley 1951a, 1951b; Roughley 1955; Weatherley and Lake 1967; Lake 1971, 1978; McKay 1977, 1978, 1984, 1986a, 1986b; Pollard et al.1980; Tilzey 1980; Welcomme 1981; Merrick and Schmida 1984; Arthington and Mitchell 1986). Morerecent introductions are given below in the species accounts. 23

Table 1. Exotic fishes established in Australian freshwaters. The states which such species is established is also indicated.

Rainbow trout Salmo gairdneri, WA., S.A., Vic., N.S.W.

Brown trout Salmo lrulla, W.A., S.A., Vic., Tas., NS.W.

Brook trout Salvelinusfontinalis, Tas., N.S.W.

Carp Cyprinus carpio, S.A., Vic., N.S.W., Qd.

Goldfish Carassi,ss aural us all states except N.T.

Tench Tinca linca, S.A., Vic. N.S.W., Tas.

Roach Rutilus rutilus, Vic.

Mosquitofish Gambusia affinis ho! brooki, all states except Tas.

One-spot livebearer Phalloceros caudimaculatus, W.A.

Guppy Poecilia reticulata, N.S.W.,Qd., N.T.

Sailfin molly Poecilia lalipinna, Qd.

Platy Xiphophorus maculalus, Qd., N.T.

Swordtail Xiphophorus helleri, W.A., Qd., N.T.

European perch Percafluvialills, W.A., S.A. Vic., N.S.W., Tas.

Mosambique tilapia Oreochromis mossa,nbicus, W.A., Qd.

Tilapia Oreochromis sp. Qd.

Niger cichlid Tilapia ,nariae, Vic., Qd.

Convict cichlid Cichiasoma (Archocentrus) niqrofascialum, Vic.

Jack Dempsey Cichiasorna (Herichthys) octofasciatwn, Vic.

Weather bach Masqurnus angillicaudatus, A.C.T., Vic.

The translocation of indigenous freshwater fishes has been recently documented (Anon 1980, 1982; Cadwallader 1981, 1983; Cadwallader and Backhouse 1983; Rowland et al. 1983; Cadwallader and Gooley 1984; Merrick and Schmids 1984; Brumley 1987). More recent translocations are discussed in the species accounts. 24

Table 2. Translocations of indigenous freshwater fishes.

Queensland lungfish Neoceralodusforsteri, Qd.

Bony bream Nematalosa erebi, Qd.

Saratoga Scieropages leichardti, Qd.

Gulf saratoga Sc!eropagesjardini, Qd.

Dewfish Tandantis tandanus, Qd.

Long torn Strongylura kreffli, Qd.

Western rainbowfish Melanotaenia splendida, Qd.

Barramundi Lates ca1carfer (= L cavifrons), Qd.

Murray cod Maccullochella peeli, A.C.T., Vic., N.S.W., Qd.

Trout cod Maccullochella ,nacquariensis, N.S.W., Vic.

Australian bass Mac quaria novemaculeata, Vic., Qd.

Golden perch Macquaria ainbigua, A.C.T., Vic., N.S.W., Qd., N.T.

Macquarie perch Macquaria australasica, Vic., N.S.W.

Spangled perch Leiopotherapon unicolor, Qd.

Sooty grunter Hephaestus bidyanus, Vic., N.S.W., Qd., N.T.

Mouth almighty Glossamia aprion, Qd.

Archerfish Toxotes chatareus, Qd.

River blackfish Gadopsis marmoralus, Tas.

Firetail gudgeon Hypseleotris gallii, Qd.

Western carp gudgeon Hypseleotris kluzingeri, Vic.

Sleepy cod Oxyeleotrts lineolatus, Qd.

Table 3. Non-established, or introduced fishes of doubtful status.

Quinnat salmon Oncorhynchus tshawytscha, Vic.

Atlantic salmon Salmo salar, Vic., N.S.W., Tag.

Tiger barb Capoeta let razona, Qd.

Pearl cichlid Geophagus brasiliensis, Qd.

Jewel cichlid Hemichromis bimaculatus, Qd.

Oscar Astronotus ocellatus, Qd.

Cichlid Cichlasoma sp. (hybrid), Qd. 25

Indigenous Species

CERATODIDAE - LUNGFISH Neoceratodusforsteri Translocated to Brisbane, North Pine, Albert, Logan, Coomera, and Caboolture Rivers, but established only in the Brisbane and Pine River systems with any success (O'Connor 1897b; Merrick and Schmida 1984).

CLUPEIDAE - HERRINGS Nematalosa erebi Established translocations in Lake Morris, Tinaroo Dam, and Lake Eacham, northern Queensland (Anon 1982).

STEOGLOSSIDAE - BONYTONGUES Scieropages leichardti Translocated during the 1960's to Callide Dam, Borumba Dam, Moogerah Dam, Hinze Dam, Mary River, from (Borumba Dam) and North Pine Dam (pond escape)southern Queensland. Hatchery-bred fish sold in Queensland (Merrick and Green 1982).

Scieropages jardini

Tinaroo Dam northern Queensland (Anon 1982).

PLOTOSIDAE - EEL-TAIL CATFISH Tandanus tandanus Translocated to Beatrice River, Lake Morris and Tinaroo Dam from Enoggera Dam, southern Queensland; to the Wimmera River, Victoria from the Murray River. Now produced by hatcheries and sold for stocking purposes (Anon 1982).

BELONIDAE - NEEDLEFISH Strongylura kreffti

Stocked into Callide dam (S.H. Midgley, pers. comm). 26

MELANOTAENIIDAE Melanotaenia splendida

Translocated to Bolgu Island, Tones Straits, for mosquito control.

CENTROPOMIDAE- BARRAMUNDI Lates calcarfer

Translocated to Tinaroo Dam where they cannot establish. Hatchery-bred fishare sold in Queensland (Shacklee and Salini 1983).

PERCICHTHYIDAE- BASSES AND CODS Maccullochella peeli

Translocated to many localities within natural range and to Lake Charlegrark, Wimmera River lakes, Victoria. An early unsuccessful introductionto the Yarra River, Viccoria (Wilson 1857). Translocated from Condamine River to Obi Obi Creek, Mary River,Queensland in the 1880's (Cadwallader 1978,1983; Cadwallader and Backhouse 1983; Rowland 1983b; Cadwallader and Gooley 1984). Hatchery-bred fish sold in Victoria, New SouthWales and Queensland.

Maccullochella macquariensis

Stocked in Lake Sambell, Victoria, Seven Creeks and Glenbawn Dam, New South Wales (Cadwallader 1983; Cadwallader and Gooley 1984).

Mac quaria novemaculeata

Introduced to Lake Manchester and Poona Dam Queensland.

Mac quaria ambigua

Stocked in many reservoirs in New South Wales and Victoria (Cadwallader 1978, 1983; Anon 1980; Rowland et al.1983; Rowland 1983a; Brumley 1987). Limited stocking in Queensland to date (Stephenson and Grant 1957). Stocked in Lake Burley Griffn,Canberra, (Pratt 1979; Robinson 1982). Hatchery-bred fish now available. 27

Mac quaria australasica Stocked in reservoirs in New South Wales andVictoria (Cadwallader and Rogan 1977, Cadwallader 1981b, 1983). A possible introduction toLake Manchester, Southern Queensland with M. novemaculeata from the NepeanRiver (S.H. Midgley, pers. comm)

Bidyanus bidyanus

Stocked in reservoirs in New South Wales (Anon1980; Rowland et al. 1983), and Wimmera River, Victoria (Cadwallader 1983), alsostocked in Queensland dams (Yolk Creek, Enoggera, Kinchant, Tinaroo, Borumba, Boondooma andAwoonga) and Mary River.

Hephaestus fuliginosus

Stocked in 23 sites in Queensland from TinarooDam southwards to Gin Gin (Anon 1980, 1982a). Early reports suggest that this species has becomeestabished in some coastal rivers.

Liopotherapon unicolor Stocked in Maroochy River in the 1960s (S.H.Midgley pers. comm.) and into the North Pine Dam after 1973 where it has becomeestablished. Introduced to the Brisbane River system.

APOGONIDAE - CARDINAL FISHES Glossamia aprion Stocked in some northern dams by private stockingagencies (Grant, 1982). Introduced to Lake Eacharn (see Arthingtonton - this volume).

Toxotes chatareus Stocked in Tinaroo Dam, Copperload Darnand Lake Eacham, Queensland (Anon 1982a; Barlow et al. 1987).

GADOPSIDAE - BLACKFISH Gadopsidae marmoratus

Translocated to Huon and Derwent Rivers, Tasmania(Merrick and Schmida 1984). 28

ELEOTRIDAE- GUDGEONS Hypseleotris galii

Introduced to Boigu Island, Torres Straits for mosquito control.

Hypseleotris klunzingeri

Introduced to Wimmera River lakes, Victoria with stocked species (Cadwalladerand Backhouse 1983).

Exotic Species

SALMONIDAE -SALMON AND TROUT Oncorhynchus tshawytscha

Maintained by stocking in south-western Victorian lakes (Cadwalladerand Eden 1981; Cadwallader and Backhouse 1983).

Salmo gairdneri

The most important salmonid stocked in Australia. Widespreadin Victoria, New South Wales and Tasmania (Roughley 1955; Lake, 1957; Weatherley andLake 1967; Nicholls 1957, 1958a, 1958b, 1958c, 1958d; Wharton 1969; Lynch 1970; Tilzey1971, 1972, 1976, 1977, 1980; McDowall and Tilzey 1980; Cadwallader and Tilzey 1980;Welcomme, 1981; Jackson 1981; Jackson and Davies 1983; Barnham 1983; Cadwallader 1983; Cadwalladerand Backhouse 1983; Brown, 1984; Baxter 1985; Baxter et al. 1985).

Salmo trutta (see also S. gairdneri)

Widespread in Victoria, New South Wales, Tasmania and south-westernWestern Australia (Roughley 1955; Tilzey 1971; Jackson and Williams 1980; Merrick and Schmida194).

Salmo salar

Maintained by stocking in impoundments in New South Wales andTasmania (Francois 1965; Hortle 1986). 29

Salvelinusfontinalis Stocked in impoundments in New South Wales and Tasmania (Lake 1971; McDowall and Tilzey 1980; Cadwallader 1983; Merrick and Schmida 1984).

CYPRINIDAE - CARP AND GOLDFISH Cyprinus carpio First introduced to Australia in 1872 and now widespread through the Murray-Darling system (Stead 1929; Lake 1959, 1967a, 1967b; Butcher1962; Wharton 1971, 1979; Shearer and Mulley 1979; Smith and Pribble 1979; Geddes 1979; Mulley and Shearer 1980;Hume et al. 1983a, 1983b; Cadwallader and Backhouse 1983; McKay 1986c, 1987a; Arthington and Mitchell 1986).

Carassius auratus Widespread in New South Wales, Victoria and western Queensland(Mitchell 1976; McDowall and Shearer 1980).

Capoeta tetrazona

Introduced to Enoggera Creek, Brisbane, 1987.

Rutilus rutilus Common in some southern Victorian streams (Lake 1979; McDowall andShearer 1980; Cadwallader and Backhouse 1983; Merrick and Schmida 1984).

Tinca tinca Introduced to Tasmania and Victoria (Weatherley 1962;Weatherley and Lake 1967; Cadwallader and Backhouse 1983; Merrick and Schmida 1984).

COBITIDAE - LOACH Misgurnus anguillicaudatus Released by aquarists to Lake Burley Griffin, Yarra River and OvensRiver (Allen 1984, 1986c, 1987a). 30

POECILIIDAE - LIVEBEARERS Gambusia affinis hoibrooki

Widespread throughout mainland Australia (Whitley 1951a, 1961b; Mees 1977; Pollard et al. 1981; Milton and Arthington 1983; Merrick and Schmida 1984; Lloyd 1984; Lloyd and Tomasov 1985; Arthington, this volume and references therein).

Poecilia reticulata

Common in urban streams throughout coastal Queensland (McKay 1977, 1978, 1984, 1986c; Arthington et al. 1983).

Poecilia latipinna

Established in Hervey Bay and Sandgate Lagoon, Brisbane (Mckay 1978, 1986c).

Phalloceros caudimaculatus

Established near Perth, Western Australia (Trendall and Johnson 1981).

Xiphophorus helleri

Common in urban creeks Brisbane, Ipswich and Gladstone Queensland (McKay 1977 1978, 1984; Arthington et al. 1981, 1983; Arthington and Mitchell 1986).

Xiphophorus maculatus

A rapidly spreading invasive species established in the Brisbane region, Babind a, Tully and Gordonvale, Queensland (McKay 1978, 1984, 1986c; Milton and Arthington 1983).

PERCIDAE - PERCH Perca fluviatilis

Established in western Victoria, New South Wales, Tasmania, Western Australia, and South Australian Gulf divisions (Weatherley 1963, 1977; Weatherley and Lake 1967; Cad'wallader and Backhouse 1983; Merrick and Schmida 1984; Baxter et al. 1985). 31

CICHLIDAE - CICHLIDS Oreochromis mossambicus

A rapidly spreading invasive species established in Queensland and Western Australia (McKay 1984, 1986c; Allen 1982; Arthington et al.1984; Arthington and Mitchel 1986; Arthington this volume).

Tilapia mariae

Established in thermal waters of a power station in Victoria (Cadwallader et al. 1980) and Cairns area Queensland.

Cichiasoma nigrofasciatum

Established in thermal waters of a power station in Victoria (Cadwallader et al. 1980).

Cichiasoma octofasciatum

Reported to be established (now declining population?) in thermal waters of a power station in Victoria (Cadwallader et al. 1980; N. Halliwell, pers. comm.).

Geophagus brasiliensis Introduced to the Bajool area, Queensland, and in an ornamental pond, Rockhampton (McKay 1986c).

Hemichromis bimaculatus

Escaped from ornamental ponds cairns, Queensland and established in urban drains (McKay 1986c).

Astronotus ocellatus

Introduced to several urban creeks in Queensland but not yet established.

Cichiasoma species

Introduced to Brisbane River but unlikely to establish. 32

References

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Effects of urban development and habitat alterations on the distribution and abundance of native and exotic freshwater fish in the Brisbane region. Queensland. Australian Journal of Ecology 8: 87-101. Arthington, A.H., RJ. McKay, and DJ. Milton. 1984. Occurrence of the introduced cichlid Oreochromis mossambicu.s (Peters) in Queensland. Australian Journal of Marine and Freshwater Research 35: 376-372. Arthington A. H. and D.S. Mitchell. 1986. Aquatic invading species, p. 34-53. In R.H. Groves and JJ. Burdon (eds.) Eco. ogy of Biological Invasions: An Australian Perspective. Barlow, C.G., A.E. Hogan and U. Rogers. 1987. Implications of translocated fishes in the apparent extinctions in the wild ol the Lake Eacham rainbowfish, Melanotaenia eachamensis. Australian Journal of Marine and Freshwater Research 38: 897-902. Bamharn, C. 1983. Listing of Salmonid liberations 1968-1983. Fisheries and Wildlife division, Victoria,p. 77. Bamham, C.A. 1977. 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Past and present distribution of golden perch Macquaria ambigua (Pisces: Percichthidae) in Victoria with reference to release of hatchery produced fiy. Proceedings of the Royal Society of Victoria 99(3): 111-116. Brumley, A.R., A.M. Morison and J.R. Anderson. 1987. Revision of the conservation status of several species of warinwattr native fish after surveys of selected sites in northern Victoria (1982-1984), Arthur Rylah Institute for Environmental Research. Techtiical Report Series 33: 1-93. Bruton, M.N. and S.V. Merron. 1985. Allen and translocated aquatic animals in southern Africa: a general introduction checklist and bibliography. South African National Scientific Programs Report 113: 1-71. Butcher, A.D. 1947. Quinnat salmon in Victorian inland waters. Fisheries and Game Department, Victoria, Fisheries Pamphlet 4: 1-28. Butcher, A.D. 1962. The implications of the introduction of European carp into Victorian Waters. Fisheries and Wildlife Depa-tment, Victoria 4: 1-28. Cadwailader, P.L. 1978. Some causes of the decline in range and abundance of native fish in the Murray-Darling River systs m. Proceedings of the Royal Society of Victoria 90: 211-224. Cadwallader, P.L. 1979. Distribution of native and introduced fish in the Seven Creeks River system, Victoria. Australian Journal of Ecology 4: 361-385. Cadwallader, P.L. l981a. Fish population biology and the role of hatchery produced fish. Proceedings of the Sixteenth Assembly of Australian Freshwater Fishermen, pp. 21-24. Cadwallader, P.L. 198lb. Pest and present distributions and translocations of macquane perch Macquaria ausrralasica (Pisces: Percichthyidae), with a particular reference to Victoria. Proceedings of the Royal Society of Victoria 93: 23-30. Cadwallader, P.L. l983b. A review of the fish stocking in the larger reservoirs of Australia and New Zealand. FAO Fisheries Circular No. 757,p. 1-38. Cadwallader, PU. and G.N: Backhouse. 1983. A guide to the Freshwater Fish of Victoria. Victorian Government Printing Office, Melbourne,p 249. Cadwallader, P.L. and A.K. Eden. 1981. Food and Growth of hatchery-produced chinook salmon, Oncorhychus tshawytscha (Walbaum) in land- locked Lake Purrumbete, Victoria, Australia. Journal of Fish Biology 18: 321-330. Cadwallader, P.L. and G.J. Gooley. 1984. Past and present distributions and translocations of Murray cod Maccullochella peei and trout cod M. macquariensis (Pisces: Percichthyidae) in Victoria. Proceedings of the Royal Society of Victoria 96: 33-43. Cadwallader, PU. and P.L. Rogan. 1977. The macquarie perch, Macquaria australasica (Pisces: Percichthyidae), of Lak;: Eildon, Victoria. Australian Journal of Ecology 2: 409-418. Cadwallader, P.L. and R.DJ. Tilzey. 1980. The role of trout as sport fish in impounded waters of Victoria and New South Wales. Bulletin of the Australian Society for Limnology 7: 17-29. Cadwallader, PU. G.N. Backhouse and R. Fallu. 1980. Occurrence of exotic tropical fish in the cooling pondage of a power sation in temperate south-eastern Australia. Australian Journal of Marine and Research 31: 54 1-546. Courtenay, W.R. Jnr. and JR. Stauffer, Editors. 1984. Distribution, Biology and Management of exotic fishes. John Hopkin:; University Press, Baltimore, p. 430. Fletcher, A.R. and H.J. Pribble. 1979. A review of the effects of carp (Cyprinus carpio U.) on fish and invertebrates. Fishcries and Wildlife Division, Victoria, Carp program Publication 3: 1-17. Francois, D.D. 1965. Atlantic salmon for New South Wales. Australian Natural History 15: 61-64. Geddes, M.C. 1979. Salinity tolerance and Osmotic behaviour of European carp (Cyprinus carpio U.) from the River Murray, Australia. Transactions of Royal Society of South Australia 103: 185-189. 33

Grant, E.M. 1982. Guide to Fishes. Department of Harbours and Marine, Brisbane, p.896. Halliwell, N. 1987. The continuing debate: feral fish populations and translocations oflocations. Aquarium Life Australia 1:27-28. Hortle, M. 1986. Salmon Farming in Tasmania. Australian Fisheries 45: 18-20. Hume, D.J., A.R. Fletcher and A.K. Morison. l983a. Interspecifichybridization between carp (Cyprintss carpio L.) and goldfish (Carassius auratus L.) from Victorian waters. Australian Journal of Marine andFreshwater Research 34: 915-919. Jackson P.D. 1979. Survey of fishes in the West branch of the Tarwin River aboveBerrys Creek. Victorian Naturalist 97: 11-14. Jackson, P.D. 1981. Trout introduced into south-eastern Australia: their interactionwith native fishes. Victorian Naturalist 98: 18-24. Jackson, P.D. and W.D. Davies. 1983. Survey of the fish fauna in theGrampians region, South Western Victoria. Proceedings of the Royal Society of Victoria 95: 39-51. Jackson, P.D. and W.D. Williams. 1980. Effects of brown trout, Salmo trultaL., on the distribution of some native fishes in three areas of southern Victoria. Australian Journal of Marine and Freshwater Research 31:61-67. Lake, J.S. 1957. Trout populations and habitats in New South Wales. AustralianJournal of Marine and Freshwater Research 4: 414-450. Lake, J.S. 1959. The Freshwater Fishes of New South Wales. Chief Secretary'sDepartment, N.S.W. State Fisheries Research Bulletin 5 1-20. Lake, J,S. 1967a. Freshwater fishes of the Murray-Darling River system. Chief Secretary'sDepartment, N.S.W. State Fisheries Research Bulletin 7: 1-48. Lake, J.S. l967b. Principal fishes of the Murray-Darling River system, p 192-213.In A.H. Weatherley (ed) Australian Inland Waters and their Fauna. Australian National University Press, Canberra. Lake, J.S. 1971. Freshwater Fishes and Rivers of Australia. Nelson, Melbourne, pp.61. Lake, J.S. 1978. Australian Freshwater Fishes. Nelson, Melbourne, pp. 160. Uoyd, L. 1984. Exotic Fish: useful additions or animal weeds. Fishes of Sahul1: 31-34, 39-43. Uoyd, L. and J. Tomasov. 1985. The status of the genus Gambusia in Australia. AustralianJournal of Marine and Freshwater Research 36: 1-6. Lynch, D.D. 1970. Species of Salmonidae in Tasmania. Tasmanian Year Book1970: 84-96. McDowall, R.M. and K. Shearer. 1980. Family Cyprinidae. In McDowell, R.M.(ed.) Freshwater fishes of south-eastern Australia. Reed, Sydney. McDowall R.M. and R.DJ. Tilzey. 1980. Family Salmonidae, p. 72-78. In R.M.McDowall (ed.) Freshwater Fishes of South-eastern Australia. Reed, Sydney. McKay, R.J. 1977. The Australian aquarium fish industry and the possibility of theintroduction of exotic fish species and diseases. Department of Primary Industry, Fisheries Division, Fisheries Paper 25: 1-36. McKay R.J. 1978. The exotic freshwater fishes of Queensland. Australian NationalParks and Wildlife Service. Canberra, Report 1-444. McKay RJ. 1984. Introductions of exotic fishes in Australia, p. 117-199. In Courtenay,W.R. Jnr, and Stauffer, J.R. Jnr. (eds.) Distribution, Biology, and Management of Exotic Fishes. John Hopkins University Press, Baltimore. McKay, RJ. l986a. It's your problem too! A Pandora's box. Aquarium Life Australia1(4): 36-40. McKay, R.J. 1986b. It's your problem too! The problem of import restrictions.The intercontinental transfer of ornamental freshwater fishes. Aquarium Life Australia, 2(1): 35-38. McKay, R.J. 1986c. It's your problem too! Part 3. The Australian Introductions. AquariumLife Australia 2(2): 37-39. McKay, RJ. l987a. It's your problem too! Part 4. The Australian Introductions.Aquarium Life Australia 2(3): 39-40. McKay, R.J. 1987b. It's your problem too! Part 5. History of legislation pertaining tothe Australian aquarium industry. Aquarium Life Australia 2(4): 37-39. McKay, R.J. and N. Halliwell. 1987. It's your problem too! Part 6. The ornamentalfish farming industry in Australia. Aquarium Life Australia 2: 28-30. Mees, G.F. 1977. The status of Gambusia in south-eastern Australia. Records of theWestern Australian Museum 6(1): 27-3 1. Merrick, J.R. and L.C. Green. 1982. Pond culture of the spotted barramundi,Scierophages leicharti (Pisces: Osteoglossiidae). Aquaculture 29: 171-176. Merrick, J.R. and G.E. Schmida. 1984. Australian Freshwater Fishes Biology andManagement, Griffin Press, Adelaide, pp. 409. Midgley, SF1. 1982. A biological survey of the streams and impoundmentswithin the Brisbane Forest Park. Brisbane Forest Park Administration Authority, Brisbane. Milton, D.A. and A.H. Arthington. 1983. Reproductive biology of Gambusia affinishoibrooki Baird and Girard, Xiphophorus helleri (Gunther) and X. ,naculatus (Heckel) (Pisces: Poeciiidae) in Queensland, Australia. Journal of FishBiology 23: 23-41. Mitchell, P.A. 1976. Aspects of growth and feeding in golden carp (Carassius auratus)from South Australia. Transactions of the Royal Society of Australia 103: 137-144. Mulley, J.C. and K.D. Shearer. 1980. Identification of the natural "Yanco" +Boolara" hybrids of the carp, Cyprinus carpio. Australian Journal of Marine and Freshwater Research 31: 409-411. Nicholls, A.G. 1957. The Tasmanian trout fishery. 1. Sources of information and treatmentof data. Australian Journal of Marine and Freshwater Research 8: 451-475. Nicholls, A.G. 1958a. The population of a trout stream and the survival of releasedfish. Australian Journal of Marine and Freshwater Research 9: 319-350. Nicholls, A.G. l958b. The Tasmanian trout fishery. 3. The rivers of the north and east.Australian Journal of Marine and Freshwater Research 9: 167-190. Nicholls, A.G. l958c. The Tasmanian trout fishery. 2. The fishery ofthe north West region. Australian Journal of Marine and Freshwater Research 9: 19-59. Nicholls, A.G. l958d. The Tasmanian trout fishery. 4. The rivers of thesouth and south-east. Australian Journal of Marine and Freshwater Research 12: 17-53. Nicholls, R. 1981. Exotic fish in Derebin Creek. Wildlife in Australia 18:26-27. O'Connor, D. 1897a. Fish acclimatization in Queensland. Proceedings of the RoyalSociety of Queensland 12. O'Connor, D. l897b. Report on preservation of Ceratodus. Proceedings of theRoyal Society of Queensland 12. Pollard, D,A., D.C. Uewellyn and R.D,J. Tilzey. 1980. Management of freshwaterfish and fisheries, p. 227-270. In Williams, W.D. (ed,) An Ecological Basis for Water Resource Management. Australian National UniversityPress, Canberra. Pratt, B. 1979. The Canberra Fisherman. Australian National University Press,Canberra, p. 123. 34

Robinson, S.E. 1982. The ecology of Golden perch (Macquaria a,nbigua) in LakeBurley Griffin and Lake Ginnindera. Department of the Capital Territosy, A.C.T., Conservation Service, Conservation Memorandum11: 1-27. Roughley, T.C. 1955. Fish and Fisheries of Australia. Angus and Robertson,Sydney, p. 343. Rowland, S., J. Dirou and P. Selosse. 1983. Production and stocking of goldenand silver perch in N.S.W. Australian Fisheries 42: 24-28. Rowland, S.J. 1983, The hon-none-induced ovulation and spawningof the Australian freshwater fish golden perch. Iv'acquaria ambigua (Richardson) (Percichthyidae). Aquaculture 35: 221-238. Russell, DJ. 1987. Aspects of the limnology of tropical lakes in Queensland- with notes on their suitability for recreational fb,heries. Proceedings of the Royal Society of Queensland 98: 85-91. Shacklee, J.B. and J.P. Salini. 1983. Studies suggest multiple stocks of Australianbarramundi. Australian Fisheries 42: 36-38. Shearer, K.D. and J.C. Mulley. 1978. The introduction and distribution of the carp, Cyprinu.s carpio Linnaeus, in Australia. Australian Journalof Marine and Freshwater Research 29: 551-563. Smith, GJ. and H.J. Pribble 1978. A review of the effects ofcarp (Cyprinus carpio L.) on aquatic vegetation and water'owl. Fisheries and Wildlife Division, Victoria, Carp Program Publication 4: 1-16. Stead, D.G. 1913. An account of some experiments in the acclimatizationof two species of Australian freshwater perch. Report of the Australian Association for the Advancement of Science 14(D): 279-288. Stead, D.G. 1929. Introduction of the great carp, Cyprinus carpio intowaters of New South Wales. Australian Zoologist 6: 10(-l02. Tilzey, R.D.J. 1972. the Lake Eucumbene trout fishery. Fishermen,N.S.W. 4(6): 1-9. Tilzey, R.D.J. 1976. Observations on interactions between indigenous Galaxiidae and introduced Salmonidae in the Lake Eucumbenecatchment, New South Wales. Australian Journal of Marine and Freshwater Research27: 551-564. Tilzey, R.D.J. 1977. Key factors in the establishment andsuccess of trout in Australia. Proceedings of the Ecological Society of Australia 10: 105. 97- Tilzey, R.D.J. 1980. Introduced fish,p. 27 1-279. In W.D. Williams (ed.) An Ecological Basis for Water Resource Management. Australian National University Press, Canberra. Trendall, J.T. 1982. Covariation of life history traits in the mosquitofish,G. affinis. American Naturalist, 119(6): 774-783. Trendall, J.T. and M.S. Johnson. 1981. Identification byanatomy and gel electrophoresis of Phalloceros caudimaculatus (Poec iiidae), previously mistaken for Gambusia affinjs hoibrooki (Poeciiidae). Australian Journal ofMarine and Freshwater Research 32: 9)3-996. Weatherley, A.H. 1962. Notes on distribution, taxonomy and behaviour oftench Tinca tinca (L.) in Tasmania. Annals and Magazine of Natural History 13(4): 713-719. Weatherley, A.H. 1963. Zoogeography of Percafluviatill.r (Linnaeus) and Percaflavescera (Mitchell) with special reference tc the effects ofhigh temperature. Proceedings of the Zoological Society of London 141: 557-576. Weatherley, A.H. 1977. Percafluviazilis in Australia. Zoogeographic expressionof a life-cycle in relation to environment. Jounial of the Fisheries Research Board of Canada 34: 1464-1466. Weatherley, A.H. and J.S. Lake. 1967. Introduced fish species in Australian inland waters, p. 217-239. In A.H. Weatherley (ed.) Australianinland waters and their fauna. Australian National University Press, Canberra. Welcomme, R.L. 1981. Register of international transfers of inlandfish species. FAO Fisheries Technical Paper 213: 1-120. Wharton, J.C.F. 1969. Trout liberations in Victorianstreams and lakes from 1958 to 1967. Fisheries and Wildlife Department, Victoria. Circular 19: 1-357. Fisheries Wharton, J.C.F. 1971. European carp in Victoria. Fur, Feathersand Fins 130: 2-11. Wharton, J.C.F. 1979. Impact of exotic animals, especially Europeancarp Cyprinus carpio, on native fauna. Fisheries and Wildlife Paper, Victoria 20: 1-13. Whitley, G.P. 195la. Introduced Fishes- 1. Australian Museum Magazine 10: 198-200. Whitley, G.P. 1951b. Introduced Fishes -2. Australian Museum Magazine10: 234-238. Whilley, K. 1980. Dams boosting fish stocks. Australian Fisheries39(6): 16-17. Wilson, E. 1857. On the Murray River cod, With particulars ofexperiments instituted for introducing this fish in the River Yarra-Yarra. Proceeding of the Royal Society of Victoria 2: 23-24. The Status of the Exotic Aquatic Organisms in China

TAN YO-JUN TONG HE-Yl Shanghai Fisheries Universiiy 334 Jun GongRoad Shanghai, China

Tan Yo-Jun and Tong He-Yi. 1989. The status of the exotic aquatic organisms in China, p. 35-43. In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, lS4p. Asian Fisheries Society, Manila, Philippines.

A total of 109 species of fish which includes 21 species of food fishes, 88 species of tropical aquarium fishes, 1 amphibian, 2 crustaceans, 6 molluscs and 7 seaweeds have been introduced into mainland China. Most of the food fish species are used for aquaculture. A strict quarantine procedure is adopted when species are introduced, and are released for commercial culture only after a number of years of experimentation and observation. As most introductions are tropical species, which are generally unable to overwinter under natural conditions, none of the introductions are known to have had deleterious effects on the indigenous flora and fauna.

In order to develop China's inland and marine culture fisheries and other purposes, a great number of exotic aquatic species were introduced from different countries and regions of the world. There are about 125 species known to have been introduced into China. Among them are 109 species of fish which includes 21 species of food fishes and 88 species of tropical aquarium fishes,1 amphibian, 2 crustaceans, 6 molluscs and 7 seaweeds. Some of them have been successfully cultured in different parts of the country and have made a considerable contribution to the production. Some are still in the stage of experimental culture.

Exotic Aquatic Organisms in China

Pisces Five species or subspecies of Cyprinidae were introduced into China (Table 1). Carassius auratus cuvieri which was called silver crucian carp in China, indigenous toLake Biwa of Japan, was introduced into the country in 1976 andquickly popularized after 2-3 years trial. The principles of breeding and seed production are similar to that of local crucian carp Carassius auratus auratus. In the commercial production, silver crucian carpis commonly polycultured with the Chinese carps. It is now extensively cultured in China, particularly in ChangjiangRiver Basin. Funtius gonionotus was introduced from Thailand in 1986. It has been experimentally monocultured or polycultured in ponds and rice fields in Guangdong Province. Labeo rohita is indigenous to the Ganges and was introduced from Thailand in 1978. It is beingcultured experimentally in the southern parts of China. Catla catla was introduced from Bangladeshin

35 36

1973. It has been cultured insouthern parts of China, such in an experimental as in Guangdong Provincc, but is still stage. Scattered mirror carp isa strain of Cyprinus carpio which by German fish culturists was selected many years ago. Thirty thousand fertilizedeggs were intrcduced from Japan in 1982 andten thousand fingerlingswere introduced from the Federal Republic Germany in 1984. The exotic of mirror carp has a fast growthrate, higher resistance to cold, is easier to culture and catch, andtherefore it is now extensively China. cultured in the northrnparts of Colossoma bidens of Serrasalmidae, indigenous to South America,was introduced in 1985 via Hong Kong. It is beingexperimentally cultured in southernChina. Three species of Clariidae havebeen introduced into China. Clarias batrachus Clarias macrocephalus and were introduced from Thailand in 1982and 1978, respectively. The latteris also distributed in southernYunnan Province of China.Clarias lazera Africa in 1981. In comparison was introduced from with the local catfish Clariasfuscus, the exotic cat fisheshave more favourable characteristics for intensiveculture, and are extensively China. cultured n southern Pangasius sutchi (Pangasidae) was introduced from Thailand in 1978,and at present is experimentally cultured in GuangdongProvince. Ictalurus punctatus and Ictalurus nebulosus were introduced fromthe United States in 1984 and are experimentally culturedin Hubei Province and Beijing. Three coldwater salmonids have been introduced intoChina. Salmo gairdneriwas first introduced from the DemocraticPeople's Republic of Korea in slowly and remained 1959, but culture developed at experimental stage during 1959-1976.Since then, rainbow has developed and it is trDut culture now extensively cultured throughout 16provinces and autonomous regions. In 1983, The Donaldsonsuper rainbow trout was introduced from Washington, USA. This species the University of has a faster growth andstronger resistance to cold. Chinahas succeeded in rainbow trout cultureand seed production. Food fish are mainlycultured in concrete tanksor raceways with running cok addition cage culture in lakes, water; in reservoirs and coastal waters is alsocarried out. Coregonus peled and Coregonus sp. whichare species from USSR and North America from Japan in 1985. They originally, were introduced were cultured in a reservoir of HeilongjiangProvince for Five species of Cichlidae have experiments. been introduced into China.Oreochromis mossambicuswas introduced into China from Vietnamin 1957, and for a long period. It is was polycultured with Chinesecarp; in ponds not considered a suitable speciesfor culture and is being Oreochromjs nilorjcus, introduced replaced by in 1978. It has beenmonocultured in running warm polycultured in ponds. The hybrid water or of 0. mossambicus X 0.niloticus is important in polyculture with Chinese carps. Oreochromisaureus was introduced in 1981 in order offspring through hybridization. to get over O% male Tilapias are commonly culturedin ponds, runningwarm water, cages, etc. But Sarotherodon galilaeus andTilapia zulu which kept in experimental were introduced in 19 1 are still hatcheries. Tilapias are unableto overwinter in natural waters in of China. most parts Largemouth bass Micropterussalmoides, indigenous to the freshwater North America, lakes and rivers in was introduced into China in 1983 viaHong Kong. Largemoutibass is considered as one of the best foodfish species cultured in China. Gambusia affinis of Poeciliidae,indigenous to North America, several decades ago for controling was introduced into China malaria. It is widespread inShanghai and Jiangsu iirovinces and is also cultured in aquaria. 37

It is well-known that the traditional aquarium fish of China are goldfish and brocaded carp. They were selected or bred from crucian carp and common carp, respectively. Many aquarium fishes were introduced from different countries and regions. The preliminary list of aquarium fish introduced into China is given in Table 2.

Crustacea Red crayfish Procambarus clarkii (Astacidae), indigenous to America, was introduced into China via Japan many years ago. It is self-reproducing in natural waters near Shanghai. The giant freshwater prawn Macrobrachium rosenbergii (Palaemonidae), indigenous to the Indo-Pacific region, was introduced into China from Japan. It is much bigger than the native freshwater shrimp Macrobrachium nipponense. At present, itis being mass cultured in Guangdong, Guangxi, Zhejiang, Fujian, Shanghai and Beijing.

Mollusca

The Pacific oyster, Crassostrea gigas (Ostreidae), was introduced into China from Japan in 1979-1980. At present, it is being experimentally cultured in bays of Zhejiang Province. It is a good species with big size, fast growth and strong adaptability. The bay scallop Argopecten irradians (Pectinidae), indigenous to the Atlantic coast of the United States, was introduced into China in 1982. It is now cultured economically in some coastal areas of Shandong Province. Red abalone Haliotis rufescens and green abalone Haliotis fulgens (Haliotidae) were introduced into China from California, USA, and is been cultured experimentally. The red abalone is much bigger than the local abalone. A species of freshwater mussel Hyriopsis schiegeril (Unionidae) was introduced into Shanghai from Japan in 1982. The quality of freshwater pearls cultured from this species was probably better than those of local ones. Ampullarius gigas (Ampullaridae), indigenous to Brazil, was introduced into southern China via Hong Kong in 1982. It has been cultured in ponds, concrete tanks and ditches.

Amphibia American bullfrog Rana catesbiana, indigenous to America, was introduced into China from Cuba in 1962. It has been cultured in parts of China. The natural distribution of the bullfrog is in swamp regions in Hunan Province and Xinjiang Autonomous Region. These frogs have now become established.

Seaweeds (Algae) The kelp Laminaria japonica (Laminariaceae), indigenous to Japan, was accidentally introduced into China. In 1927, it was found growing off the coast of Dalian in northern China. It is theorized that zoospores attached to lumber rafts and to the bottom of cargo boats from 38 northern Japan, settled off Dalian. The first success in experimental culturewas achieved in 1949. The species is cultured throughout China, especially in Zhejiang and Fujian Provinces,as a food and a source of iodine. Yields of 250,000 i/year dry weight have been obtained. A species of giant kelp, Macrocystis pyrifera, was introduced into China from Mexico in 1978 and United States in 1984, respectively. It has been experimentally cultured insome coastal areas of Liaoning and Shandong Provinces. Eucheuma sp. (Solieriaceae), indigenous to the Philippines, was introduced into China in 1985. It has been experimentally cultured in some coastal regions of Shandong Province. Besides these species of seaweeds, Porphyra nereocystis, Porphyra toru, Porphyra meniniata and Porphyra perforata were introduced into Shanghai from the United States in 1985, but none has established.

Discussion Most of the exotic aquatic food species were introduced by research in:;titutes and universities in China, especially after 1950s. The ecological information and culture techniques of species were collected and studied; the advantages and unfavourable characteristics of exotic species were evaluated in detail prior to introduction. The species were quarantined and disinfected prior to introduction. After introductions, the exotic species were confined and cultured in experimental fishfarms in which intensive research on introduced species is undertaken before distributing them throughout the different provinces. Moreover, many species are indigenous to the tropics and are unable to tolerate the low temperature in winter in most parts of China, and the coidwater species cannot tolerate the water temperature in summer. As a result most exotic species have not caused seriou; ecological problems in natural waters. Some species such as Carassius auratus cuvieri are self-reproducing in natural waters and species such as Oreochromis spp. are easily bred under hatchery conditions. They have resulted in an increase in production and contributed to China's fisheries significantly. Fish feed supply is an outstanding problem in China's culture fisheries. The further development of fish culture has been limited by shortage of fish feed, especially those basedon animal food sources. Therefore, among the exotic fishes which have been introduced into China, the omnivores and plankton feeders have been popularized quickly and widely. But carnivorous fish such as Micropterus salmoides are not easily spread althoughsome can consume dead animal matter. It is more difficult to culture the native carnivorous fish Siniperca chuatsi, which feeds on live fish. Research on introductions will be continued; more attention should be paid to quarantine aspects so as to avoid the introduction of new diseases.

Acknowledgements We are greatly indebted to Prof. Q.W. Meng for her encouragement, help and eonstructive suggestions. We should like to thank Prof. S. Q. Wang, Prof. J.X. Su, Mr. W.T. Wang and Mr. G.J. Ling for their valuable information. 39

Relevant Literature

Cheng, T.H. 1969. Production of kelp - a major aspects of China's exploitation of the sea. Economic Botany, 23(3): 215-236. Fisheries Bureau of the Ministry of Agriculture of China. 1986. Some technical information on the exotic species of aquaculture. Kuang, Y.T. and S.H. Liang. 1988. Ornamental fishes and culture. Guangdong Scientific and Technological Publishing House. Tong, H.Y. 1988. Recent development of China's inland fisheries. Manuscript submitted to the Fourth Session of IPFC working pasty of experts on inland fisheries, Sept. 1988, Kathmandu, Nepal. Zhang, Z.H. 1985. Tropical fishes. Beijing Publishing House. Zheng, W.B. and J.H. Pan. 1988. A newly introduced fish, Punlius gonionotus, for freshwater cultivation. Journal of Freshwater Fisheries 143: 3- 7. 40

Table 1. The exotic aquatic food species introduced into China.

Scientific name Common name Origin Year

Pisces CYPRJMDAE Carassius auralus cuvieri Silver crucian catp Japan 1976 Punlius gonionolus Thai silver carp Thailand 1986 Catla calla Catla Bangladesh 1973 Labeo rohita Rohu Thailand 1978 Cypriniss carpio Scattered mirror carp F. Germany 1982 Aischgruhaer via Japan 1984 SERRASALM]DAE Colossoma bidens Freshwater pompano S. America 1985 via Hong Kong

CLARIIDAE Clarias batrachus Walking catfish Thailand 1978 C. macrocephalus Catfish Thailand 1982 C. lazera Leather catfish Africa 1981

PANGASIDAE Pangasius sutchi Stripped/catfish Thailand 1978

ICTALURIDAE Ictalurus punctatus Channel catfish USA 1984 1. nebulosus Brown bullhead USA 1984 SALMONIDAE Sairno gairdneri Rainbow trout N. America 1959 via D.P.R.Korea Donaidsons super USA 1983 rainbow trout Coregonus peled White fish USSR 1985 via Japan Coregonus sp. USSR 1985 via Japan CICHUDAE Oreochromis mossambicus Mozambique tilapia Indonesia 1957 via Vietnam 0. niloticus Nile tilapia Africa 1978 via Hong Kong 0. aureus Blue tilapia Africa 1981 via Hong Kong Sarotherodon galilaeus Africa 1981 Tilapia zulu Red belly tilapia Africa 1981

CENTRARCHIDAE Micropterus salnwides Largeinouth bass N. America 1983 via Hong Kong CRUSTACEA ASTACIDAE Procambarus clarkii Red crayfish N. America 1940? via Japan PALAEMONIDAE Macrobrachiu,n rosenbergui Giant freshwater prawn Thailand 1976 via Japan MOLLUSCS HAUOTIDAE Haliotis rufescens Red abalone USA 1985 H.fulgens Green abalone USA 1985

Continued 41

Table 1. Continued

Scientific name Common name Origin Year

OSTREIDAE Cra.raoslrea gigas Pacific oyster Japan 1979

PECTINIDAE Argopecten irradians Bay scallop USA 1982

IJNIONIDAE Hyriopsis sch!egerii Freswater mussle Japan 1982

AMPULLARIDAE Ainpullarius gigas Giant snail Brazil 1982 via Hong Kong AMPHIBIA Rana catesbiana American bullfrog Cuba 1962

ALGAE (seaweeds) LAMINARIACEAE Laminariajaponica Kelp, konbu Japan 1927

LESSONIACEAE Macrocystispyrfera Giant kelp Mexico 1978 USA 1980 SOLIERIACEAE Euchewna sp. Philippines 1985

BANGIACEAE Porphyra nereocyst is Layer USA 1985 P. torta Layer USA 1985 P. miniata Layer USA 1985 P.perforata Layer USA 1985 42

Table 2. The preliminary list of aquarium fish introduced into China.

Scientific name Common name Origin

OSTEOGLOSSIDAE Osteoglossum bicirrhoswn Arawana S. America CYPRIMDAE Barbus tetrazona Tiger barb Indonesia B. conchontus India B. nigrofasciatus Red ruby Sri Lanka Brachydanio rario Zebra danio India, Bangladesh Brachydanio albolineatus Pearl danio Bumia, India Danio ,nalabaricus Giant danio Sri Lanka, India Punt ias oligolepis Checkered barb Indonesia P. titteya Cheny barb Sri Lanka Labeofrenalus Redtailed Thailand bicolor Red-tail shark Thailand Rasbora heteromorpha Hariguin rasbora, red Thailand R. ,naculata Rasbora Indonesia R. pauciperforata Indonesia Epalzcorhynchuy kallopteru.s SE. Asia CHARACIL)AE Hyplsessobrycon inriesi Neon tetra Amazon H. caldinalis Cardinal tetra Amazon H. herbertaxeirodi Black neon tetra Brazil H. pulchripinnis Lemon tetra Amazon H. heterorhabdus Flag tetra Amazon H. callistus serpae Serpae tetra Amazon H. callistw.s rosaceus Amazon H. flammeus Brazil H. scholzie Black-band tetra Amazon Hemigrammus costello Amazon H. ocelljfer Head-tail light Amazon H. pulcher Pretty tetra Amazon H. rhodostomiss Red-nosed tetra Amazon H. caudoviutalus Argentina Anoptichthysjordani Blind caxe fish Mexico Gymnocoryi'n bus ternetzi Black tetra Bolivia Poedilobrycon unfasciauus One-line pencil fish Amazon Tyayeria sancuaemariae Penguin fish Amazon Alestes longipinnis Africa Aphyocharax rubripinnis Blood fin fish S. America Arnoldichihys spilopterus Nigeria Cheirodon axeirodi S. America Copeina arnoldi Amazon Anostomus anostomus Guyana Pristella riddlei X-ray fish Amazon Phenacogrammus interrupt us Congo Prionobramafiligera Translucent bloodfin Amazon SYNODONTIDAE Synodonuis nigrivenuris Updide-down catfish West Africa POECILIIDAE Poeciloa reticulatus Guppy S. America Molleiensia letipinna Black molly Mexico velifera Sailfin molly Mexico Xiphophoru.s helleri Red tuxedo swardtail Mexico X. macu!at us Moon fish, red platy Mexico X. variauus Vanatus platy Mexico Heterandria formosa USA Gambusia affinis Topminnow, mosquitofish N. America

Continu xi 43

Table 2. Continued

Scientific name Common name Origin

CYPR1NODONTIDAE Aphyosemion bivitlaiwn Red lyretail W. Africa A. australe W. Africa A. gulare Nigeria A. sjoestedti Cameroon Aplocheilus lineal us India, Sri Lanka Jordanellafloridae N. America Epiplatys chaperi Liberia HEMIRHAMPHIDAE Derrnogenys pusillus Halfbeak Singapore Sumatra TOXOTIDAE Toxotesjaculator Archer fish India, Malaysia CICHLIDAE Plerophyliwn eimeki Angel fish Amazon P. scalare Angel fish Amazon Symphysoson dircus Discus Amazon Etroplus macuiat us Orange chromid S.E. Asia A.stronotus ocellatus Tiger oscar Amazon Cichlaso,na meeki Fire-mouth cichlid Mexico, Guatemala C. severum Banded cichlid Venezuela Apislogramma ramirezi Dwarf cichlid S. America A. agassizi S. America Aequidens maroni S. America Haplochromis multicolor Nile Pseudotropheus auratus C. America Pelmatochro,nis kribensis W. Africa CENTEROPOMIDAE Chanda ranga Glass fish Thailand, Bunna Gynochandanfilamentosa India, Buima Elassoma evergladei USA Mesogonistius chaetodon USA ANABANTIDAE Betta splendens Siamese fighting fish Thailand, Singapore Helostoma rudoiphi Kiss gouramy SE. Asia Trichogasler trichopterus Blue gouramy Thailand, India T. trichopterus sumatranus Mable gouramy Indonesia T. leeri Pearl gouramy Thailand Colisa la/ia Dwarf gouramy India C. labiosus Thich-lipped gouramy India, Bunna Trichoopsis pumilus Thailand Spacrichihys osphromenol Indonesia Colisa chuna India TETRAODONTIDAE Tel raodon schoutedeni Green puffer, spotted India, Thailand puffer

Impact of Exotic Aquatic Species in Indian Waters

H.P.C. SHETTY M.C. NANDEESHA College of Fisheries University of Agricultural Sciences Mangalore - 575002 A.G. JHINGRAN Central Inland Capture Fisheries Research Institute Barrackpore - 743101 West Bengal

Shetty, H.P.C., M.C. Nandeesha and A.G. Thingran. 1989. Impact of exotic aquatic species in Indian waters, p. 45-55. In S.S. Dc Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines.

A number of food, game, larvicidal and ornamental fishes have been introduced into India since over a centusy. Of more than 300 exotic species introduced into the country, the majority are aquarium fishes. Among the food fishes the majority belong to the cyprinid group, the prominent among which are the common, silver and grass carps. Grass carp has proved useful both as a culture fish and as an effective biological agent for weed control. Accidental entry of silver carp into Gobindasagar reservoir has resulted in decline in the production of Indian major carps, as well as in total catch. The bighead, introduced recently through private trade is also causing serious concern. The Java tilapia, Oreochromis mossambicus, is considered a pest, though it continues to form a commercial fishery in some reservoirs and is also cultured in some parts of the country. Some of the salmonids introduced into the country have peiformed well and are gaining increasing popularity. Among the molluscs, the giant African snail holds promise for export, while posing a pest problem in certain regions. The accidentally introduced fouling bivalve Mytilopsis sallei is causing grave concern. Water hyacinth and Salvinia are the two exotic plants which have become a major menace in the fishery waters of the country.

India, with its very extensive freshwater resources, has a wide spectrum of native aquatic fauna and flora. All the same, there have been introductions of several exotic aquatic species into the country since over a century. Early introductions mainly consisted of game fish, food fish of minor importance and larvicidal fish. In the post-independence era, a number of cultivable fishes have been introduced with the objective of increasing production from aquaculture. Apart from these, innumerable ornamental fishes have also been introduced into the country at different times. Though these introductions have helped to widen the species spectrum, their impact on indigenous icthyofauna in capture and culture fisheries has not been properly evaluated until now, eventhough it has been realized that some of the introduced fishes have adversely affected the indigenous species. Apart from fishes, a large number of aquatic plants have also been introduced into the country and a few of them also have severely damaged the fishery waters. Therefore, an assessment of the present status of such introductions is urgently needed.

45 46

Present Status of Exotics in India The major exotic introductions and their impact on the indigenous fauna in ,eneral and aquaculture in particular, are dealt with in the following section and are listed in Tabls 1 and 2.

Food Fishes Trout

The areas around the Himalayas in the north and the peninsular hilly regions in the south are temperate in climate, and suitable for the culture of cold water fish. The first attempt to introduce trout as a sport fish was made in 1863 by Francis Day in Nilgiris of peninsular India. However, rainbow trout (Salmo gairdneri) from Sri Lanka, Germany and New Zealand were the first salmonids to be established in many streams of Nilgiris. The submergence of a number of trout streams in the newly formed reservoirs and increasing pollution of the remaining s'ieams have led to a sharp decline in the trout fishery in the post-independence era. In an attempt to improve the trout fishery efforts have been made to introduce some new species such as brown trout and tiger trout (hybrid between brown trout and eastern brook trout (Salvelinusfontinalis) and sockeye salmon (Onchorhyncus nerka). Among the various species of trout introduced in Nilgiris so far, only the rainbow trout has survived under the existing climatic conditions. It appears that trout culture is no longer an economical proposition in NiIgiris region due to pollution of streams and serious disease problems (Sreenivasan et al. 1988). Similarly, in the Himalayan region, introduction of trouts commenced after nearly three decades of their introduction in the Nilgiris region. Of all the introductions into the Himalayan region only brown trout provides a fishery on a commercial scale in streams (Sehgal 1988). Though attempts are being continued to establish trout populations in the cold regions of northern and eastern India, the success is not always commensurate with the efforts, largely due to stocking of undersized fish and the increasing pollution of streams. However, in some high altitude lakes, like Deodital of Central Himalayas, the brown trout has established itself and is breeding naturally (John and Prasad 1988). According to Jhingran and Sehgal (1978), altogether 719 km of trout streams are available in the country, in addition to over 4000 ha of natural and man-made lakes with trout ?opulations. The analysis of creel census data provided by the anglers has revealed that the brown trout catches were around 608-640 g/rod/hr/km fishable length in the Himalayan region in 1971, while in the Nilgiris in the south, the catch was about 457 g/rod/hr/km during 1966-68 (Jhingran and Sehgal 1978). As compared to some other introduced fish species, the trout have remained non- controversial because of their restricted distribution and lack of indigenous cold water sport fishes. The populations of Schizothorax spp. do not appear to have been adversely affected by the presence of trout.

Golden carp

The crucian carp or golden carp (Carassius carassius) was introduced into India in 1874 in the Ooty lake at Nilgiris. The fish thrived well in Nilgiri waters and formed an important fishery 47

Table 1. Salinonids introduced into India.

Common Name Scientific Name Year of Country of Introduction Origin

Brown trout Salmo fru!tafario 1863-1900 U.K. Loch Leven trout Salmo 1evensac 1863 U.K. Rainbow trout Salmo gairdneri 1909 Sri'Lanka, Germany, New Zealand Rainbow trout Salnw gairdneri 1968 Japan (Golden variety) Tiger trout Salmo truttafario 1969 Japan SalvelinusfontinalLs Sockeye salmon Onchorhyncus nerka 1970 Canada Albino trout Sairno gairdneri 1974 Japan Steelhead trout Salmo gairdneri- U.K. & Sri irideus Lanka Rainbow trout Salmo gairdneri 1941 U.K. (Shasta strain) shasta Eastern brook Salvelinusfontinalis Canada trout Splake trout Salvelinus namaycissh- Canada x SalvelinusfontinalLr Atlantic salmon Salmo solar North America

Table 2. Introduced food and larvicidal fishes into Indian waters.

Common Name Scientific Name Year of Country of Introduction Origin

Golden carp Carassiiss carassius 1870 U.K. Tench Tinca tinca 1870 U.K. Gourami Osphronemus goramy 1865 Mauritius 1916 Java Scale carp Cyprinus carpio var 1939 Sri Lanka comniunis Mirror carp Cyprinus carpio var 1939 Sri Lanka specularis Leather carp Cyprinus carpio var 1939 Sri Lanka nudus Bangjcok strain Cyprinus carpio var 1957 Thailand communis Silver carp Hypophtha!michthys 1959 Japan ,nolitrix Grass carp Ctenopharyngodon 1959 Hong Kong idella Tawes Puntisssjavanicus 1972 Indonesia Java tilapia Oreochronric 1952 Thailand & mossambicus Sri Lanka Nile tilapia Oreochromis niloticus Bighead carp Aristichthys nobilis Barbados millions Lebistes reticulatiss 1908 South America Top minnow Gambusia affins 1928 Italy 48 for a few years. The species attains over one kg in weight and breeds in ponds, like common carp. However, with the introduction of common carp, with which it shares a common habitat, the fishery of golden carp has dwindled drastically.

Common carp

The Prussian strain of common carp introduced in Nilgiris in 1939 from Sri Lanka consisted of three varieties (Table 2). Since the Prussian strain was mainly suited for cul:ure in cold climates, the Bangkok strain of common carp was introduced from Bangkok in 1957 for culture in plains. However, both strains are now widely cultured throughout the country. The common carp is one of the species usually included in composite carp culture in India. Its proportion varies from 10-30%, depending on the type of culture. The food habits of common carp are similar to those of mrigal (Cirrhinus mrigala), a species commonly included in composite culture. The common carp has been found to be more suitable for sesona1 water bodies. Under Indian conditions, the fish attains an average weight of 0.6-1.0 kg in the first year and matures when it is just 6-8 months old. It breeds naturally even in impoundments. Even though common carp has been introduced into most of the reservoirs and lakes in the country, it is well established only in a few of these water bodies. On the other hand, it is believed that the common carp is responsible for the sharp decline in the abundance of Schizothorax spp. in Dal Lake in Kashmir and Osteobrama belangeri in Loktak Lake in Manipur (Das 1988).

Silver carp

The silver carp, Hypophthalmichthys molitrix, was introduced with the objective of filling up a vacant ecological niche in the pond culture system (Tripathi 1958). This fish occupies the surface - column zones of a pond and feeds voraciously on phytoplankton. In its native habitat in China, it matures in 4-6 years (Kuronuma 1968), but does not breed naturally even after hormone injection in India and needs to be stripped about 6-8 hr after the second injection. The silver carp has become one of the major controversial species in Indian aquaculture. Though the species was considered to be ecologically non-competitive with Indian major carps, long experience in culture has shown that it competes with catla to some extent. The species is usually stocked at 20-30% in composite culture, and its contribution to total production is usually higher than its stocking percentage. Its poor keeping quality and market value, coupled with its competition with other species, have raised some doubts about itssuitability in composite culture. Apart from its declining popularity in culture practices, the species has caused concern to ecologists by its presence in Gobindasagar (10,500 ha) reservoir in Himachal Pradesh. From 1974 the silver carp started appearing in increasing numbers and in 1986-87 it contributed 46.5% to the total catch (Table 3). This clearly indicates that the species has established itself in the reservoir. Significantly, with the increasing contribution of silver carp, catla and rohu catches have declined sharply. In addition, the total catch of the reservoir has also declined, possibly indicating the negative effect of silver carp on other fish. The introduction of silver carp into Kulgarhi reservoir has led to similar resulis (Natarajan 1988). 49

Grass carp

The grass carp, Ctenopharyngodon idella, was introduced mainly for purposes of biological control of submerged aquatic vegetation in fishery waters, in particular Hydrilla, Vallisneria and smaller floating weeds like Lemna sp. However, because of its fast growth rate, it was very soon included as a component in composite fish culture. It does not usually breed naturally even after hormone injection and therefore has to be stripped. It feeds on aquatic weeds and more voraciously on soft aquatic vegetation like Hydrilla, but does not feed on Eichhornia, Pistia and Salvinia (Singh et al. 1967) and grasses and leaves of leguniinious plants. The grass carp has been widely used in the country for weed control in canals (Kulshreshthra and Sharma 1976; Singit, pers. comm.), water cooling tanks (Chaudhuri et al. 1976) and ponds (Keshavanath and Basavaraju 1980). In composite culture systems, the grass carp lends an added advantage in that it consumes vegetation more than its own body weight and voids most of it in semi-digested form, which serves as food for omnivorous fishes and also as pond fertilizer. The introduction of grass carp, therefore, has proved beneficial.

Tawes

The Tawes, Puntius javanicus, is known to be macrophagous, and is cultured in only some parts of the country. It breeds naturally and attains a weight of over one kg in a year. However, the species is not popular in culture practices in India.

Tench

The Tench (Tinca tinca) introduced into Nilgiris in 1874 is established well in the Nilgiris region and individuals weighing over 1 kg can be caught from Ooty Lake. It matures in the 2nd or 3rd year and breeds under pond conditions. However, recent reports indicatethe disappearance of the tench from Nilgiris waters (Sreenivasan et al. 1988).

Bighead carp

Bighead carp (Aristichthys nobilis) were accidentally introduced into India (Das 1988), where they remained confined to the fish farm of Central Inland Fisheries Research Institute at Cuttack and later disappeared altogether. They have reportedly reappeared in the country in 1987, presumably through private trade from Bangladesh. Jhingran (1985) has discussed in detail the likely consequence of the introduction of bighead to Indian waters. Its feeding habits are similar to that of catla and is likely to pose a threat to catla. The suitability of bighead is yet to be assessed in terms of consumer preference, growth rates under Indian conditions and disease resistance. 50

Gourami

The gourami Osphronemus goramy, an anabantid, has been cultured in several states for nearly four decades, but with little success. Because of its slow growth, it is no longer actively cultured anywhere in the country. However, it has established itself in waters in some parts of peninsular India. Because of its nest building habit, the rate of survival of its progeny is high. Being phytophagous, it also serves to control aquatic weeds to some extent.

Tilapia

The Java tilapia Oreochromis mossambicus, a cichlid, is the most controversia among the exotics in India. Apart from the official introductions, this fish has also found its way into the country through unofficial transplantation from Bangladesh by private entrepreneurs. Even though the Government of India has never advocated the commercial culture of tilapia and its introduction into natural water bodies, it has spread to several parts of the country and has even established itself in some reservoirs (Sukumaran and Tripathi 1988; Chandrasekeran and Sreenivasan 1988). A number of factors has led to overpopulation and stunted growth. Though the fish has been found to feed predominantly on phytoplankton, in the absence of :Lts preferred food it tends to be an omnivore and sometimes even a carnivore (Jhingran 1974). Tilapia was cultured with encouraging results during the initial stages, production ranging from 2000-10,000 kg/ha/yr (Chandrasekaran and Sreenivasan 1988). The catches from a few reservo:Lrs in Tamil Nadu are given in Table 4 and it is apparent that there is a general decline in tilapia catches over the years. It is quite difficult to eradicate this fish from where it has already gained a permanent foothold (Natarajan 1988; Jhingran 1988). It is reported that another species of tilapia, 0. niloticus, has already been introduced through private trade in West Bengal and is being cultured in sewage-fed farms. Table 3. Catch composition in Gobindsagar Reservoir (in tonnes; percentages are given in parentheses).

Year Total Common Catla Silver (t) carp carp

1976-77 546.6 81.10 142.12 8.00 (14.80) (26.00) (1.46) 1977-78 706.8 135.03 169.01 10.00 (19.23) (29.91) (1.41) 1978-79 754.6 176.53 101.92 13.17 (23.39) (13.50) (1.74) 1979-80 715.8 222.76 40.68 43.66 (29,72) (5.68) (6.09) 1980-81 707.9 176.03 69.34 88.53 (17.59) (8.28) (14.68) 1981-82 653.4 114.99 54.11 95.89 (17.59) (8.28) (14.68) 1982-83 561.8 130.53 26.96 102.58 (23.30) (4.79) (18.25) 1983-84 425.6 119.46 25.41 107.08 (28.06) (5.97) (25.15) 1984-85 505.5 91.41 41.97 223.34 (18.08) (8.30) (44.18) 1985-86 546.5 122.81 29.81 244.34 (22.47) (5.45) (44.70) 1986-87 377.1 71.06 19.94 176.32 (18.84) (5.29) (46.76)

(Source: Kuldeep Kumar, personal communication) Table 4. Total catch and tilapia yield (in tonnes) in some reservoirs of Tamilnadu.

Year Total Amaravathy Tilapia Total Vaigai Tilapia Total Bhavanisagar Tilapia Total Tirumoorthy Tilapia Total Upper Dam Tilapia Total Krishnagiri Tihipia 79-8078-7977-78 145.7149.6197.79 139.97(95.86)(87.93)85.99 -ND- -ND- 14.34 5.775.15 (87.96)(80.47)11.54 3.914.53 29.30 -ND- (42.22)12.37 -ND--ND- 81-8280-81 160.39 73.88 147.18(88.45)(82.73)62.3541.04 26.78 4.83 -ND- Nil 267.60321.20 -ND- Nil 5.565.56 (68.76)(68.34) 3.923.80 56.5 120.35 50.20 (7 2.49)(64.74)32.5087.2415.50 -ND- 83-8482-83 124.79 80.60 105.78(84.77)(91.76)64.00 41.0415.93 Nil 300.35 57.80 (0.72)Nil2.16 15.0810.80 (33.82)(70.50) 5.103.50 50.05 6.38 (40.38)20.21(27.3 9) 0.39 30.3545.79 -ND- (3.79)1.151.26 85-8684-85 427.00 20.88 341.60(80.00)(79.40)10.35 -ND---ND- 175.67134.00 (13.82)24.2718.46 12.27 5.80 (21.55)(32.40) 1.501.25 10.90 5.22 (39.54) 2.294.31(6.11) 48.0634.42 (3.52)1.63(2.75)1.21 87-8886-87 36.57 -ND- (22.99)(49.57) 8.41 26.48 -ND- (4.38)1.16 133.4967.76 (19.07)(13.78)12.92(15.10)20.16 23.41 -ND- (12.22) (0.05)1.26 12.5615.24 (23.96)(43.87)(53.74)3.018.19 41.5950.05 (13.01)(20.92)10.475.41(3.39)

(Source: Sreenivasan, pers. comm.); ND - No data; Figures within parentheses indicate percentage contribution to total catch. 52

Larvicidal Fish The poeciliid Lebistes reticulatus was introduced for mosquito control. It is reported that one more species of larvicidal fish, Notobranchus sp. has also beenintroduced (Sreenivasan et al. 1988). However, these fish have not been widely employed for the purpose they were introduced. On the other hand, Gambusia affinis is known to adversely affect the fishery of other fishes by preying on their spawn. In Ooty Lake, this fish severely affected the mirror carp fishery and only after its eradication, the mirror carp fishery could be reestablished.

Ornamental Fish A large number of ornamental fish, consisting of both egg layers and live bearer;, have been introduced into the country over the years. Baskar et al. (1988) have reported the presence of 261 species of exotic egg layers in India. However, they contribute about 25% to the country's export trade, which is dominated by the domestic egg layers. Subramanian et al. (1988) listd a total of 27 exotic live bearers in India. A number of different strains are reported to exist within these. Exotic aquarium fishes are considered important from the view point of developing export and domestic trades.

Molluscs

Mytilopsis sallei This exotic bivalve, which is native to Central American region, appears to have been brought into Indian waters through ship fouling in the late 1960s. It has become a major fouling pest, gaining almost monospecific dominance in fouling communities, with abiornass build up of to 100-120 kg/m-2/yr. This bivalve is also seen in large numbers in Kakinada harbour, but only to a small extent in Bombay Harbour. It appears highly probable that this fouling organism will pose a serious problem in the country (Rao et al. 1988).

Aquatic Plants

Over the last century, several aquatic plants have been introduced into the couniry, but a full list of these is not readily available. However, only a few of them are of importance from a fisheries point of view in that they have proved harmful. Foremost among them is the water hyacinth (Eichhornia crassipes), which was reportedly brought from Australia for its flowers. This fast growing weed has become the single biggest menace in fishery waters and navigation channels. Even though effective mechanical and chemical methods for eradication of this weed are known and also practised off and on, failure totake suitable follow-up measures has invariably led to reinfestation. Its growth is particularly pronounced in waters receivLng domestic sewage. Recent experiments have shown the possibility ofbiological control of this weed using the insect Neochitina eichhorniae (Jayanth 1987). Some recent studies have indicated the possibility of useful utilization of this obnoxious weed, such as in bio-gas production (Joglekar and Sonar 1986), and fish feed (Anil et al. 1986). 53

Salvinia molesta, a floating fern of South American origin, is another obnoxious weed infesting the Indian fishery waters. It was earlier noticed only in the backwaters of Kerala, but is now slowly spreading to other areas. Though it has been demonstrated that this fern could be controlled easily by spraying aqueous (1-2%) ammonia, the technique is not used widely because of certain inherent limitations. However, recent investigations have indicated the possibility of complete elimination of this weed using the insect Cyrtobagous salviniae (Jayanth 1987; Joy et al. 1985). Pistia stratiodes and Ipomea carnia, both of south American origin, are the two other obnoxious exotic weeds. Even though the present extent of infestation is much less compared to water hyacinth and Saivinia, there is need to contain it before they too pose a serious threat to fishery waters. As it is, 2-4 D has been found to be effective in controlling these weeds (Ramachandran and Prabhu 1988).

Conclusions and Recommendations

The deliberations of the Indian Branch of the Asian Fisheries Society at its Workshop on Exotics, April 1988, form the main basis for the conclusions and recommendations listed below. The Chinese carps have helped in increasing fish production to 10 t/halyear from composite fish culture, involving three Indian major carps and three exotic carps. However, as compared to the Indian carps, the consumer preference is rather low for the exotic carps, particularly the silver carp, because of its poor keeping quality. It is now known that silver carp competes with catla for food to some extent. The Chinese grass carp has proved most useful and efficient in the biological control of submerged weeds. It has also proved to be a good table fish. Under Indian conditions, it grows fast and can easily be maintained on any of the submerged aquatic weeds, terrestrial grasses and leaves of leguminous plants. The accidental introduction of silver carp into a few reservoirs has led to a sharp decline in the catla population, as well as total fish production. As the Prussian strain of common carp is the only species of exotic carp that can do well in upland waters, more emphasis is required to be given for its propagation in upland waters. In water bodies where tilapia has already gained a firm foothold, it should be possible to reduce its numerical dominance by continuous stocking of these water bodies with major carps. Some other species of tilapia are known to have better cultivable qualities than Oreochromis mossambicus. It may be desirable to consider introduction of some species into India purely for experimental purposes, to assess their suitability for culture under Indian conditions either by themselves or through the production of hybrids. There does not appear to be a need to introduce any new salmonids. Instead, good hatchery facilities should be developed for the existing species and more attention given to their genetic improvement, and prevent degradation of the ecology of trout streams because of pollution. Instead of introducing a number of species for different purposes, improvement of the genetic quality of the indigenous major carps should be given more attention. It is also necessary to regulate the introduction of exotic species into neighbouring countries,suchas Nepal, Bhutan, Pakistan and Bangladesh through existing regional organizations, since such introduced species could easily cross over into Indian territory. 54

Some of the exotic aquarium fishes have established themselves very well in the country and have a good export demand. Therefore, it is imperative to initiate research on their breeding and mass culture to boost the export trade. A number of exotic aquatic weeds have already become a nuisance in the country's fishery waters. Concerted effort should, therefore, be made to develop suitable methods for their control and utilization. The reported illegal entry of fishes, such as the bighead carp and Oreochrornis niloticus into the country is required to be viewed seriously. Until such time that their utility i.s proven in controlled experiments, their trade and culture should be banned. No exotic fish, however successful elsewhere, should be introduced into Indian waters without first ascertaining their utility under controlled conditions. Even if an exotic fish competes with a commercially important indigenous fish, if in all respects the former is proven to be better such introductions could be possibly permitted, but steps must be taken to ensure that the indigenous species is not endangered. All introductions of exotic species must be controlled by a central agency like the Ministry of Agriculture, Government of India or the Indian Council of Agricultural Research and no private agency should be permitted to import exotic species. At present, there is no proper quarantine procedure in respect of fish impor:ations. The common diseases now encountered in trout farms, viz. 'whirling' disease caused by Myxosoma cerebra/is and'ich'disease caused by Ichthyophthirius multifihisare of exotic origin (Sreenivasan et al. 1988; Sehgal 1988). Similarly, the origin of a few parasites like Tripartiella spp. and Neoergasilus japonicus are traced to Chinese carps (Das and Halder 1988) Therefore, there is an urgent need to develop suitable quarantine facilities and to lay down a proper quarantine procedure.

References

Anil, K., I.P. Keshavanath and M.C. Nandeesha. 1986. Water hyacinth as a substitute for fish meal in carp diet. Paper prsented at the 7th International Symposium on Aquatic weeds, 15-19 September, Loughborough, England. Baskar, S.L, P.S.R. Reddy, B. Subramanian and RJ. Lazanis 1988. Exotic freshwater aquarium fishes and their role in the aqusrium fish trade of India I. Egg layers. Paper presented at the workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore. Chandrasekaran, A. and A. Sreenivasan. 1988. Introduction of tilapia in Tami]nadu. Ibid. Chaudhuri, H., D.S. Murthy, R.K. Dey and P.V.G.K. Reddy. 1976. Role of grass carp, Ctenopharyngodon idella (Val.) in biclogical control of obnoxious aquatic weeds in India: a review, p. 3 15-322. In C.K. Varshney and J. Rzoska (eds.) Aquatic weeds in South-east Asia. Dr. W. Junk Publishers, The Hague. Das, P. 1988. Exotic fish germplasm resources in India and their conservation. Paper presented at the Workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore. Dat, M.k. and D.P. Halder. 1988. Parasitc fauna of cultured exotic carps in India: its biological significance. Paper presented at the Workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore. Ghosh, A., L.H. Rao and S.K. Saha. 1980. Culture prospects of Saroiherodon mossambicus in small ponds fertilized with lomestic sewage. Journal Inland Fisheries Society, India 12: 74-80. Ghosh, A., A. Ghesh, P.K. Chakraborthi and G.N. Chattopadhyay. 1988. Later calcarifer as a biocontrolling agent for Oreochi-mis mossambicus in sewage-fed impoundments. Paper presented at the Work shop on Exotic Aquatic Species in India, 25-26 April, Mangalore. Jayanth, K.P. 1987. Suppression of water hyacinth by the exotic insect Neochitina eichhorniae in Bangalore, India. Current Science 56: 494-495. Jayanth, K.P. 1987. Biological control of the water fern Sal vinia ,nolesta infesting a likely pond in Bangalore (India) by Cyrtcbagous salviniae. Entomophaga 32: 163-165. Thingran, A.G. 1984. Some considerations on introduction of tilapia into Indian Waters. Bulletin Bureau Fish Genetics Research, 34 p. Jhingran, A.G. 1985. The scope and limitations of introducing the bighead carp Aristichthys nobilis (Richardson) in inland waters of India. Bulletin Bureau Fish Genetics Research, 18 p. Thingran, A.G. 1988. Status of exotic fishes in Indian capture fishery. Paper presented at the Workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore. Jhingran, V.K. and R. Prasad. 1988. Impact of introduction of trout (Salrno truttafario and Salmo gairdneri) in Garhwal ]imalayas in India. Paper presented at the workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore. 55

Joy, PJ., K.R. Sathesan and D. Joseph. 1985. Successful biological control of the floating weed Salviniae nwlesta Mitchell using the weevil Cyrtobagous salviniae Sands in Kerala (India). Asian-Pacific Weed Science Society 10th Conference, November 24-30, Chiangmai, Thailand. Keshavanath, P. and Y. Basavaraju. 1980. A note on utility of grass carp, Ctenopharyngodon idella (Valenciennes) in controlling the aquatic weed, Hydrilla. Current Research 9: 154-156. Kulshresthra, S.D. and K.P. Shamia. 1976. Biological control of aquatic weeds in the Chambal Comm and Area of Kota using grass caip, Ctenop/zaryngodon idella (Val.). Joumal Inland Fisheries Society, India 8: 113-114. Kuronuma, K. 1968. New system and new fishes for culture in the Far East. FAO Fisheries Report 5: 123-142. Mishra, B.K., A.K. Sahu and C. Pani. 1988. Recycling of the aquatic weed, water hyacinth and antmal wastes in the rearing of Indian major carps. Aquaculture 68: 59-64. Mitra, A., T.K. Nayak and S.K. Sarakar. 1988. Culture of Oreochromis nwssambicus under different culture system in West Bengal, its social acceptance and economic retum. Paper presented at the Workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore. Natarajan, A.V. 1988. Ecological and aquacultural roles of exotic fishes in aquatic productivity in India. Paper presented at the Workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore. Pandian, T.J. and K. Varadaraj. 1987. Techniques to regulate sex ratio and breeding in tilapia. Current Science 56: 337-343. Ramachandran, V. and T. Ramaprabhu. 1988. Major exotic aquatic weeds in India - present status of knowledge. Paper presented at the Workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore. Rao, K.S., V.V. Srinivasan and M. Balaji. 1988. Spread of the exotic fouling bivalve, Mytilopsis sallei (Recluz) in Indian harbours. Paper presented at the Workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore. Sehgal, K,L. 1988. State-of-art of exotic coldwater fishes in India. Paper presented at the Workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore Singh, S.B., K.K. Sukumaran, K.K. Pillai and P.C. Chakrabarti. 1967. Observations on efficacy of grass carp, Clenopharyngodon idella (Val.) in controlling and utilizing aquatic weeds in ponds in India. Proceedings Indo-Pacific Fisheries Council 12:220-235. Shetty, H.P.C. and M.C. Nandeesha. 1988. Status of exotic aquatic species in Indian waters. Paper presented at the workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore. Sreenivasan, R., P.S.R. Reddy, B. Elambarithy, IS. Baskar and R.J. Lazarus. 1988. Exotic freshwater aquarium fishes and role in the aquarium fish trnle of India. II. Live bearers. Paper presented at the Workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore. Sukumaran, K.K. and S.D. Tripathi. 1988. Oreochromis mossambicus - a controversial exotic Species in Indian waters. Paper presented at the Workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore. Tripathi, S.D. 1988. Silver carp (Hypophthalmichthys molitrix) and grass carp (Clenopharyngodon idella) -- exotic elements in freshwater carp polyculture in India. Paper presented at the Workshop on Exotic Aquatic Species in India, 25-26 April, Mangalore.

Exotic Aquatic Species Introduction into Indonesia

H. MUHAMMAD EIDMAN Faculty of Fisheries Bogor Agricultural University Darmaga Campus, Bogor

Eidman, H.M. 1989, Exotic aquatic species introduction into Indonesia, p. 57-62. In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proecedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines.

The knowledge on the biology of the large freshwater fish fauna of Indonesia is limited. Domestication of endemic species has not been done intensively. Introduction of exotic species started long time ago by the fish traders especially as ornamental fish. Intended introduction of aquatic species in later years was for aquaculture, ornamental purposes and mosquito eradication. Some introductions have been beneficial while others directly or indirectly disturb the ecosystems.

Indonesia as an Indo- Australian archipelago consists of many islands, and spreads between Pacific and Indian oceans. It has a rich flora and fauna. Thispaper will deal mainly with freshwater organisms since introduction of marine organismsislimited, and sparsely documented. The freshwaters of the western part of Indonesia (Sunda region) which includes Sumatra, Kalimantan and Java are inhabited by more than 500 indigenous species of fish, 70 % ofwhich belong to Ostariophysi and Labyrinthici, the dominant freshwatergroups. Eastern Indonesia (Sahul region) which includes Irian Java has more than 100 fish species and is dominated by euryhaline species. Central Indonesia (Wallace region) which includes Sulawesi and the Nusa Tenggara is inhabited by some 50 fish species (Ondara 1982). Even the endemic fish fauna is numerous, but little is known of their life histories, which hampers their domestication. Instead of domesticating the local species, which ofcourse needs more time and effort, people tended to take short cuts by introducing the already domesticated species available in the market. Some species improved the fisheries and aquaculture production while others were a failure.

Present Status of Exotic Aquatic Species in Indonesia

Information on the introduction of fish into Indonesia was reviewed by Schuster (1950). The major introductions are summarized in Table 1. The introductions into Indonesiaare divisible into a number of eras.

57 58 Table 1. Introduced aquatic species into Indonesia.

Date Species Source Remarks

pre 1900 Cyprinus carpio China The exact yeal is not Carassius' auratu.s known, continuously introduced 1915 Ctenopharyngodon Malaysia and Accidental idella, Labeo molitorella Singapore 1920 Lebistes ret kul at us Unknown Malaria eradic ation; unsuccessful 1927 Tinca vulgaris Netherlands Inland Fisheris (tench), Cyprinus Department carpio (Galician race) 1929 Salmo trutta iridea Netherlands Inland Fisheries Depart- (rainbow trout) ment; unsuccessful Salmo Irutla fario (river trout) Salmo salar (salmon) Netherlands Gambusia affinis Unknown Accidental, mixed with Cyprinus carpio Netherlands local varieties (Frankish race) 1934 Trichoga.ster Malaysia Inland Fisheries pectoralis (Regan) Department; Successful (Snake Skin Gouramy) 1937 Salmo truttafario New Zealand Mr. Missegas (river trout) (EnglishmarL) unsuccessful 1939 Salmo trullafario Denmark Collaboration with Inland Fisheries Department Australia Oreochromis Unknown Found in the South mossambicus Peters coast of East Java by Mr. Mudjair 1949 Clenopharyngodon idella Thailand Inland Fisheries Depart- ment, Unsuccessful 1964 Clenopharyngodon idella Japan Introduced by Mr Rustami Djajsdiredja 1967 Hypophthalmkhlhys molitrix Japan ditto 1967 Hypophthalmichthys molitrix Taiwan ditto 1969 Oreochromis nilolicus Taiwan ditto 1969 Arislichlhys nobilis Taiwan ditto 1969 Cirrhina ,nolitorella Taiwan ditto 1972 Pangasius sutchi Thailand ditto 1986 Ictalurus punctalus USA experimental purposes (channel catfish) (RIFF)* 1987 Carassius aural us (Koi) Taiwan experimental purposes

Other Organisms Clarias gariepinu.s Unknown Fish dealer, (catfish) experimental Rana catesbiana Unknown Commercial, not (bullfrog) successful yet Eichhornia crassipes Unknown Wide spread (water hyacinth) Eucheuma cotton ii Philippines As aquaculture species, good results Serrasalmus sp. (pirranha) Unknown Fish trader, exterminated

* REFF Research Institute for Freshwater Fisheries (formerly: Inland Fisheries Department) 59

Early Years

Cyprinus carpio L. and Carassius auratus L.were believed to be the first exotic species introduced into Indonesia. These fishes have been imported from Chinaby ornamental fish dealers. In Malang (East Java) and Bogor (West Java)a number of fish-breeding places were established and some fish probably escaped intoopen waters. Cyprinus carpio importations were continuously done until recently and they have mixed with the olderones. This species became the most common fish cultured in fresh water ponds,cages and running water systems.

The 1920s

Lebistes reticulatus (Peters), guppy is an aquarium fish species whichescaped into ponds and open waters in Bandung, West Java. In warm waters, Lebistes appearedto degenerate in size. They do not feed on mosquito larvae; they are not valuable in mosquito control inJava. Instead, they compete with plankton feeders. Another aquarium fish that escaped to the open waters is Gambusia affinis.However, it has disappeared now. In 1929, the Inland Fisheries Department imported live rainbowtrout Salmo trutta iridea Gibb. from the Netherlands to Indonesia and theywere reared in the mountain area of Malang. The eggs of the rainbow trout (Salmo trutta iridea Gibb.), the rivertrout (Salmo truttafario L.), as well as salmon (Salmo salar L.) were hatched and fry were released into the streams of Kawi mountain in East Java. These fish could not live in warm waters during the dryseason and they have since disappeared altogether. Eggs of Salmo trutta fario L.were imported again from New Zealand (1937), Denmark and Australia (1939), hatched and fry of 15cm were released into mountain streams. However, the attempt was not successful.

The 1930s

The Inland Fisheries Department imported Trichogaster pectoralis (Regan) fromMalaysia. At the beginning it was difficult to breed this species. However, in 1935 breedingwas successful and in 1937 this species began to spread and become economically important.Presently this species is widely cultured in ponds and are also successfully established inopen waters. The occurrence of Oreochromis mossambicus (Peters), the Java tilapia, in Indonesia isstill not clear. This species was caught first in Java by Mr. Mudj air, whosename was later given to it on a suggestion of the Inland Fisheries Department. Due to its adaptability and because it breeds easily, it became one of the most important freshwater fishes in Indonesia. For the small-scale fish farmer and the low incomegroups this species is very useful. However, in more capital intensive aquaculture the Java tilapia is consideredto be a competitor or trash fish. Aside from being a food fish the Java tilapia is also useful for malaria eradication. 60

The 1940s The Inland Fisheries Department imported the grass carp, Ctenopharyngodon idella (C. et V.) from Thailand to Java. The purpose of importation was to study its aquaculture potential. The prospects for grass carp in Indonesia are bright. There are many lakes and other water bodies with abundant aquatic plants that can be utilized by this species.It is used for experimental purposes.

The 1960s The silver carp (Hypophthalmichthys molitrix) was first introduced into Indonesia in 1964 and again in 1969 from Taiwan. Experiments done at the Research Institute for Freshwater Fisheries, Bogor, and the breeding experiments using hypophysation techniques were successful in 1971. Silver carp is a plankton feeder;it grows faster than other plankton feeders (Trichogaster pectoralis and Helostoma temmincki). This species is still used for experimental purposes (Hardjamulia 1978). The purpose of importing this species is to utilize plankton more efficiently. ]However, this species is not yet popular in aquaculture. Oreochromis niloticus was introduced into Indonesia in 1969. Its performance is considered to be better than 0. mossambicus. This species is already spread widelyand is very popular among fish farmers; it is an example of a successfulintroduction of an exotic species in Indonesia. To utilize the natural food available in ponds, it is suggested that this species be cultured in combination with carp and Puntius javanicus or with carp and giant gouramy. In 1969, four species of fish were imported to Indonesia from Taiwan: Hypophthalmichthys molitrix, Oreochromis niloticus, Aristichthys nobilis and Cirrhina molitorellaHardj amulia 1978).

The 1970s Pangasius sutchi Fowler was imported to Bogor in 1972 from Bangkok. Ereeding was successful using hypophysation technique. The prospect of this species for aquacuLture is good. Growth rate is high and it can be cultured intensively (Effendi 1975; Hardjamulia 1.978; Ondara 1982).

The 1980s With the improvement of the economy, fish consumption in the larger cities increased. Besides other fishes, demand on Cyprinus carpio has increased. There is a shift in the method of carp culture from stagnant water ponds and cages to more intensive culturein running water systems. This rush for carp running-water-system culture was suddenly disrupted by the outbreak of haemorrhagic septicemia which started in Cibening near Bogor. The disease is thought to have been caused by Aeromonas salmonicida and Aeromonas hydrophilia in combination with a virus. Other species that became victims of this disease included Osphronemus goramy and Clarias 61 batrachus. It remains uncertain whether the pathogens were brought through fish importations or not. Whatever the cause, this disease outbreak awakened the Government that the introduction of exotic species may have disastrous effects. Outbreaks of this magnitude have not occurred earlier. The measures which have been taken seem to be effective. Channel catfish (Ictalarus punctatus) was imported from the United States for experimental purposes. There is no available information on its suitability for aquaculture in Indonesia as experiments are still in progress (Balitkanwar 1987). Koi (Carassius auratus) was imported from Taiwan for experimental purposes. This ornamental fish is becoming very popular especially in big cities. Breeding so far has been successful (Balitkanwar 1987).

Other Aquatic Organisms Introduced into Indonesia

Clarias gariepinus- imported by fish dealers; became very popular and is called 'lele dumbo".

Rana catesbiana - bull frog (Amphibia), still in experimental stage; commercial scale not profitable due to difficulties in providing proper food (Achatinafulica as feed).

Anodonta woodiana - fresh water mollusc; introduced from Taiwan together with the importation of Oreochromis niloticus and Hypophthalmichthys molitrix. The larvae (Glochidium) use fish as their host (Suseno 1978; Djajasasmita 1979). Eichhornia crassipes- water hyacinth. It has become a nuisance in reservoirs. Mechanical, chemical and biological eradication methods have not been successful. Among others Rawa Pening (Central Java), Saguling Reservoir, Curug Reservoir are infested.

Eucheuma cottonii - seaweed. Cultured together with Eucheuma spinosum which is endemic. Good results were reported in Bali.

Conclusion and Suggestions

Introductions of exotic species are likely to be continued either intentionally or unintentionally for emotional, commercial or ecological reasons.

Studies on the aquatic ecosystems should be encouraged in order to obtain basic information. The impact of introductions can be predicted with additional knowledge of the candidate exotic species.

3. Local aquatic species should be investigated for their suitability for aquaculture and as ornamental fish. 62

Indonesia includes three different areas of fish distribution: the Western area (Sunda region); the Eastern area (Sahul region) and the Central area (Wallace region), with different fish populations and aquatic organisms. Suitability in one place does not necessarily hold for the other parts of the country. Law enforcement, facilities for quarantine, education and extension on the usefulness and danger of careless introductions are necessary. Cooperation and mechanisms between exporting and importing countries to safeguard the success of interchange of aquatic species should be developed.

References

Balitkanwar, A, 1987. Keadaan Kan lele annorika (Hetalurus punctatus) selama Nopember 1986-Manet 1987. Laporain: 2. Balitkanwar Pusitbankan Bahtbangtan Departmen Pertanian. lOp. (In Indonesian). Balitkanwar, A. 1987. Keadaan kam leoi (Carassius auratus) asal Taiwan selama 16 Nopunka-28 Manet 1987. Balitkanwar, Pusitbankan, Balitbangtan, Departmen Pertanian. 7 p. (In Indonesian). Djajasasmita, M. 1974. Bagaimana cara Kijma Taiwan Anodonta woodiana, Lea 1837 dapat menyelundup ke Indonesia. (Flow the Taiwanese clam Anodonta woodiana, Lea 1837 could infiltrate into Indonesia) Buletin Kebun Raya, Vol 1, No. 4, KeburL Raya-LBN- L1P1, Bogor. (In Indonesian). Effendi Momahed Ichsan. 1975. Masalah introduksi jenisikan baru (Problems of the new fish species introduction) WART A PERIKANAN - Communications on Agriculture. No. 33, 5th Year, Department Pertanian, Jakarta, Indonesia, p. 19-21. (In Indonesian) Hardjamulia, Atmadja. 1978. Budidya Ikan Mola (Hypophthalmichthys molitrix), ikan grass carp (Clenopharyngodon idellus), ikan jambal Siam (Pangasiu.s sutchi Fowler) dan ilcan nila (Tilapia nilotica). Untuk sekolah usaha perikanan menengah Budidya Bogor Departmen pertanian BPLPP - SUPM Budidya, Bogor. 33 p. Lecture mimeograph (In Indonesian). Hardjamulia, Atmadja and Rustami Djajadiredja. 1978. Notes on the contributions of introduced species, Tilapia nilotica, and Hypophthalmicthys molitrix, to the development of fishculture in Indonesia. ASEAN meeting of experts on Aquaculture, Semarang, Indonesia, 31 Januaiy-6th Febmaty 1977. 14 p. Ondara, M. 1982. Beberapa cetatan tentang perairan tawa dan fauna iknannya di Indonesia (several notes on freshwater and its fauna in Indonesia) Prosiding simposium perikannan petairan Umum No. 1 - Prosd. No. l/SPPU/82, Departmen pertanian, Jakarta, Indonesia, p. 13-32. (In Indonesian with English abstract) Schuster, W.H. 1950. Comments on the importation and the transplantation of different species of fish mto Indonesia. Contributions Gen. Agriculture Research Station, Bogor, Indonesia, No. 111: 1-31. Suseno, DJOKO. 1978. Kijing Taiwan Anodonta woodiana Lea 1857, (Taiwanese clam Anodonta woodiana Lea 1857). WARTA PERIKANAN - Communications on Agriculture, No. 46, 8th Year, Deparimen Pertanian, Jakarta, Indonesia, p. 9-11. (In Indonesian) Present Status of Aquatic Organisms Introduced into Japan

KENJI CHIBA Fisheries Laboratory Faculty of Agriculture University of Tokyo 2971, Maisaka, Hamana Shizuoka 431-02

YASUHIKO TAKI KIYOSHI SAKA! Tokyo University of Fisheries 4-5-7 Konan, Minato Tokyo 108 YOSHIOKI OOZEKI Dept. of Fisheries Faculty of Agriculture University of Tokyo 1-1-1 Yayoi, Bunkyo, Tokyo 113

Chiba, K., Y. Taki, K. Sakai and Y. Oozeki. 1989. Present status of aquatic organisms introduced into Japan,p. 63-70. In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pub!. 3, 154 p. Asian Fisheries Society, Manila, Philippines.

Introductions of aquatic organisms into Japan are controlled odly on the basis of the Convention on Intemational Trade in Endangered Species (CiTES) of Wild Fauna and Flora and the quarantine acts. Up to 1986more than 120 exotic species have been introduced, of which only 36 were made prior to 1945. Introductions are classified into four basic categories. In this paper of those in two categories, (i) species which have spread widely over Japan and are self reproducing, and (ii) those which have been maintained for generations through artificial propagation or in confined natural waters are dealt with.

Since the late 19th century, a great number of exotic species of aquatic organisms have been introduced into Japan primarily with a view to enrich the fish resources of the country. While the introduction of some of these species have caused serious ecological problems in naturalwaters, some others have been confined and cultured in aquaculture farms as market fish or well established in natural waters yielding new commodities of food or sports fishing without serious impact on the ecosystem. The evaluation of the transplantation of non-indigenous speciescan vary among people; an exotic fish species in a river or lake may be a acceptable game fish for anglers while it may be an enemy for fishermen who catch other species that are outrivalled by the newcomer. Moreover, we have to admit that the 'ecological sense' of the peoplevary in accordance with the cultural and socio-economic backgrounds of the country, even though conservation is the unanimous consensus of all nations. In any event, accumulation of accurate

63 64 information on the status of fauna and flora is essential to lay down effective ;chemesfor controlling introduction of the species. The purpose of this paper is to give a brief historical review of the introduction of exotic species of aquatic animals in Japan and a brief description of the present status of these species. Species introduced as ornamental aquarium fish are excluded from this report.

Review of Aquatic Species Introduced into Japan

It is virtually impossible to trace all of the numerous aquatic organisms introducedinto Japan over the last 100 years. However, efforts have been expended to collect distributional and ecological data on introduced exotic species by various institutions including theFisheries Agency, prefectural fisheries stations and universities. The EnvironmentAgency's on-going nation-wide survey of the distribution of freshwater fishes, which is carried out every 5 years, has also provided disributional information on the exotic species which have beennaturalized in inland waters (Environmental Agency 1976, 1980, 1988). There has been no regulation to control the introduction of aquatic aninuls from an ecological standpoint. Animals brought in from abroad are checked only on the basis of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), the municipal laws established in relation to the CITES, and the Quarantine Acts. Recently,FAO's program of the prevention of internationalepidemics was put into operation at the Fish Disease Center in Tokyo. According to Maruyama et al. (1987), more than 120 exotic species of aquatic animals have been brought to Japan up to 1986. Of these, only 36 species were introduced to Japanbefore 1945. Entering the postwar period, the number increased drastically, due largely to tile increasing demand for new commodities among commercial fishermen, aquaculturists and Sports fishermen and the development of transportation. Many of these species were introduced intentionally for stocking in the natural environment, commercialculture and/orsportfishing.Somespecies,such asthesilvercarp, Hypophthalmichthys molitrix and the bitterling, Rhodeous ocellatus ocellatus came to Japan accidentally;these two speciesarrived in Japan mixed with fry of the grass carp, Ctenopharyngodon idella (Nakamura 1955). Of the 120 species brought into Japan, about 9 species accounting for 7.5Vc of thetotal number have acclimatized themselvestothenatural environment asself-reproducing populations; about 32 or 26.7% have been successfully bred; about 26 or 24.6% have disappeared; the status of about 53 or 4 1.2% remains obscure. In Table 1 they are classified into four categories; (1) species which have spread widely over Japan and areself-reproducing, (2) species which have been maintained for generations in captivity through spontaneou.s or artificial reproduction and/or established as self-reproducing populations in limited areas of natural waters, (3) species which are already extinct in Japan, and(4) species of which the present status cannot be elucidated. The following description by taxonomic groupdeals with only species which belong to categories 1 and 2 above and which are considered to have aneconomic or ecological importance. 65

Sa!monidae

Examples of successful introduction of species foraquaculture are evident amongst salmonids, particularly the rainbow trout, Salmo gairdneri. Sinceits first introduction in 1877, many strains of rainbow trout have been imported from various localities ofNorth America. This species is now the commonest species in cold-water aquacultureponds in Japan and its annual production is maintained at 15,000-20,000t. Programs of stocking of rainbow trout fingerlings in rivers have also been in operation inmany areas since 1955. However, reproduction of the fish in natural waters has been confirmed only in Hokkaido (Kawanabe1980). Other exotic salmonid species that are knownto reproduce in natural waters are the brown trout, Salmo trutta and the brook trout, Salvelinusfontinalis. A number of species of the salmonidgenus Core gonus have been introduced from East European countries for pond culture; still in experimentalstages at research institutions and private farms. Core gonus species C. lavaretusmaraena and C. peled among others are regarded as promising candidates for cold-water pond culture in Japan.

Cyprinidae

Four species of Chinese carps Ctenopharyngodonidella, Hypophthalmicht/jys molitrix, Aristichthys nobilis and Mylopharyngodon piceusare reported to reproduce in the Tone, one of the largest rivers in Japan (Inaba 1955), Though theyare of no high commercial value, the former two species are of some importance in thecommercial fisheries in the area. Because of their low trophic levels, there have beenno reports indicating disturbances of river fauna because of these species. The bitterling Rhodeous ocellatus ocellatus isa small cyprinid occurring in continental East Asia accidentally introduced into Japan mixedwith grass carp fry from China, andwas first found in Japanese freshwaters in the mid-1940s(Nakamura 1955). Since then it has been expanding its distribution, most remarkably in the last decade,expelling the Japanese subspecies R. ocellatus smithi by ecologicalpressures and hybridization. R. ocellatus smithi isnow on the brink of extinction as a distinct subspecies (Nagataand Nishiyama 1976).

Atherinjdae

The atherinid Odonthestes bonariensis, knownas pejerrey in South America, was introduced into Japan from Argentina in 1966as a species suitable for pond culture and stocking in lakes. It has turned out that the speciescan readily reproduce in captivity and the fish is now cultured at several fisheries stations and private farms.Seed has been stocked repeatedly in Lake Ashinoko and Lake Tsukui to createa new commodity of sport fishing, but it is not evident that the fish has adjusted itself in these lakes (Watase 1986).

Centrarchjdae

The North American bluegill, Lepomis macrochirus andlargemouth bass Microprerus salmoides have readily established themselves in rivers andlakes and are spreading rapidlyover 66

Table 1. List of exotic aquatic species (Status 1 - Established as self reproducing populations;Status 2 - being reproduced in certair. experunental or natural ponds; Status 3 - extinct at present; Status 4 - accurate information not available; UI,unintentional). Remarks Taxonomic Status Introduced Status From Year

Pisces Acipenseridae Acipenser guldenstadti 3 USSR 1963- A.baeri 3 USSR 1964 Huso huso x USSR 1974- Acipenser ruihenus

Clupeidae Alosa .capidissima 3 USA 1928/29

Anguillidae Anguillajaponica Korea 1964- Elver foi commercial culture 7 China 1964- 7 Taiwan 1964 A. anguilla 7 France 1969 7 Italy 7 England A. rostrata 7 Canada 1971(72 A. dieffenbachi and or 3 New Elver for commercial culture A. australis Zealand 1970173 A. bicolor pacfica 3 Philippines 1972

Salmonidae Salmo gairdneri 2 USA 1877 5. trutta 2 USA 7 - 1926 S. salar 7 USSR 1980/83 Oncorynchus tshawytscha 7 USA 1881- O.nerka 7 Canada 1957 ? USA 1968 0. kisutch 2 USA 1965 Sal velinus naniaycush 2 Canada 1966/69 S.fontinalis 2 USA 1901126 Core gonus lavaretu.r maraena 2 Czecho 1977/78 C. 1. ludoga 7 USSR 1981 C. autu,nnalis migralorius ? USSR 1969- C. mukcun USSR 1981/83 C.peled 2 Czecho 1972- USSR 1978- C. clupeaformis 3 USA 1926129 C. olbus 3 USA 1926/29 C. lavaretus baeri 3 USSR 1929/30 C. lavaretus maraena 3 USSR 1929/30

Cyprinidae Tone River S. UI Aristichthys nobilis 2 China 1878- 1940 (mixed in grass carp fry) Tone River. S Cienopharyngodon idellus 2 China 1878- 1955 Tone River. S. Hypophthalmichthys molitrix 2 China 1878- 1940 Tone River. S. UI (mixed in Mylopharyngodon pi ce us 2 China 1878- 1940 grass carp fry) I China 1942- UT; Its Tapanese counter- Rhode us ocellaties ocellatus partR. o. smithiis endangered by ecological pressure of and hybridization with this subspecies.

Continued 67

Table 1. Continued

Taxonomic Status Introduced Remarks Status From Year

Cyprintss carpio ruscis 2 China 1971 Cyprinus carpio 2 Germany 1905- Cross bred 2 Austria 1970 2 Indonesia 1980 Cirrhina rnolitorella 7 China 1965/66 Megalobrama amblycephala 2 China 1978 Tinca tinca 2 Netherlands 1961 Carassius auratus gibellio 3 USSR 1930/64 Catla catla 3 India 1960 Pakistan 1970 Barbus for 3 India 1960 Labeo rohita 3 India 1960 Cirrhina rnrigala 3 India 1960

Ictaluridae Ictalurus punctaf us 2 USA 1971

Poeciliidae Gambussiaaffinis 1 Taiwan 1916

Atherinidae Odontesthes bonariensis 2 Argentine 1966

Percidae Percaflavescens 3 USA 1960

Centrachidae Lepomis macrochirus 1 USA 1960 Micropterus salnwides 1 USA 1925 Predation on native species Morone interrupla 3 USA 1960 Pomoxs nigromaculatus 3 USA 1927136 Roccus saxatilis 3 USA 1927128 1972173

Chichlidae Oreochromisaureus 2 Taiwan 1980 USA 1983 Syria 1984 0. macrochir 3 USA 1964 0. mossarnbicus 2 Thailand 1954- Colonized polluted brackish waters around Okinawa Island. 0. urolepis hornorwn (reported as 2 Israel 1981 Tilapia macrocephala) 0. niloticus 2 Egypt 1962 Sarotherodon melanof heron 3 USA 1960 S.galilaeus 3 USA 1964 Tilapia sparrmanii 2 USA 1959 T. zulu 2 Egypt 1962

Belontiidae Macropodus chinenth 1 Korea 1914

Osphronemidae Osphronemus goramy 7 Thailand 1956

Scienidae Aplodinof us grunniens 3 USA 1960

Continue 68

Table 1. Continued

Taxonomic Status Introduced Remarks Status From Year

Channidae Channa argus 2 Korea 1923/24 Predatior on native species parasites C. maculata 1 Taiwan 1906/19 Parasites Crustacea Astacidae Pacfastacus leniusculus 2 USA 1909/29 Pond Tar kai in Shiga Pref. P. trowbridgii 2 USA 1928/30 Lake Mashu in Hokkaido Proca,mbarus clarkii 1 USA 1930

Parastacidae Cherax tenuimanus 3 Australia 1981-

Nephropsidae HomarusAmericanus 7 USA 1914 1975178

Penaeidae Penaeus chinensis 7 Yellow 1965- Sea

Palaemonidae Macrobrachiu.m rosenbergii 2 Malaysia 1967- Thailand USA (Hawaii)

Mollusca Unionidae Lamprotula (Quadrula) bazini 3 China 1917 Lampsilis luteola 3 USA 1926 Anodonta woodiana 3 Taiwan 1962

Mytiidae Mytilus edulis galloprovincialis 1 7 ca.1926 UI

Ostreidae Ostrea lurida 2 USA 1948 O.eduh.c 2 France 1952 Crassostrea angulata 7 France 1952 C.virginica 7 USA 1968

Haliotidae Haliotis rufescens 2 USA 1966

Ampullaridae Pila leoporavillensis 1 Taiwan 1981 Hybrid; it is unknown x Ampullarium insciarum whether pure strains have have been introduced or not 69 the Japanese main islands. After its first introduction into Lake Ashinoko in 1925 for lure fishing (Akaboshi 1959) and an initial unsuccessful attempt of its transplantation into several other lakes, transplantation of M. salmoides from Lake Ashinoko to other waters was prohibited to prevent possible destruction of local fish fauna by this predaceous species.However, the attraction of this fish as a game for lure fishing has led some indiscreet anglers to secretly transplant it into many lakes. This resulted in its subsequent rapid dispersal over Japan and its predation on many native fish species. The impact of the largemouth bass on indigenous fish fauna appears to vary particularly in relation to the depth of water (Nomura and Furuta 1977). The predation on indigenous fish by largemouth bass has caused serious problems in shallow waters and efforts to eradicate this predator have not been successful (Kikukawa1980). In deep waters such as Lake Ashinoko, largemouth bass coexist with nativefish by habitat segregation.

Cichlidae Nine species of tilapia have been introduced into Japan for the purpose of pond culture utilizing heat from hot springs or cooling-water discharge from power plants or factories. Of these species, Oreochromis niloticus is enjoying a comparatively high reputation as a food fish, with its annual production reaching more than 5,000 t in 1985 (Maruyama 1986). 0. niloticus, 0. mossambicus, Tilapia sparmanii and T. zulu have colonized estuarine waters in the Okinawa Islands (Imai 1980).

Changes in the Japanese Freshwater Fish Fauna

The freshwater fish fauna of Japan has been changing rather conspicuously in recent years. The freshwater fauna is originally rich in southwestern Japan and comparatively poor in northeastern Japan. The recent changes in freshwater fish fauna are characterized primarily by the dispersal of many species endemic or indigenous to southwestern and northeastern Japan. This northeastward dispersal is considered to be attributable largely to the transplantation of a species called "ayu from Lake Biwa in central Honshu. Though this has little to do with the introduction of exotic species, we believe it worthwhile to briefly mention of what is going on in the Japanese freshwater fish fauna. Ayu, Plecoglossus altivelis, a small, annual fish closely related to salmonids is one of the favourite game fish and an inland water delicacy among the Japanese. Young and sub-adult ayu inhabit the middle to upper reaches of clear water rivers and reach maturity as they descend to the lower reaches where they spawn. Larvae migrate to the sea and juvenile ayu ascend rivers after spending the whole winter in the sea. Due to obstructions on the migration route by dams and other structures, fry of ayu are being released into upstream areas all over Japan in large numbers every year. The majority of the fry released are collected from Lake Biwa where a land- locked population of ayu abounds. This stocking activity is certainly a boon to more than 10 million amateur anglers who enjoy ayu fishing. However, it has created aside-effect; colonization of the inland waters of northeastern Japan by species that had been found only in southeastern Japan. It is widely accepted that the dispersal of southwestern elements has caused by incidental transportation of fry of many species mixed in ayu seed collected from Lake Biwa. These immigrants include a few carnivorous cyprinids and the predaceous largemouth bass. 70

From this historical review, it can be seen that the introduction of aquatic species into Japan is closely related to the development of transportation. Before the World War II, shippingwas the only mode of transportation live species from foreign countriesto Japan. It was difficult for private enterprises to introduce live aquatic species from foreign countries because ofshipping costs. Therefore, only the national and/or local governments were able to introduce the aquatic species from other countries for productive increase of animal protein. As thetarget species were selected by the government authority itself, rules governing introduction of aquaticspecies were not thought to be necessary. Entering the postwar period, the development of transportation drastically increased the number of species introduced from other countries; they are not only used in pond culture, but also as ornamental pet fish in aquariums. Critical changes in fauna and flora caused by exotic species have never been observed as a result of unrestricted introduction of aquaticspecies. However, some changes, as mentioned above, have already been reported. Thosere Rhodeus ocellatus smithi being replaced by R. o. ocellatus, colonization of northeastern Japan by native- born species found in southwestern Japan, and the predation of largemouth bassMicropterus salmoides on many native fish species in certain places. These situations should be consideredas a warning alarm for unrestricted introduction of aquatic species and the need for deliberation and care for further introduction of aquatic species in Japan.

References

Akaboshi, T. 1959. Blackbass. Miyazaki-ken Tansui-gyogyos hidojyo,p. 1-71. Environmental Agency. 1976. Dai 1 kai shizen kankyo hozen kisochosa houkokusho (Report of the first nationalsurveys on the natural environment). Shakai-chosa- kenkyusho. Tokyo, Japan. Environmental Agency. 1980. Dai 2 kai shizen kankyo hozen kisochosa houkokusho (Report of the second nationalsurveys on the natural environment). Shakai-chosa- kenkyusho. Tokyo, Japan. Environmental Agency, 1988. Dai 3 kai shizen kankyo hozen kisochosa houkokusho (Report of the third nationalsurveys on the natural environment). Shakai-chosa-kenkyusho. Tokyo, Japan. Imai, S. 1980. Tilapia in°Nihon no Tansuiseibutsu (Freshwater aquatic species in Japan)". Edited by T. Kawai et al., Tokaidaigaku-shuppankai. Tokyo, Japan, p. 124-132. Inaba, D. 1955. Tonegawa niokem sogyo no hanshyoku (Re producti on of the Chinese Carp in the Tone River). Zenkoku-kosh.D--kasen yoshoku kenku-kai-yohou. Kawanabe, H. 1980. Nijimasu (Rainbow Trout) in" Nihon no Tansuiseibutsu (Freshwater aquatic species in Japan)". Edited by T. Kawaiet al., Tokaidaigaku-shuppankai. Tokyo, Japan, p. 44-48. Kikukawa, Y. 1980. Blackbass in"Nihon no Tansuiseibutsu (Freshwater aquatic species in Japan)". Edited by T. Kawai etSi.,Tokaidaigaku- shuppankai. Tokyo, Japan. p. 20-29. Maruyama. T.K., T. Fuji, Kijima and H. Macda. 1987. Gaikokusan shingyoshu no donyu keika. (Introducing process of extic species from foreign countries). Fisheries Agency, Tokyo. Nagata, Y. and K. Nishiyama. 1976. Remarks on the characteristics of the fins of bitterling. Rhodeus ocellatus ocellatus (Knen and R. ocellatus smithi (Regan). Memoirs of the Osaka Kyoikyu University Series ifi 25(1): 17-2 1. Nakamura, M. 1955. Kanto-heiyani shutsugenshita ishyokugo (Some exotic fishes appeared at the Kanto Plains). Nihon-seibuisu-chiri-gakkaiho 16/19: 333-337. Nomura, M. and Y. Furuta. 1977. Gunma-ken niokem koshyo kasen no koudo gyogyou-riyou ni-kansuru chyosha-hokokushyo. Gunma Prefecture, p. 40-43. Watase, S. 1986. Pejerrey in" Shingao no sakan (New aquatic species in Japan)". Seizando. Tokyo, Japan. The Status of Introduced Fish Species in Malaysia

K.J. ANG Faculty of Fisheries and Marine Sciences Universiti Pertanian Malaysia Serdang, Selangor R. GOPINATH Department of Fisheries TKT 8 Wisma Tani, Jin. Mahameru Kuala Lumpur, Malaysia T.E. CHUA International Center for Living Aquatic Resources Management MC P.O. Box 1501 Makati, Metro Manila Philippines

Ang, KJ., R. Gopinath and T.E. Chua. 1989. The Status of introduced fish species in Malaysia,p. 71-82. In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines.

The fate of introduced fish in Malaysia was traced with special reference to their abilities to establish in local conditions. Of the dozen food fish introduced into Malaysia, only Trichogasser pectoral is, Punt ius gonionotus, tilapias and Clarias macrocephalus were able to establish successfully. Other species were able to grow well in local environment but were not able to propagate naturally. Introduced fishes contribute 88% to total freshwater aquaculture production and 72% to total freshwater fish production. Some diseases found with introduced fish are recorded. Existing laws governing importation of exotic species are examined.

The term "exotic" species has been defined as the introduction ofan organism by man from a foreign country outside the native range of that species (Kohier and Stanley 1984; Kohler 1986). The same authors defined "introduced" aquatic species as a plant or animal moved from one place to another by humans (i.e., an individual, group or population of organisms that occurs in a particular locale as a result of human intervention). These two terms have been used loosely. For the purpose of this paper, the term "introduced" is used to include species introduced from foreign countries also. Malaysia is endowed with a tropical climate, productive marine and terrestial ecosystems, and great species diversity. A large number of fish species has been recorded (Scott 1959; Johnson 1961; Chua 1978; Mohsin and Ambak 1983). Many are commercially important and most have been heavily exploited. Many species were introduced to Malaysia in the early 19th century either by Chinese immigrants for sentimental reasons or by fisheries officials trying to provide development of

71 72 what they perceived as economically useful species. Species introductions have never been a major government thrust because of the availability and abundance of indigenous species. The main concerns about the fish introductions are the risks associated with any one or all of the following problems as listed by Welcomme (1986):

-contamination of existing natural communities with foreign species,

- the introduction of disease,

-the direct disruption of the fish community through competition or predation,

the genetic degradation of the host stock,

the degradation of the environment by the introduced species, and

- the disruption of human lifestyles, customs or economic systems.

It is difficult to find a country in Asia whose natural fish communities are notcontaminated by introduced species. The risks of disease transfer, genetic and environmentaldegradation as well as disruption to the natural fish communities can, however, be reduced if notprevented if appropriate precautionary measures are observed. The objectives of this paper are to tracethe fate of introduced fish in Malaysia and to assess their possible ecological orbiological impact.

Fate of Introduced Species Available records show that fish introductions in Malaysia were initiated in theearly 19th century along with the immigration of the southern Chinesewho brought along the techniques of fish farming. Fingerlings of grass carp (Ctenopharyngodon ide/la), bighead carp (Aristichthys nobilis),silver carp (Hypophthalmichthys molitrix) and common carp (Cyprinus carpio) (Welcomme 1981; Mohsin and Ambak 1983) were raised in mud pondsand unused mining poois. The snakeskin gouramy (Trichogaster pectoralis) was introduced either in thelate nineteenth or early twentieth century and established itself in paddy fields, irrigationcanals and freshwater swamps, forming an important fishery. After World War II, a few more species were introduced by the Departmentof Fisheries, private organizations and individuals. Tilapia (Oreochromis mossambicus) wasintroduced in 1944 from Java. This species rapidly established itself in freshwater as well as inbrackish water. In 1979, 0. niloticus was introduced from Thailand and in 1980, red tilapiahybrids were brought in from Taiwan. These two species/varieties are of better qualityfor aquaculture purposes and they are now popularly cultured in freshwater ponds and mining pools.In the 1L950's catfish (Clarias macrocephalus) was introduced and soon became a strongcompetitor with indigenous species (Clarias batrachus). The Javanese carp, Puntius gonionotus, was successfullyintroduced into Malaysia in 1958 (Table 1). The Department of Fisheries also introduced the Indian major carpsin the 1960's, particularly catla (Catla catla), mrigal (Cirrhina mrigala) and rohu (Labeo rohita).Like most Chinese carps, these species do not breed in captivity under localconditions. Their culture is dependent on imported fingerling supply. Etroplus suratensis wasintroduced in 1975 from Sri 73

Lanka into Sarawak and Sabah. The slow growth rate makes it noncompetitive with other fast- growing species for aquaculture. Besides food fishes, recreational fish species were also introduced. The rainbow trout (Salmo gairdneri) was introduced into the mountain streams of Brinchang, Cameron Highlands in 1935 from Scotland; in 1968, Boh Tea Plantation introduced the same species in Tanah Rata, Cameron Highlands, from New Zealand. In both cases, there was no evidence of breeding although the trout grow to about 750 g. Growth of the domestic and international ornamental fish trade in recent years has greatly promoted extensive importation of freshwater and marine species from all parts of the world. A variety of such species can be seen in most retail aquarium shops (Table 2). Some of the small species such as Poecilia reticulatus and Gambusia affinis introduced for controlling the spread of mosquitoes have now established themselves extensively in many organically rich water bodies. Other species introduced as ornamental fish include the Siamese fighting fish (Betta splendens), the sucker catfish (Plecostomus punctatus) and the molly (Molliniesa sp.) have also established themselves in freshwater ponds and pools (Table 2). The angelfish (Pterophylum scalare), and the Oscar (Atronotus occelatus), have been found to breed naturally in ponds (Ang, unpublished data). Despite the large number of exotic species introduced as ornamental fish in Malaysia, only a few have become successfully established in natural water bodies (Johnson 1963).

Performance of Introduced Species

Snakeskin gouramy

The snakeskin gouramy was reported by Soong (1948) to have been first introduced into Malaysia in 1921. According to Green (1926) it was introduced in the late nineteenth century. Both authorities agree that the transfer was first made in the Krian rice-bowl area, northwestern Peninsula Malaysia. Today it is found widely distributed in swamps, rice fields and irrigation canals throughout the country (Mohsin and Ambak 1983). The Krian rice-bowl area at one time supported a very substantial rice-field fishery. based almost exclusively on the snakeskin gouramy (Merican and Soong 1966). Due to the double cropping of rice and the wide use of pesticides, the snakeskin gourami fishery has been drastically reduced (Tan et al. 1973). The total production from ponds was only 107.5t in 1986 (Table 3). It is difficult to gauge the impact this species has had on the environment. Soong (1948) maintained that this species has had no deleterious effect on other rice-field fishes, especially the climbing perch (Anabas testudineus), the snakehead (Channa striata) and catfish (Clarias spp.). However, it is certain that the indigenous Trichogaster trichopterus has been displaced, at least to some extent, since both have similar feeding habits and occupy the same niche in the paddy field ecosystem.

Chinese Major Carps and Common Carp

Chinese major carps (grass carp, bighead carp, silver carp and mud carp) and common carp, were introduced into Malaysia in the early part of the nineteenth century by Chinese migrants. 74

Table 1. Fate of the introduced foodfish in Malaysia.

Species Introduced Established Current Status Remarks FromYear (reference)

OSPHRONEMIDAE Trichogaster Thailand, 1921 Paddy fields, swamps, cultured in paddy Badly hit by double crop- peer oralis (Soong 1948) canals fields; yield of ping of rice and use of pesti- 94-202 kg/ha (Tan cides; infected with hemor- et al. 1973); sell rhagic septicaemis; dis- reproducing placed so some extent, the population native species, T. trichopieru.s CICHLIDAE Oreochromis Java, Indonesia, Ponds, canals, tin Self reproducing This species is rarely mossambicus 1944 (Mohsin & mining pools, streams population in fresh cultures. now Ambak 1983) and brackish water, prolific breeder and stunted growth 0. niloticus Thailand, 1979 ponds, reservoir mono or polycultured Self reproducing in mining pools in ponds and cages; pools reach 400-600 gin 4 months Red tilapia Taiwan 1980, Ponds Cultured in ponds hybrids Thailand 1981, Etroplus Sri Lanka 1975 Ponds introduced in ponds Breeds also in brackish- suratensis (Welcomme 1981) in Sarawak water p)nds CLARI[DAE Clarias Thailand, 1950 Ponds, swamps Cultured in ponds Breed üi natural ,nacrocephalus (Tweedie 1952) and paddy fields habitats CYPRNTDAE Puntius Indonesia, 1958 Rivers, ponds, mining Polycultured in Breed in local waters gonionot 555 (Welcomme 1981) pools pond Ctenopharyngodon China, Early 19th Important pond cultured idella century (Welcomme species. Attained 2-3 kg 198 1) in6months Doesnot breed in pond or captivity. Fry imported from Taiwan or Hongkong. Parasites are Chloromyxurn lageri, Sanguznicola armata, Argsdus (Faizxh 1986) Aristichihys China, early 19th Cultured in ponds and nobilis century (Welcomme mining pools. Does not 1981) breed in captivity. Common parasites are Dictylogyrue, Trichodina, Chilodonella (Shariff and Sommerville 1986; Faizah 1986) Hypophthalmichthys China, early 19th Cultured in ponds molitrix century (Welcomme 1981) Cyprinus carpio China, early 19th Ponds and tin mining Polycultured in ponds; century (Welcomme pools minor species for aqua- 1981) culture Indian major carps Introduced from Ponds Do not breed in Not popular in (Catla catla India in 1960 natural habitats Malaysia Labeo rohita, Cirrhina mrigala)

SALMOMDAE Salmo gairdneri Scotland, 1935 Introduced in stream New Zealand, 1968 and lakes in Cameron Highlands as sport fish. Grow to 750 g. No breed- ing reported. Stocking terminated in 1973 for economic reasons Micropterus Florida, 1984 by Stocked in ponds Reported the salmoides Boh Tea Plantation, used for trout earlier presence of fry in Cameron Highlands ponds but none were found down- stream. CHARACIDAE Colossoma sp. Taiwan, 1984 Ponds Cultured in ponds, Subsequently the Dept. attained fast growth Fisheries banned it because its fry resemble those of piranhas 75

Table 2. Ornamental fishes recorded in Malaysia.

Scientific Name Common Name Origin/Source

Abramites macrocephaliss Headstander Amazon/Singapore Aequiden pukher Blue acara Colombia/Singapore Apistogra.mina ramizeri Butterfly cichlid Venezuela/Local Astronottes ocellatus Oscar Amazon/Local Betta splendens Siamese fighter Thailand/Local Botia nacracanthus Clown bach Indonesia/Thailand Carassius auratiss Goldfish China/Local Cichiasoma meeki Fire mouth Guatamala/Singapore Colisa latia Dwarf gouramy India/Local Danio malabaricus Giant danio Sri Lanka/Singapore Gnat honemus petersi Elephant nose CameroonlSingapore Gy,nnocorymbus ternetzi Black tetra Paraguay/Singapore Hyphessobrycon callistus serpae Serpae tetra Amazon H. innesi Neon tetra Amazonlllongkong H. pulchripinnis Lemon terra South America/Local Singapore/Hongkong Kryptoteriss bicirrhis Glass catfish Local and Thailand Labeo bicolor Red-tail black shark Thailand L. erythrura Red-finned shark Thailand Leptobarbus hovenii River carp Local/Indonesia Thailand Metynnis sp. Silver dollar Amazon/Singapore Puntius oligolepis Checker barb Singapore P. scubert Golden barb China Plecostomus punctatus Sucker catfish Singapore Poecelia reticulata Guppy Venezuela/Brazil Singapore Moiliniesa latipina Sailfin molly Local and Singapore Puntius conchonuis Rosy barb Singapore Pterophylwn eimekei Angelfish Local P. scalare Angelfish Local Scieropagesformosus Dragonfish Local/Indonesia/ Thailand Osleoglossum Syenphysodon spp. Discus Local Trichogaster leeri Pearl gouramy Local, Thailand T. trichoplerus sumatranus Opaline gouramy Xiphophorus helleri Swordtail Local/Singapore X. ,waculatsss Platy Singapore

Note: The term source is used here where fish were obtained. It does not denote local occurrences.

Table 3. Production of introduced fish species in ponds at Peninsular Malaysia in 1986. (Soutce: Annual Fisheries Statistics, 1986).

Common Name Species Production (t)

Javanese carp Puntius gonionotus 968.6 Common carp Cyprinus carpio 259.3 Grass carp Ctenopharyngodon idella 1,516.4 Bighead carp Aristichthys nobilis 734.5 Tilapia Oreochromis spp. 571.7 Snakeskin gourami Trichogasterpectoralts 107.5

TOTAL 4,158.0

Total freshwater production (ponds & wild) 5,753

Total freshwater fish production by aquaculture 4,709 76

While it is likely that at the onset, all these species were cultured (Birtwhistle 1931), local market preferences gravitated towards grass carp, bighead carp and common carp. Silver carp and mud carp have little commercial value and are not popularly cultured. None of the Chinese major carps breed naturally in captivity and have neve] established themselves in local waters. Public stocking programs involving grass carp were first carried out in the Bukit Merah and Cenderoh impoundments in the early 1960's. Though sporadic reports of adults of 11 kg being caught were reported, results on the whole were not encouraging (FAO 1965). Bighead carp fingerlings were stocked in the Durian Tunggal, Paya Nakoh and Ampang reservoirs. The absence of catch data prevents meaningful assessments of the introduction. On the whole, the release of common carp fry into public waters has been avoided because of their scouring habits which weaken bunds and increase water turbidity. Common c arp has not established itself to any major extent. The Chinese carps constitute the mainstay of Malaysia's freshwater aquaculture industry. In 1986, grass carp, bighead carp and common carp contributed 53.3% by weight and 48.7% by value of Peninsular Malaysia's freshwater aquaculture harvest (Table 3; Annual Fisheries Statistics 1986).

Rainbow Trout

Rainbow trout (Salmo gairdneri) was first introduced in Brinchang, Cameron Highlands in 1935. Eyed ova, imported from Scotland, were hatched in a now-abandoned facility and the fingerlings released in the Tenom River. No details are available on the numbers released, nor how they fared in the new ecosystem. However, there were unconfirmed reports from villagers living in the area that berried females weighing about 750 g could be caught from the same river (Somasekheran, pers. comm.). The program ceased during World War II. In 1968, Boh Plantations Limited, a tea company in Tanah Rata (also in Cameron Highlands), began a trGut project for recreational purposes. Fingerlings were released in three lakes, each of about 3 ha. However, no reliable records on numbers released and. catch were made. Mature females were frequently caught, but there was no evidence that the fish bred in local waters. Indeed, maintenance of fish stocks necessitated regular releases of trout fingerlings. The project was terminated in 1973 mainly for economic reasons. Significantly, disease problems (whirling disease) in the hatchery were a major impediment to the continuation of the project.

Tilapia

Tilapia, Oreochromis mossambicus, was first introduced into Malaysian waters from Java by the Japanese during World War II. O.mossambicus rapidly established itself, particularly in mining pools, impoundments, and even some coastal areas such as the Johore Straits, bordering Singapore and Malaysia. 0. mossambicus was initially well received by farmers. In the 1950's it was actively cultured in ponds and mining pools throughout the country. However, its frequency of reproduction meant that adults did not grow beyond 200 g. While fish production per unit area was high they consisted of stunted individuals with little marketability. The fish was also difficult to eradicate from ponds, particularly undrained ponds and competed with preferred 77 species for food and space, again leading to poor growth, this time among other species of fish. By the early 1960's, tilapia began to be regarded as a nuisance. In a bid to overcome problems inherent in 0. mossambicus culture, attempts were made to develop all-male hybrids. Hickling (1960) experimented on hybridization and as a result of his experiments Oreochromis niloticus, 0. hornorum, Tilapia zulu and T. rendalli were introduced into Malaysia. He was successful in obtaining an all-male hybrid (0. mossambicus x 0. hornorum), but it did not find lasting commercial success in Malaysia. This is because hybrids were contaminated by stray 0. mossambicus. In 1972, the Department of Fisheries officially ceased all production of 0. mossambicus in its hatcheries. A policy of discouraging its culture was also instituted. The policy was revised only in 1975, with the recognition of 0. niloticus as an acceptable alternative. While 0. niloticus was originally brought into Malaysia in the 1960's, pure lines were not maintained. Therefore, in 1979 a stock of pure 0. niloticus consisting of 400 individuals was imported from Chengmai, Thailand, and raised in the Department of Fisheries hatchery of Jitra, Kedah. This stock constituted the broodstock for all the Department hatcheries to the present. The Department of Fisheries first imported six red tilapia from Thailand in 1981. A second importation consisting of 500 individuals was made from Thailand in the same year. In 1982, a stock of red hybrids was imported from Taiwan and maintained in the Freshwater Fisheries Center, Bukit Tinggi, to prevent interbreeding with wild stock or with each other. Red tilapia found a lucrative urban market, and before long commercial culture of red tilapia started. However, soon demand outstripped production by 12.7% in 1983, 22.5% in 1984, 24.7% in 1985 and 19.6% in 1986. The industry was also very substantially different from the one that raised 0. mossambicus thirty years earlier. Tilapia was then raised by small farmers in ponds and mining pools using semi-intensive and extensive methods. The red tilapia, while still relying substantially on such methods, saw the proliferation of commercial, intensively operated farms using formulated feeds and high rates of water exchange. Markets have also changed. Where 0. mossambicus was sold fresh at the wet markets, red tilapia is consigned mainly to the restaurant trade which demands live fish. Live red tilapia is also sold in specific supermarkets under the name red snapper or cherry snapper. There is little documented evidence of impact of the tilapia in Malaysian waters. The proliferation of 0. mossambicus particularly in mining pools and lakes, is generally recognized as having affected local icthyofaunal populations but the species affected and extent to which they have been affected is not documented. The massive importation of red tilapia fry may have brought in non-indigenous epizootics. A lack of suitable baseline information on the fish disease status of the country however, prevents any meaningful comparisons. Red tilapia (particularly those not treated for monosexuality) are no less prolific than 0. mossambicus. It is no longer uncommon to see mining pools filled with red tilapia fry and stunted red fish. These fry have undoubtedly escaped into rivers and streams, where they proliferate, breeding either with themselves or with wild 0. mossambicus stock. At this point in time, red tilapia have yet to match the widespread distribution of 0. mossambicus. Whether they will or not is an open question and will depend on their hardiness and their capability to compete with resident animals. 78

Pearl Spot

The pearl spot, Etroplus suratensis, which is a brackishwater cichlid found in India and Sri Lanka (Ong 1983) was introduced to Sarawak, Malaysia from Sri Lanka in 1975 (Welcomme 1981). The species breeds readily in freshwater or brackishwater, in ponds. They, however, are not found in large quantities in natural bodies of water.

Catfishes

The catfish Clarias macrocephalus was introduced in 1950 from Thailand (Tweedie, 1952) and has been able to propagate in swampy ditches and is also found in paddy fields and pools. It can be cultured in ponds. Although they can breed naturally in swampy areas, they have not been able to compete with the indigenous catfish, Clarias batrachus.

Javanese Carp

The Javanese carp, Puntius gonionotus, locally called Lampam Java, was first Fitroduced in 1953 (Welcomme 1981). Stock obtained from Indonesia was raised in the Tahpah Fish Breeding Center in Perak (Somasekheran, pers. comm.). In the late 1960's further introductions of P. gonionotus stock, this time from Thailand, were made. The fish was bred with existing broodstock and the progeny were distributed among the Department's five breeding stations. The last importation of P. gonionotus stock was from Indonesia (Soong 1963). Javanese carp is one of the most popular cultured fish in Malaysia. In 1986, some 969 t of fish were raised by fish farmers amounting to a total wholesale value of M$ :2.76 Million, ranking second after the Chinese major carps in the freshwater aquaculture industry (Table 3). However, while Chinese major carps are raised by commercial fish farmers, the Javanese carp is highly preferred by subsistence farmers. It is also the primary species involved in the Department of Fisheries open-water stocking program since the 1960's. The importance of the Javanese carp is underscored by the production figures of Government freshwater breeding centers. The release of Javanese carp in public waters over the last 20 years has established this species as part of the Malaysian icthyofauna. The fish is caught by subsistence fishermen mainly to supplement domestic requirements. There is however, no commercial fishery. As with other fish, it is very difficult to evaluate the environmental impact of the Javanese carp. There is no evidence that the Javanese carp has displaced any indigenous puntid species.

Indian Major Carps

The Indian major carps, i.e., catla, rohu and mrigal were imported from Calcutta in 1960 and raised in the Tapah Fish Breeding Station (Welcomme, 1981). Part of this stock was removed to the Freshwater Fisheries.Research Station at Malacca. The culture of the Indian major carps has not proved popular. However, rohu is still cultured in the states of Negeri Sembilan and Malacca to a limited extent. Rohu fry are also produced on an ad hoc basis by the Freshwa:er Fisheries Research Station in Malacca and are consigned entirely to the open water stocking program. 79

The Indian major carps, in common with Chinese major carps, do not breed naturally under local conditions. That, coupled with the fact that distribution of fry has been limited, has meant that these carps have not had any significant biological or ecological impacts on the local fish fauna.

Pacu

The Pacu (Colossoma sp.) was introduced to Malaysia about 1984. It was the first South American fish to be cultured locally. The main focus of this culture activity was the Ulu Kelang area. However, the Department of Fisheries subsequently banned the fish because its fry could not be distinguished from the piranha, Serrasalmus and Rooseveltiella.

Black Bass

Micropterus salmoides represents the latest introduction in Malaysian waters. The fish was imported by Boh Plantations Ltd. in 1984 as an attempt to revive their recreational program. About 1,000 fry were imported from Florida and raised in the Boh hatchery to fingerling size before being released in two lakes each about 3 ha in size. The lakes were the same water bodies that accommodated trout 10 years previously. Angling was permitted after one year. Mature adults weighing about 300-350 g were caught. However, there has been no reports of the same fish downstream of the lakes, and one can assume that bass is so far restricted to the lakes.

Problems of Disease and Parasites from Introduced Species The problem of introducing diseases into the local fish fauna can be a serious one. Such introductions may come through the importation of food fishes and ornamental fishes into the country. At the moment there are no procedures to examine and ensure that all imported live fish are free from disease. Shariff and Vijiarungam (1986) and Shariff and Sommerville (1986) have reported the occurrence of parasites in the freshwater fishes of Malaysia. Their findings are summarized in Table 4. Shariff and Sommerville (1986) remarked that the free flow of infected fish from the breeding stations and theimporting agency resulted in the spread of Lernaea in Peninsular Malaysia. Shariff (1980) also indicated that Lernaea was brought into the country probably through exotic ornamental fish.

Existing Policies and Regulations on Introduction of Exotic Species into Malaysia

While State enactment has existed from colonial times (F.M.S. Enactment No. 20 of 1937; Kedah Enactment No. 40; Kelantan Enactment No. 32 of 1939; Perlis Enactment of 1334; 80

Trengganu Enactment No. 8 of 1963; Sarawak Ordinance Cap. 73), thefirsi:Federally constituted statute covering the fisheries sector came only with the Fisheries Act 1963. Under Section 21(K), the Act empowers the Minister of Agriculture to "prohibit or control the importation into, or the sale, cultivation or keeping in West Malaysia of live fish or any particular species of fish which are not natives of West Malaysia and in Sabah andL Sarawak of live fish or any particular species of fish which are not natives of Sabah and Sarawak'. In 1973, the Minister announced the prohibition of import of Piranhas (Serrasa!mus sp.) in the states of West Malaysia and East Malaysia except with the written permission of the Minister. This regulation was extended to cover piranhas of all genera including pacu whose adult or fry resemble the dangerous Serrasalmus or Rooseveltiella. In 1984, a new Act, the Fisheries Act 1984, was passed to replace the aging earlier act. The new act is more embracing than the earlier act. Under Section 40(1), "anybody who imports into or exports out of Malaysia or transports live fish from West Malaysia to Labuan or Sabah and Sarawak, or transports from Labraun or Sabah and Sarawak to West Malaysia without a permit or violates any condition on a permit issued by the Director-General of Fisheries under this Act is guilty of an offence." Section 40(2) in the same Act reads as follows:- "The Director-General may lay down any condition that is considered necessary on the permit, including conditions pertaining to the sanitation of the fish that is to bexported, imported or transported and measures to avoid the spread of communicable disease or to avoid or to control release of non-indigenous fish in the environment." In 1987, Malaysia ratified its inclusion in the Convention of International Trade in Endangered Species (CITES), a move that automatically stopped all imports of species listed in IUCN's Red Book. Most affected by this was the aquarium fish trade, in particular the importation of Scieropages formoses, a popular aquarium species which is imported from Thailand and Indonesia to meet the local demand. Trade in other fish, particular:[y the South American equivalent of Scieropages, the arawana (Osteoglossum bicirrhosum), was also affected. The Government is also committed to setting up a comprehensive quarantine network to control the entry of exotic epizootics. Section 40(2) of the Fisheries Act 1984 was, in fact, framed with such a view in mind. Quarantine centers will be set up over the next five years in five major entry points. These centers will mitigate to some extent any negative impact of introductions, besides serving to enforce import regulations of these species.

Conclusions

The dearth of literature makes it very difficult to accurately assess the biological impact of food fish species introduced into Malaysia in the past seven decades and the large number of exotic ornamental species imported very recently. However, information available indicates that the introduction of Chinese carps, Indian major carps, rainbow trout and black bass have very little visible ecological impact on the freshwater ecosystem. This is partly because of their inability to reproduce in natural water bodies. However, a few species such as Trichogaster pectoralis, tilapias, Puntius gonionotus and C/arias macrocep ha/us have successfully established in Malaysian freshwater habitats. There is no negative impact of introduced species on human life-styles, customs or economic systems. In fact, some introduced food fishes such as Chinese carps and the snakeskin 81 gouramy have positive economic impacts as wellasnutritional contribution to rural communities. Similarly, the ornamental fish trade has grown considerably from US$ 100,000 in 1973 to the current value of US$ 4 million (New Straits Times, 21st January 1988). There is still potential to increase the ornamental fish trade to US$ 32 million of the US$ 4 billion world wide trade (Ang, unpublished data). Present economic benefits derived from ornamental fish trade and introduced food fish should not be used to justify indiscriminate introduction without considering the risks associated with introductions. Every effort should be made to reduce the risks by appropriate quarantine procedures. Malaysia's inclusion in the convention of International Trade on Endangered Species (CITES) is a useful step in this direction. The revised Fisheries Act and Government efforts to establish quarantine stations to monitor imported species are welcome moves.

Table 4. List of parasites and their hosts at the freshwater breeding stations in peninsular Malaysia.

Station Host Parasites

Enggor Cyprinus carpio Monogenetic trematode, Lernaea cyprinacea Piscinoodiniu,n sp., Trichodina sp. Trichogaster pectoralis Trichodina sp. Tilapia sp. Monogenetic trematode Puntius gonionotus Trichodina sp., Piscinoodiniwn sp. Tanah Rata Cyprinus carpio Monogenetic trematode, Trichodina sp., Myxobolus sp., Lernaea cyprinacea, Argulus japonicus Machang Cyprinu.s carpio Monogenetic trematode Trichodina, Lernaea cyprinacea Ctenopharyngodon idella Trichodina sp., Monogenetic trematode Puntius gonionotus Lernaea cyprinacea Bukit Tinggi Aristichihys nobilis Lernaea cyprinacea, Lernaea piscinae, Monogenetic trematode Puntius gonionotsLs Lernaea cyprinacea, Trichodina sp.,idhyopht hirius mu11fihiis., Piscinoodium sp. Cypriniu.s carpio Monogenetic trematodes Tapah Puntius gonionotlis Trichodina sp., icthyophthiriu.s mutt iJiliis, Lernaea cyprinacea, Monogenetic trematode, Piscinoodium sp. Cyprinus carpio icthyophlhiriu.s mutt fihiis, Argu!usjaponicus, Piscinoodiu,n sp. Hetostoma temmincki Monogenetic trematode, Lernaea cyprinacea Jitra Cyprinus carpio Lernaea cyprinacea, Trichodi,za sp. Tilapia sp. Monogenetic trematode, Piscinbodiu,n sp. Tilapia sp. Trichonida sp., icthyophthirius nzuttiflhiis Puntius goni000tus Lernaea cyprinacea, Monogenetic trematode Kong Kong Cyprinus carpio Lernaea cyprinacea, Monogenetic trematode 82

References

Annual Fisheries Statistics. 1984-1986. Department of Fisheries, Malaysia. Birtwhistle, W. 1931. Rearing of carps in ponds. Malayan Agricultural Journal 19(8): 372-383. Chua, C.W. 1978. Commercial prawns of Peninsular Malaysia. Ministry of Agriculture, Kuala Lumpur, 48 p. Faizah Mohd, Shaharom. 1986. The parasites of bighead carp (Aristichthys nobilis) and grass carp (CIe,wpharyngodon idella) from Peninsular Malaysia, p. 226. In MJ. Howell (ed.) Handbook of Sixth International Congress of Parasitology. Australian Academy of Science. FAMA. 1987. Harga barangan pertanian Tahunan. Federal Agricultural Marketing Authority, Kuala Lumpur. (unpublished data). FAQ. 1965. Report to Government of Malaysia. Development of inland fisheries with special emphasis on fish culture. FAO Prcject MALITEIF1. Report No. 2095. Green, CF. 1926. Fish Culture. Annual Report of the Fisheries Department. SS & F.M.S. Hickling, C.F. 1960. The Malacca tilapia hybrids. Journal of Genetics 37(1). Johnson, D.S. 1961. Freshwater life in Malaya and its conservation. Malayan National Journal, Special Issue, 232-239. Johnson, D.S. 1963. The fate of introduced fish in Malaya. Proc. XVI International Conference of Zoology, Washington, I).C. August 20-27, 1963. p. 246. Kohler, L.C. 1986. Strategies for reducing risks from introduction of aquatic organisms. Fisheries 11(2): 2-3. Kohler, L.C. and J.G. Stanley. 1984. A suggested protocol for evaluating proposed exotic fish introductions in the United States, p. 387-406. In W.R. Courtenay and JR. Stauffer (eds.). Distribution, Biology and Management of Exotic Fishes. The John Hopkins University Press, Baltimore, MD. Merican, A.B.O. and M.K. Soong. 1966. The present status of freshwater fish culture in Malaysia. Paper presented at FAQ World Symposium on Warm-water Pond Fish Culture, Rome, Italy, 18-25 May 1966. 12 p. Mohsin, A.K.M. and M.A. Ambak. 1983. Freshwater fishes of Peninsular Malaysia. Universiti Pertanian Malaysia Press, Kuala .umpur. 284 p. New Straits Times. 1988. Fishing for business. N.S.T. Times Two. 21st Jan. 1988. Ong, KS. 1983. Aquaculture developmentinMalaysia in the 80's. Risalah Perilcanan No. 18. Dept. of Fisheries, Malaysia. Scott, J.S. 1959. An introduction to sea fishes of Malaya. Government Printer (Fudge), Kuala Lumpur: xii + 1-180. Shariff, M. 1980. Occurrence and treatment of ectoparasitic disease of aquarium fishes in Malaysia. Malayan Veterinary Journal 7: 48-59. Shariff, M. 1984. Occurrence of Chilodonella hexasticha (Klemik 1909) (Protozoa, Ciliata) on bighead carp Aristichihys nobi1s (Richardson) in Malaysia. Tropical Biomedicine I: 69-75. Shariff, M. and C. Somerville. 1986. Identification and distribution of Lernaea spp. in Peninsular Malaysia, p. 269-272. In J.L. Maclean, L.B. Dizon and L.V. Hosillos (eds.) The First Asian Fisheries Forum. Asian Fisheries Society, Manila, Phillipines. Soong, M.K. 1948. Fishes of the Malayan paddy fields: 1. Sepat Siam. Malayan National Journal 3(2): 87-89. Soong, M.K., 1963. A note on the pond culture of Puntiiesjavanicus (Bikr) in the Federation of Malaya. Proceedings IPFC 10(2;: 170-173. Tan, C.E., B.J. Chong, H.K. Sier and T. Moulton. 1973. A report on paddy and paddy field fish production in Krian District, Perak. Ministry of Agriculture & Fisheries Bulletin No. 128: 58 p. Tweedie, M.W.F. 1952. Notes on Malayan freshwater fishes. Bulletin Raffles Museum 24: 63-95. Welcornme, R.L. 1981. Register of international transfers of inland fish species. FAQ Fisheries Technical Paper. (213): 120. Welcornme, R.L. 1986. International measures for the control of introductions of aquatic organisms. Fisheries 11(2): 4-9. The Introduction of Exotic Aquatic Species in the Philippines

ROGELIO 0. JULIANO Univesizy of the Philippines in the Visayas Iloilo City, Philippines RAFAEL GUERRERO Ill Philippine Councilfor Aquatic and Marine Research and Development College, Laguna, Philippines INOCENCIO RONQUILLO Bureau of Fisheries and Aquatic Resources Quezon Blvd., Quezon City, Philippines

Juliano, R.O., R. Guerrero ifi and I. Ronquillo. 1989. The introduction of exotic aquatic species in the Philippines, p. 83- 90. In S.S. Dc Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Publ. 3, 154 p. Asian Fisheries Society, Manila, Philippines.

Philippines is an archipelago with a number of islands, each with its characteristic flora and fauna. Aquatic organisms have been introduced into the Philippines mainly for increasing production, as a protein source for the poor. Not all the introductions, however, have been successful. Some of the introductions have had detrimental effects on the endemic fish fauna, particularly the cyprinid flock of Lake Lanao. Recommendations for possible future introductions are suggested.

Aquatic species found in inland waters particulary in outlying lakes and rivers may remain isolated for a long period of time without interference from man. In an archipelago like the Philippines with numerous islands, the isolation of such aquatic species and even land species still occurs. Over the years, through man's interference, such isolation has been broken through introduction of new species, which may completely dominate and wipe out the endemic and/or indigenous aquatic species. Lake Lanao in the island of Mindanao has many endemic cyprinids and their taxonomy and genetics had aroused much interests. The stocking program of the Government with the view to increasing production from lakes accidentally introduced a freshwater, carnivorous goby (Glossogobius giuris) into Lake Lanao. The goby is now a predominant species in the lake and has been responsible for depleting the cyprinid populations in the lake. Herre (1924) states, "In the Philippines, Cyprinidae are apparently confined to Mindanao, Basilan and Tawi-Tawi, and to the Palawan biological province, where they occur on Balabac, Palawan, Busuanga and Mindoro". Herre continues to say that the Cyprinidae of Mindanao entered from Borneo over a Sulu Land bridge. The cyprinids of lake Lanao have been isolated a

83 84 long time ago as shown by the fact that three genera and all of the species of cyprinids living there are endemic to the Lake. Introduction of exotic species into the different islands from other islands of the country or from other countries, requires serious study and careful consideration, particulary on adverse effects such introductions may produce on endemic and indigenous species. Government should adopt strict policies and guidelines to regulate introduction of exotic species. Almost all aquatic introductions into the country were meant to benefit the country, through aquaculture, capture fisheries, or for biological control purposes. However, the benefits that were derived did not really outweigh the adverse effects that came about as a result of some of the introductions. There were introductions of exotic aquatic species that were done by individua:ls without the knowledge of the Government. Even in pet shops in Manila, exotic species of fishes can be found which were brought into the country without government clearence. Certain species that are or were available for purchase from pet shops or dubious sources arespecies of Serrasalmus (pirranha), Pangasius and other catfishes. Such exotic species fortunately are not yet found in the wild and are evidently confined as pets for the time being. No action on the part of the Government has been observed to regulate such introduction.

Recorded Exotic Fish Species in the Philippines

The first recorded introduction of an exotic fish species to the Philippines was in 1907 when Mr. Alvin Seale was authorized by the Philippine Insular Government to import from California, fingerlings of largemouth bass, Micropterus salmoides. Introductions as a food fish and for sport, were made in ponds and lakes specially in higher altitudes in the MountainProvince (Baguio City) and Caliraya Lake in Laguna Province. This species does very well in higher altitudes where temperatures are the same as subtropical zones. Luckily, this fish did not thrive in lowlands where many lakes abound. It is only in Lake Caliraya that M. salmoides is known to be doing well, at 700 meters above sea level, and in 1985 another related species, Micropterus salmoides floridanus was received as a gift from California and stocked in Caliraya Lake (a reservoir). Bass fishing tournaments are held in this reservoir regularly. Subsequently, other introductions of aquatic species, mostly fish, were made with reasons that varied from providing more food fish for the country in lakes and rivers, for aquaculture purposes, for biological control of undesirable species such as mosquitoes and weeds, for sport fishing and others. Some of the introductions became nightmares for aquatic-based industries like the brackishwater farming industry; for e.g., introduction of Mollienesia latipinna (molly) for the purpose of controlling malarial mosquitoes. The mosquito fish, however, became a pest in brackishwater ponds. Other fish species introduced for control of mosquitoes were Gambusia affinis, Poecilia reticulata and Fundulus heteroclitus. The introduction of Tilapia mossambica (Mossambique tilapia) was a real nightmare for brackishwater farming, competing for food in the farm with Chanos chanos (milkfish). The Mossambique tilapia is now an established species in brackishwater farms in the entire country. The Philippine freshwater catfish, Clarias macrocep ha/us, became completely dominated by an exotic species, C/arias batrachus, imported from Thailand during the craze forcatfish farming patterned after the success in Thailand. Clarias batrachus now dominates natural populations in lakes and rivers and the indigenous C. macrocephalus can hardly be found in the markets nowadays. C. macrocephius has better qualities as a food fish compared to C. batrachus. 85

Other introductions did not make much impact and these were not regarded by Filipinosas significant in terms of benefits and adverse effects. The introduction of Ictaluruscatus, Ictalurus punctatus, Lepomis macrochirus, Misgurnus auguillicaudatus (bach), Puntius javanicus, Osphronemus gorami and others for a time created some interest but did not affect the environment as much as other introductions. The Ictalurus species did not survive in natural conditions in the Philippines and no natural population is known. Lepomis (bluegill) is believed to have survived in some reservoirs at high elevations and serves as forage fish for the M. salmoides. The Japanese bach (Mis gurnus anguillicaudatus) established itself insome waters in Trinidad Valley and rice terraces in Bontoc Province but has not had any negative effect. Puntius (tawes) and Osphronemus (giant gouramy) for a while became known as good aquaculture species but eventually lost out to other more favorable and acceptable species for freshwater famiing. The introductions of other cyprinid species in the Philippines and tilapia species have made more impact economically for the Philippines than the other exotics. All available commercial species of cyprinids in the country except in Lake Lanao are considered exotic species. Even the presence of the varieties of goldfishes and carps for aquaria are exotic species but records of their introduction do not exist. The aquarium fish industry benefits from these species. Cyprinus carpio (common carp), and Chinese and Indian carps (such as grasscarp, silver carp, bighead carp, rohu, catla, mud carp, and mrigal) have been introduced into the Philippines. Several Chinese carps and rohu have become a part of natural populations of lakes and reservoirs and contribute to natural fish production. Many have become important cultured species suchas the common carp, bighead, silver carp and grass carp particularly forpen culture in Laguna de Bay and freshwater ponds. Since they can be artificially bred, their domestication has helped the freshwater aquaculture industry. Oreochromis niloticus is now an important freshwater fish cultured in pens, cages and ponds. Among the exotic anabantids in the Philippines, Trichogater pectoralis and T. trichopterus have thrived well in lakes. They have been accepted by consumers inland where marine species hardly influence their preference for fish.

Other Exotic Aquatic Species in the Philippines

Nonpiscine aquatic introductions are not weil recorded but mention will be made of them. In the recent past Ampularia gigas (golden miracle snail) generated interest asa cultured species that can thrive in tanks and even small containers when fed with vegetable materials. They breed in the culture containers and grow at a fast rate. Its success was temporary andmany now consider it as a pest in rice paddies because they feed on young rice plants. Cristaria plicata, a big freshwater clam, all of a sudden appeared as a natural population in the 1970s in Laguna de Bay. It is claimed that the clam may have been accidentally introduced into the lake as glochidia in the gills of imported Chinese carps stocked in the lake. Crassostrea gigas is believed to have been introduced in Pangasinan by Mr. Ablan from Japan. Its culture was studied but without much success. Penaeid shrimps were also introduced into the Philippines (Iloilo) for aquaculture. It is claimed that two species, Penaeus stylirostris and P. vanamei from Latin America when introduced to the Philippines, may also have introduced diseases to local penaeid species. Table 1 summarizes the exotic aquatic species in the Philippines. The data may not be complete as some of the old records are hard to trace. 86

Discussion and Recommendations

Experiences in the past have revealed that many aquatic species have been introduced into the Philippines from other countries either through government efforts or through efforts of private individuals, with or without the concurrence of the Government. Such introductions of exotic aquatic species, mostly fishes and invertebrates, proved beneficial to food production efforts of the Government but in some instances resulted in adverse environmental impacts; the introduced species becoming pests to other crops, new diseases being introduced, with exotic species, and indigenous species being completely dominated or displaced. It also seems apparent from the past that the Government has failed to control and study the negative effects that such introductions would entail, with accidental releases in natural waters taking place. Fortunately, epidemics caused by parasites and diseases accompanying introductions have not yet taken place. Despite many undesirable turns of events from exotic aquatic introductions, adoption of strict government policies on importation of exotic species has been paid only lip service during meetings and workshops. In view of the above, it is recommended that the Government adopts and implements policies, or even enact laws, that will strictly prevent the ill effects of introduction of exotic species into the country. Priority consideration should be given to indigenous and endemic species for utilization to increase fish production in natural waters and in aquaculture before considering exotic species for such purposes. It is proposed that the following be considered as guidelines in the importation of exotic aquatic species into the country: A thorough study of utilizing indigenous/endemic species be made Ibr whatever purposes/objectives have been planned before any decision to introduce an exotic species is made.

If and when a decision to import an exotic species is made, a thorough study of its biology, results of introduction in other countries, and the effects of such introduction on local species and the environment should be undertaken before actual importation is made.

ImportatiOn of the exotic species from a very reliable source, preferably from a research organization where diseases have been controlled and the genetic constitution of the species is guaranteed, should be ensured.

On arrival of the imported species, strict quarantine measures should be undertaken.

It is desirable that no organisms are released into natural waters or to private individuals until the F1 generation or F2 generation has been produced, and which has been given a clean bill of health by pathologists.

Introduction of exotic species in natural waters should be properly monitored and done gradually in one or two areas before any introductions into major natural waters are made. 87

Relevant Literature

Gracia, D.M. 1976. Some notes on the stocking of Cyprinu.s carpia and genguno buna in Pampanga river system. BFAR, Quezon City, 4p. (handout). Herre, A.W.C.T. 1924. Distribution of the tme freshwater fishes in the Philippines. I. The Philippine Cyprinidae. Philippine Journal of Science 24(3): 249-307. Herre, A.W.C.T. 1929. An American cyprinidont in Philippine salt ponds. Philippine Journal of Science 38(1): 121-127. Herre, A.W.C.T. 1931. Checklist of Philippine Fishes, p. 126. Fishes 1931 Philippine Expedition,p. 22, 1934. Rabana, H.R. and L.V. flosillos. 1958. Control of less describe exotic species of fish competing with or harmful to desirable indigenous speciesin inland waters in the Philippines. Philippine Journal of Fisheries 6(1): 49-70. Ronquillo, l.A. 1965. The tilapia and its introduction of new species into freshwater areas. Proc. MAB Inter-Agency Meeting. Seale, A. 1915. The successful transference of blackbass to the Philippine Islands, with notes on the transporting of live fish long distances. Philippine Journal of Science 5(3): 153-160. Seale, A. 1917. The mosquito fish, Gambusia affinis (Baird and Girard), in the Philippine Islands. Philippine Journal of Science 7 (3): 177-187. Velasquez, C. 1975. Digenetic trematodes of Phiippme fishes. Nat. Res. Council Phil., University of the Philippines Press, 140p. Villaluz, D.K. 1953. Fish farming in the Philippines. Bookman, Inc., Manila, 336 p. Table 1. Exotic aquatic species introduced into the Philippines. Present Status Diseases/Parasites production,population,naturallyCommercial breeding masscultured fishesy seed Dacty1ogyrusEdwardsiellaPseudomonasfluorescensA.Aeramonas hydrophila salmonicida, larda Artificially spawned -do-

-do-

Gyrodactyluspopulation,Naturally breeding cultured -do- DactylogyrusMonogenetic trematodes Parasitic, protozoan Trichodina

Naturally breeding population Ichihyophihirius Pisces Taxonomic status From Introduced Year Habitat Oodonium Family CYPRNTDAE Transversotrema larvei skin (under scales) Cyprinus carpio(common carp) China,Hongkong canton 1915 Lakes, reservoirs Commercial fishery nts,I,,os'," -do- Formosa 19261925 pondsrivers,ricefields Lpistyies, (Majalaya(Red(Punten(Sinjonja variety) variety) variety) Strain) IndonesiaBogor,Indonesia -do- 198819571956 HypophthalinichzhysArislichthysC:enopharyngcidon nobilis(bigheadidella (grass carp) carp) TaiwanIndia 19681967 Lakes,Rivers ponds Trichodina LabeoCarassiusCoda rohila coda (rohu)carassius (catla)(cnlcianmoltrix (silver carp) carp) JapanIndia 19641967 PondsLakes, reservoirs Continued Cirrhinus ,nolitorella(mud carp) or PuntiusjavanicusCirrhinusOsteochilus rnrigalaCuvierBleeker hasselti & (Tawes) Valenciennes Bogor,India Indonesia -do- 196719571956 Lakes, rivers Family CICHLIDAE(nilem) OreochromisMozambique(Peters mossambicus (tilapia) tilapia Thailand 1950 Lakes reservoirs rivers, ricefield ponds, swamps 0. niloticu.saureus(Blue(Nile tilapia)mouthbrooder) Alabama,IsraelThailand USA 197719731970,1972 highlands -do- Table 1. ContinuedTaxoornic status Introduced Habitat Present Status FamilyTilapia zuluOSPHRONEMIDAE(Zill's tilapia) IsraelFrom 1977(?)Year Reservoirs, lakes Trichogasserplasalid)Hene pectoral (snake-skin is ThailandBangkok, 1938 pondsLakes, ricefields Naturally breeding T. trichopserusHerre (Three spot -do- 1938 Lakes, rivers Naturallypopulation, breding cultured plasalid) ricefields, ponds T. !eerj Bleeker -do- 1938 swamps -do- population Continued HelostomaOsphronemus temminckiCuvierLacepede(pearl gouramy & plasalid)Valenciennes(giant gouramy) Bangkok,IndonesiaJava 1927 pondsLakes, ricefields -do- Thailand 1948,1950 Catfishes (Kissing gourami) Bogor, Indonesia 2'567'521950 NaturalPonds waters and other Diseases/Parasites ClariasIctalurus batrachus calus(Thai(Linnaeus) catfish) catfish ThailandCalifornia, USA 197210'35 Ponds Pangasiu.sIctalurus punctatus sutchi(Pla(Channel swai) catfish) ThailandCalifornia, USA 198519781974 Ponds,Reservoirs reservoirs Localized distribution MicropterusFamilyClarias CENTRARCHIDAElazera sal,noidesLe(African Suer (Blackcatfish) bass) California,Thajwan USA 19151970 Reservoirs,Ponds lakes ExperimentedLocalized distribution 1958 L.LepomisM. cyanellus salrnoidesfloridatzus macrochirusRafferty(Florida (blue bass) gills) California,1985 USA -do- Reservoirs1950 Swamps, highland -do- Localized distribution

Opegaster ,nininia Clinostomoides(intestine) opehicephal Clinosiomoides brieni encysted in gills and opercular cavity Table 1. ContinuedTaxonomic status Introduced Habitat Present Status Diseases/Parasites MirgurniisFamily COB1TIDAE aguil1icadatu(Canton (Loach) or From Year whetherfish) Japan Before 1937 Highland rivers, ricefields Lo'alized distribution naturally breeding Family POECIILIDAE population Gambusia affinisBaird and Girard Honolulu, Hawaii 1905 1913 Brackishwater (Top minnow or Ponds Mollienesia lalipinnaLemosquitofish) sueur (top minnow Honolulu 1914 Brackishwater or mosquitofish) Hawaii ponds MolluscsPoeciliaFundulus (Mollienesia) heteroclilusreticul(mosquitofish) ala (mosquito fish) -do--do- 1905 Ampularia gigasGolden(kuhol) miracle snail Florida, USA 1980 River, ponds lakes, imgation Commercial fisheiy, natural breeding, 1s, ncefields, Crislaria plicata caipsintroductionwithAccidential (?) Asiatic Lake fishpens/cages Penaeid Shrimps (L de Bay) Naturally breeding Penaeus vanameistylirostris 19801980(?) (?) Introduction of Exotic Aquatic Species in Singapore

L.M. CHOU T.J. LAM Department of Zoology National University of Singapore Kent Ridge, Singapore 0511

Chou, L.M. and T.J. Lam. 1989. Introduction of exotic aquatic species in Singapore, p. 91-97. In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pub!. 3, l54p. Asian Fisheries Society, Manila, Philippines.

Urbanization has changed much of Singapore's landscape and affected its natural fauna. Exotic species have been introduced for economic or commercial purposes. Two such species that have become firmly established in Singapore's inland waterways are the guppy (Poecilia reticulata) and the tilapia (Oreochromis mossambicus). The country lacks extensive natural inland water bodies as well as indigenous inland fisheries, and the introduction of exotic species is not likely to cause much concern. No serious study on the ecological impact of introduced species has been made.

The natural landscape of Singapore has changed drastically since the island's founding in 1819. During the early days, large tracts of forests were cleared by industrious cultivators and replaced by plantations of pepper, coffee, rubber, sugar-cane, gambier and other crops. As urbanization continued, remaining forests as well as disused and existing agricultural land were systematically cleared at increasing pace for commerce, industry and housing. Today, 28.6 km2 of nature reserves and secondary forests surrounding the reservoir catchment areas remain while land for agrotechnological use such as for agriculture and aquaculture, has been designated in ten parks intended for farming at high technology level. These parks occupy about 180 hectares, and the area is expected to increase to 2000 hectares over the next decade (Yap 1987). The drastic changes in the environment affected the natural fauna of the island. Some species of plants and animals were reduced or even exterminated. At the same time these changes favoured the proliferation of other species that were introduced accidentally or intentionally. Some of the exotic species were brought in and raised for their ornamental, economic or commercial potential. This included indigenous ones which would otherwise have been exterminated had they not been introduced for the reasons mentioned. This paper will deal only with the aquatic animal species. No studies have been made on the ecological significance and implications of introduced species. Aspects such as parasite and other disease introduction and transmission, their effect on the environment, and the competition of introduced species with indigenous ones have not been given attention, but warrant systematic investigation. In cases where the ecological impact of an introduced species can be predicted legislative and other measures have been taken by the government to stop their entry. An example of this is the ban on the import of piranhas under the

91 92

Fisheries (Piranhas) Rules 1971, enacted as a supplement to the Fisheries Act, 1966. It is now illegal to rear or release the fish into natural waterways.

Species Introduced for Biological Control The only species recorded as having been introduced for biological control is the guppy, Poecilia reticulata. This species was introduced in 1937 for mosquito control (Herre 1940) and has since become well established in polluted waters having free ammonia concenirations of a few hundred parts per million (Johnson 1973).

Species Introduced for Culture

Freshwater Species

Trionyx sinensis (Chinese soft-shell terrapin)

In the early 1970's, some hatchlings were brought in from Taiwan by an enterprising farmer to test the viability of the species in Singapore. It adapted well to the tropical conditions. Because of its higher fecundity and faster growth rate under these conditions, it is now cultured in preference to the slower-growing native species, T. cartilagineus. Endemic to China, T. sinensis has been successfully cultured for over 60 years in Japan and 100 years in Taiwan. The warm climate in Singapore allows a higher production rate than in the temperate region, but its culture is land intensive. Therefore, although Chinese soft-shell terrapin farming is lucrative in Singapore, it is limited to two farms. There have been cases of escape of these terrapins into inland water systems. Although the implications have not been considered, there is every likelihood of some ecological disturbance because of their ability to reproduce faster in the tropics, and their voraciousness (live fish forming the main part of their diet), especially if they find their way into sheltered waters where fish are stocked, such as reservoirs.

Crocodilus porosus (estuarine crocodile) and

Tomistoma schiegeli (Malayan gavial)

Sharma (1973) reported that it was unlikely for any large individuals of Crocodylusporosus to be found in the wild although they were a major hazard in coastal waters and mangroves in the earlier days. The presence of the Malayan gavial in Singapore waters although rumoured, has never been substantiated. Both species have together with other crocodilian species, been reintroduced for farming. Their escape always causes great concern because of the apparent danger to man and occasional escapes have occurred. 93

Oreochromis mossambicus (common tilapia)

The very hardy tilapia was introduced by the Japanese Army during their occupation of Singapore from 1942-1945 (Harrison and Tham 1973). The constant warm climate enabled the species to breed rapidly all year round. It was not well received as a foodfish and has since become free-roaming, with feral populations inhabiting freshwater and low-salinity habitats. Most of the populations now consist of stunted individuals (Johnson 1973). The impact of this fish on the environment is yet to be fully assessed but it appears to have dominated reservoirs and man-made lakes. Khoo et al. (1977) have estimated the tilapia population in the Seletar Reservoir to consist of 10.2 million juveniles and 10.3 million adults in 1975/76. Mass mortality occurred in 1972 (about 300,000 died between October and December) due apparently to sudden oxygen decline as a result of mixing of oxygen-stratified water layers caused by climatic changes.

Carps Common carp, Cyprinus carpio, Chinese carps, comprising Ctenopharyngodon idellus (grass carp), Aristichthys nobilis (bighead carp), Hypophthalmichthys molitrix (silver carp); and Cirrhina molitorella (mud carp). Chinese carps were introduced by the Chinese immigrants during the early history of Singapore. Their culture in ponds was on a restricted scale, with fry imported from China and timed such that harvests coincided with Chinese festivals. After the Second World War, the dramatic increase in cost of marine fish made the cheaper carps a popular food item. Their culture was subsequently stepped up to produce the fish the year round (Tham 1975). Gradually, increasing land demand led to a decline in carp culture as ponds were reclaimed. Carp culture is now confined to less than 100 hectares of ponds with prospects of further decline and to the reservoirs such as Seletar Reservoir where bighead carps are reared in floating cages without supplementary feeding to reduce algal and nutrient load as the fish feed on plankton.

Marine species

Finfish

None of the finfish species imported for culture can be considered as exotic as they can also be found in local waters. These are mainly the grouper, Epinephelus salmoides, and seabass, Lates calcarifer (Anon 1986). The impact of culture of large numbers of these fish in 65 floating fish farms in coastal waters with the attending possibility of escape and spontaneous breeding, on the environment is not known. As local collection from the wild and hatchery production are still insufficient to support the industry, seabass and grouper fingerlings have to be imported from mainly Thailand and the Philippines. As with all imported species, the potential danger from diseases is present and the possibility of introduction of new strains of pathogens exists. However, ectoparasites found on imported fingerlings are probably similar to those found locally and it is likely that these parasites were absent prior to fish importation. Other species cultured on a smaller scale because of the lack of seed supply include snappers (Lutjanus johni, L. argentimaculatus), coral trout (local red grouper, Plectropomus maculatus), yellowfish jack 94

(Caranx ignobilis) golden trevally (C. speciosus), and siganids (Siganus canaliculatus, S. guttatus). Other species not commonly found or not existing locally but could be considered for culture are other groupers such as the tiger grouper (E. microdon) imported from Indonesia and cultured with some success, and the HongKong red grouper (E. akara). The red tilapia hybrid (Oreochromis niloticus hybrid) has been introduced for marine culture by some farmers using originally freshwater stocks acclimated to sea water conditions. Marine stocks may become available in the future. The fish has also been stocked in limited numbers (8000 fry) into the Singapore River, together with 560,000 banana prawns (Penaeus merguiensis) and 34,000 sea bass (L. calcarifer) (L. Cheong personal communication). The impact of this stocking is still uncertain.

Shellfish

The healthy market for prawns and limited land availability has encouraged farmers to culture prawns (P. merguiensis) semi-intensively in brackishwater ponds insteadi of trapping them by the traditional method. The Kuruma prawn (P. japonicus) has been imported by a Japanese company and initialtrials in lined ponds and at intensive stocking have been sufficiently encouraging for commercial farming to be initiated. Other penaeid species such as P. monodon (tiger prawn), and foreign ones such as P. stylirostris (blue prawn), P. vannamei, P. esculentus (brown tiger prawn), P. orientalis (Oriental prawn) and P. indicus (Indian prawn) may be considered, if environmentally and economically suitable for culture. The tiger prawn, although indigeneous is not easily available, and culture is restricted because of the lack of suitable salinity conditions. The spiny lobster most popularly cultured because of itsavailabilityisPanilurus polyphagus, although other species from neighbouring countries could be imported if available in large enough numbers for culture. It is unlikely that their escape from the farni; will allow them to establish significantly in some of the marine habitats like coral reefs as they are much sought after by fishermen, collectors and enthusiasts. The indigenous mangrove crab (Scylla serrata), originally from mangrove areas, and previously cultured on small scale in narrow earth furrows in the vicinity of traditional prawn ponds, are now imported for culture in wire cages at some commercial floating fish farms due to the rapid reduction of mangrove forests. They are imported from Sri Lanka and Indonesia and kept in the cages for around two weeks to fatten, and then sold locally. It is unlikely that there is sufficient wild-caught stock for this purpose, and the reduction of mangrove areas in Singapore to less than 250 hectares will have contributed to the scarcity of the mangrove crab.

Species Introduced for Ornamental Value

Johnson (1964, 1973) reported 5 species of freshwater fishes which have been introduced. Puntius semifasciolatus was accidentally introduced from China and being tole:rant, is well established in the catchment area. Small populations of the true fighting fish, Betta splendens, have established in Jurong Lake and water bodies in the Sembawang area. Also well-established in the wild is the introduced Trichogaster pectoralis, while the mollies, Poecilia sp henops and Poecilia affinis, have established permanently in low salinity waters. 95

Many other species of ornamental fish are imported and/or farmed in Singapore (Table 1). Accidental escape or even deliberate release of these species into natural waterways is likely but the impact, if any, is not noticeable. They are probably unable to compete with the hardier feral guppy and tilapia.

Discussion

Singapore does not have extensive natural inland water bodies nor does it havean indigenous inland fisheries. There is also at present hardly any unique inland aquatic fauna to protect either. As such, introduction of exotic species does not cause much concern and there has not been any serious study of the impact of species introduced for farming or other purposes. However, two introduced species appear to have firmly established in Singapore's inland waterways, and these are the guppy (P. reticuluta) and the tilapia (0. mossambicus).

Acknowledgement

We would like to thank Mr. Robert Lee, Mr. Leslie Cheong and Mrs. Audrey Yuen of the Primary Production Department of Singapore for providing us with some of the information in this paper.

References

Anon. 1986. Manual on floating netcage fish fanning in Singapore's coastal waters. Fisheries Handbook No. 1, Pnmasy Production Department, Minisuy of National Development, Republic of Singapore. Harrison, IL. and A.K. Tham. 1973. The exploitation of animals, p. 251-259. In Chuang, S.H. (Cd.) Animal life and nature in Singapore. Singapore University Press, Singapore. Herre, A.W.C.T. 1940. Additions to the fish fauna of Malay and notes on rare or little known Malayan and Bomean fishes. Bulletin Raffles Museum Singapore 16: 27-61. Johnson, D.S. 1964. An introduction to the natural history of Singapore. Rayirath (Raybooks) Publications, Singapore,p. 106. Johnson, D.S. 1973. Freshwater life, p. 103-127. In Chuang, S.H. (ed.) Animal life and nature in Singapore. Singapore University Press, Singapore. Khoo, H.W., S.L. Yang and C.J. Cioh. 1977. A preliminary limnological study of Seletar Reservoir. Journal of Singapore National Academy of Science 6: 1-11. Sharma, R.E. 1973. Noxious and toxic animals, p. 229-250. In Chuang, S.H. (ed,) Animal life and nature in Singapore. Singapore University Press, Singapore. Tham, A.K. 1973 Fish and prawn ponds, p. 260-268. In Chuang, S.H. (ed.) Animal life and nature in Singapore. Singapore University Press, Singapore. Yap, H.B. 1987. More farmland in agrotech parks for tender. Primary Production Bulletin No. 274, May 1987: 1. 96

Table 1. Main species of aquarium fish imported into Singapore (infonnation kindly provided by the Primaiy Production Department of Singapore).

Freshwater Fish Freshwater Fish Cichlid Acarichthys heckelii Angel Plerophyllus allus Aequidens curviceps Pterophyllus scalare Aequidens maroni Aequidens puicher Barb Acrossocheilus bantamensis Aequidens let ramerus Barbodes birnaculalus Apistogramma ramirezi Barbodes everetti Apistogramma sp. Barbodesfasciatus Astronotus ocellalus Barbodes hassecti Aulonocaro .sp. Barbodes hexazona Chromidotilapia sp. Barbodes lateristriga Cichiasoma cynogula/tus Barbodes partipenlazona Cichlasomafestivwn Barbodes schwanenfeldi Cichiasoma meeki Barbus arulius Cichiasoma nigrofascictus Barbus binotatus Cichiasoma severum Barbus cumingi Chiclasoma sp. Barbusfilamenlosus Geophagus sp. Barbus holotaenia Haplochromis sp. Capoeta arulius Hemichromis bimacuiatu.s Capoeta chola Hemichromis sp. Capoeta oligolepis fodotropheus sprengerae Capoeta semifasciolatus Jordane/lafloridae Capoeta let razona Labeotropheus sp. Capoeta lilteya La,nprologus sp. Esomus dannica Melanochromis sp. Osteochilus hasselti Nannochromis nudiceps Osteochilus vitattus Nannochronsis sp. Puntius asoka Pelmatuchromis kribensis Puntius conchonius Pseudotropheus aura rus Puntius curningi Pseudotropheus zebra Puntiusfilarnentosus Pseudolropheus sp. Puntius gonionotus Steal ocranus casuarius Puntius lineal us Symphysodon aequifasciata Puntius nigrofasciatus Tilapia aurea Puntius sachsi Tilapia sp. Puntius schwanenfeldi Uaru amphiacanthoides Puntius semifasciolatus Punlius stigma Molly Poecilia latipinna Tanichthys albonubes Poecilia sphenops Poecilia velifera Guppy Poecilia reticulata Goldfish Carassius auratus aielus Swordtail Xiphophorus helleri Tetra Anoptichthysjordani Platy Xiphophorus maculatus Aphyocharax rubripinn is Xiphohorus variatuS Astyanaxfasciatus mexicanus Astyanax mexicanus Gouramy Belontia signata Cheirodon axelrodi Colisa chuna Gymnocorym bus terneizi Colisafasciata Hasemania nanas Colisa labiosa Hemigrammus caudoeitiatus Colisa lalia Hemigranmus erythrmonus Helostoma rudolfi Hemigrammus gracilis Macropodus opercularis Hemigrammus ocellifer Osphronemus goramy Hemigram,nus pulcher Sphaerichthys osphromenoides Hemigrammus rhodostomus Trichogaster leeri Hyphessobrycon bento:?i Trichogaster microlepis Hyphessobrycon bfasciatus Trichogaster pecloralis Hyphessobryconflamsreus Trichogaster Irichopterus Hyphessobrycon herhetaxelrodi Trichogaster sp. Hyphessobrycon pulchripinnis Trichopsis vitt at us Hyphessobrycon rosac'us Hyphessobrycon rubro.stigma Hyphessobrycon schol2ei Hyphessobrycon serpa? Continued 97 Table 1. Continued

Freshwater Fish Freshwater Fish Megalamphodus megalopteriss Carp Aristichthys nobilis Metynnis maculatus Carassius gibelio Metynnis roosevelti Cienopharyngodon idella Micratestes interrupt us Cyprinus carpio Moenkhausia oligolepis Hypophthalmichthys molitrix Nematobrycon amphiloxus Paracheirodon innesi Scat Scat ophagus argus Prionobramafihigera Prisiella riddlei Eel Electrophorus eleciricus Thayeria obliqua Fluta alba Macrognathus aculeatus Leach Acanthophihalmus myersi Mastacembelus ,naculatus Acanthophthalmus semicinctiss Mastacembelus sp. Acarahopsis choirorhynchus Botia horae Scissor Tail Rasbora caudimaculata Botia hyinenophysa Botia macracantha Catfish Brochis coeruleus Botia modesta Chacasp. Botia sidihimunki Corydoras aeneus Cobitis iaenia Corydoras hasiatus Noemacheilus botia Corydorasju!ii Noemacheilusfasciatus Corydoras melanistius Noemacheilus kuiperi Corydoras melanislius brevirostris Corydoras myersi Danio Brachydanio albolineatus Corydoras naitereri Brachydaniofrazkei Corydoras paleatus Brachydanio malabaricus Corydoras xinguensis Brachydanio rerio Hypostomus plecostomus Danio malabaricus Kryptopterus bicirrhis Kryptopierus macrocephalus Discus Symphysodon aequfasciaia aequjfasci Leiocassis siamensis Symphysodon aequzj'asciata axeirodi Leiocassis sp. Symphysodon aequifasciata haraldi Malapterurus eleciricus Symphysodon discus Microglanis arahybae Mystus tengera Fighting Fish Betta bellica Ompok hi maculat us Betta brederi Pangasius sanitwongsei Betta splendens Pangasius sutchi Synodontis nigriventris Shark Balantiocheilus snelanopterus Synodontis notatus Labeo bicolor Synodontis sp. Labeo erythrunus Labeo variegatus Marine Fish Lepiobarbus hoeveni Morulius chrysophekadion Gown Butterfly Algae Eater Gyrinocheilu.s aymonieri Damsel Tang Harlequin Rasbora dorsiocellata Peacock Lion Rasbora einthoveni Trigger Rasbora elegans Wrasse Rasbora heteromorpha Surgeon Rasbora kalochrorna Rasbora macuiala Rasbora pauciperforala Rasbora sieineri Rasbora taeniata Rasbora trilineala Rasbora vaterfloris

Mono Mohodactylus argenteus Monodactylus sebae

Bumble Bee Brachygobius sp.

Status of Introduced Species in Sri Lanka

SENA S. DE SILVA Departments of Fisheries Biology and Zoology University of Ruhuna Matara, Sri Lanka

De Silva, S.S. 1989. Status of introduced species in Sri Lanka, p. 99. In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines.

Much has been written on the introduced species and their impact on the fisheries of Sri Lanka in the last two decades. As such no attempt is made here to deal with this subject, again, as there is very little available in the way of fresh information. The readers are therefore, directed to the following references.

De Silva, S.S. 1985. Status of the introduced cichlid Sarotherodon mossambicu.s (Peters) in the reservoir fishery of Sri Lanka: a management strategy and ecological implications. Aquaculture and Fisheries Management 16: 91-102. De Silva, S.S. 1987. Impact of exotics on the inland fishery resources of Sri Lanka. Archives Hydrobiologie Beiheft, Ergebnisse der Limnologie 28: 273-293. Fernando, C.H. 1971. The role of introduced fish in fish production in Ceylon's freshwater, p. 295-310. In E. Duffey and A.S. Watts (ed.) The Scientific Management of Animal and Plant Communities for Conservation. Blackwell Scientific Publications, Oxford, England. Fernando, C.FI. and H.H.I. Indrasena. 1969. The freshwater fisheries of Ceylon. Bulletin Fisheries Research Station, Ceylon 20: 101-134.

99 /00 Exotic Aquatic Species in Taiwan

I-CHIU LIAO Taiwan Fisheries Research Institute 199 Hou-Ih Rd., Keelung 20220 Taiwan HSI-CHIANG LIU Institute of Oceanography College of Science National Taiwan University Taipei, Taiwan

I-Chiu Liao and Hsi-Chiang Liu. 1989. Exotic aquatic species in Taiwan, p. 101-118. In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec, Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines.

There are 38 aquatic species known to have been introduced to Taiwan. The earliest introductions were probably those of the Cyprinidae family, although documentation to this effect is lacking. Other more recently introduced species, like the tilapias, are relatively well documented. Some of the introduced species have been successfully cultured. The introductions are discussed and, where information is available, a more detailed history, including problems, if any, is presented. The problem of the lack of consolidated information is also discussed.

Distances in the world today have shrunk considerably due to the improvements in transportation and communication technology. Under such conditions, many species of aquatic organisms have been transferred to regions of the world where they are not naturally occurring. The term "exotic" species refers to any species introduced by man from a foreign land (McCann 1984). This should not be confused with "transplanted" species - native species moved by man into an ecosystem outside their native range, but still within their country of origin, and with "nonnative" species - any species introduced by man into an ecosystem outside its original native range, including both exotic and transplanted (McCann 1984). Of special interest in this report are exotic aquatic species known to have been introduced to Taiwan at different times. However, it would be useful to mention at this point, the particular case of two species in Taiwan, which would be hard to categorize in the context of the above definitions. One is Penaeus monodon or grass prawn. This species is native to Taiwan, but since insufficient spawners were available locally, about a decade ago, Taiwan began importing great numbers of adult P. monodon from neighboring countries, like the Philippines and Malaysia, and induced these adults to spawn. Most of the P. monodon that have been cultured here were spawned from adults obtained from abroad. The other is Plecoglossus altivelis, commonly known as "sweet fish" or "ayu". It is an indigenous species in Taiwan, but became extinct in the 60's. It only began repopulating local waters when Japan introduced it several years hence. Perhaps in the future, more accurate and exact definitions of such terms should be formulated and internationally agreed upon - to cover special cases such as that of P. monodon and P. altivelis.

101 102

Table 1 lists various species known to have been introduced to Taiwan at different times. An assessment of the status of these species, based on five criteria, is presented in Table A.II.8, in the Appendices to this volume. This assessment table (as well as Table 1) was limited to major food fishes only, as this was the focus of the workshop in which this report was presented. However, a list of ornamental fishes introduced into the country is given in Annex I.

Status of Introduced Species Many of the exotic aquatic species introduced into Taiwan, such as the tilapias, have been greatly beneficial. A few, like the giant African snail, Achatina fulica, and the apple snail, Ampullarius insularu,n, have caused serious damage to the local environment. The more information is documented on introductions of exotic species, the easier it will be to monitor their consequences and the government will be able to manage the country's fisheries resources and aquaculture industry better. It is regrettable that the history of introductions of exotic aquatic species into Taiwan has not been well recorded. This report is the result of an initial effort to collect and compile whatever information is available from various, scattered sources. It is far from complete. Hopefully, other colleagues can gradually build upon the modest foundation that it has attempted to lay down.

Finfish

Gambusia affinis

Gambusia affinis or topminow was introduced from North America to Taiwan in the early 20's. It is generally accepted that this species was introduced to control malaria. It spread all over Taiwan as a wild fish and also came to be considered as a good experimental fish.

Oreochromis mossambicus

Oreochromis mossambicus or Mozambique tilapia was originally imported fromIndonesia by the Japanese in 1944, when Taiwan was still under the Japanese occupation. However, its culture failed. In 1946, it was brought back into the country under rather peculiar circumstances, and not as a deliberate introduction for scientific research or culture purposes. Two Taiwanese men named Wu and Kuo had been commissioned as Japanese soldiers during the Second World War. When the war was over, and they were released from military service, they returned home to Taiwan with several 0. mossambicus which they took from Singapore as souvenirs, of which 13 survived. Since then, this species of tilapia was cultured successfully and became very popular in Taiwan. In memory of its "accidental" introducers, it was called "Wu-Kuo yu", yu being the Chinese word for fish. It is true that this species has a number of weak features. For instance, it is not very resistant to low temperature, it spawns too fast, and when it matures, its color turns black, making it quite unattractive and not so acceptable to consumers. But because it grows fast, produces a high yield, and is a sturdy fish, it was readily accepted by the Taiwanese fish farmers and consumers as a cheap and available source of protein immediately following World War II. This fact is to be 103 appreciated in the context of the widespread poverty and hunger, which were the aftermath of the war. Other specimens were imported in 1981 from the Republic of South Africa (RSA) for the purpose of studying cross-breeding. In Taiwan, this species was initially crossed with 0. niloticus male. The result is a popular hybrid with rapid growth, large size and much better appearance (Kuo 1969). The Taiwanese call this hybrid "fu so yu", fu so meaning "lucky, longlife".

Salmo gairdneri

Salmo gairdneri or rainbow trout was first introduced from Japan in 1957. Three thousand fertilized eggs of this species were released into a reservoir, where most probably perished. In 1959 and 1960, 200,000 'eyed' eggs were introduced (each year), but again, all perished. Finally, in 1961, 50,000 'eyed' eggs were imported, hatched and reared to adult stage at Ma-Lin, a research station of the Lukang Branch of the Taiwan Fisheries Research Institute TFRI) (Chen 1976). This hatchery has been in operation from that time until the present. Aside from this research hatchery, a number of commercial hatcheries for this species also currently exist in Taiwan. The difficulties encountered in its culture in Taiwan have to do mainly with the need for an adequate cold water supply. It commands a good price, but the volume of production is limited by the lack of appropriate culture areas, i.e., those with abundant supply of cold water, and this also limits expansion.

Tilapia zulu Introduced from RSA in 1963 by Tang, Tilapia zulu or redbelly tilapia never gained much popularity due to its small size, slow growth and aggressive behavior towards other fish (Chen 1976; Liao and Chen 1983). Also, it does not taste very good and is not suited for polyculture. The main reason for its introduction was to cross-breed it with 0. rnossambiciis. T. zulu is relatively cold-resistant as compared with 0. mossambicus, and it was hoped that a more cold- resistant hybrid would result. Sixteen fish had been introduced but the species never did become popular for culture.

0. niloticus 0. niloticus or Nile tilapia was introduced from Japan by Yu and Imai in 1966 (Chen 1976; Liao and Chen 1983). Fifty-six individuals were originally introduced. By itself, 0. niloticus makes a fine culture species, and it also produces good results when crossed with 0. mossambicus. But so far, the best result is achieved when it is crossed with 0. aureus males; predominantly male and much larger offspring are produced. 104

Pangasius sutchi

Pan gasius sutchi or pangasius catfish was introduced from Thailand in 1969 by Ling (Chen 1976). It cannot tolerate the cooler climate of Taiwan, but it has high tolerance for low oxygen content. It is quite palatable and larger than the local species of catfish, Clarias fuscus. Also, it has a very efficient conversion rate, even if itis given only tilapia feed. However, its acceptability has suffered somewhat because people mistake it for the sea catfish, Anus maculatus (Thunberg), which closely resembles it in appearance,but which is of much poorer quality. After its introduction, it was experimentally cultured at a government-run pilot farm. At present, though, it has come to be used more as an ornamental fish than a food fish.

Clarias batrachus

Clarias batrachus or walking catfish was introduced in 1972 from Thailand (Chen 1976). It is known for its fast growth rate. One fish can reach up to 2 kg in one year. Although C. batrachus is also generally regarded as a pest (Welcomme 1984), it has nonetheless achieved considerable popularity. It has apparently cross-bred with the native species C. fuscus, resulting in a hybrid that has spread all over Taiwan, to such an extent that C. fuscus is now in danger of extinction.

0. aureus

0. aureus or blue tilapia was introduced from Israel in 1974 by Liao, Huang and Tseng with the assistance of Pruginin (Chen 1976; Liao and Chen 1983). The 83 specimens importedwere intended for obtaining all-male offspring when crossed with 0. niloticus females. The resulting hybrid is now the tilapia mainly cultured in Taiwan; it provides a fine example ofsuccess achieved with exotic aquatic species. Annual production of this hybrid currently.exceeds 50,000 tonnes.

Ictalurus punctatus Ictalurus punctatus or channel catfish was introduced from the U.S.A. in the mid 70's. However, the warmer climate in Taiwan is not very suitable for its culture. It is alsovery sensitive to water quality, such as that resulting from pollution. Not being so popular, this species is no longer cultured.

Anguilla anguilla

Anguilla anguilla or European or French eel was introduced to Taiwan around 1976 (Chen 1976). It is native to Europe and at the time of its introduction, it was considered as a promising species for culture. Although A. japonica, the native species, is a good culture species, and the technology for raising it was well understood by the local aquaculturists, the inability to produce adequate quantities of this species prompted the introduction of A. anguilla. 105

However, A. anguilla cannot tolerate the high temperature in Taiwan and has been infected by many diseases and parasites, resulting in its slow growth. Survival rate under culture was usually low. As a result of these disadvantages, prospects for the culture of this species locally are not very bright.

Leptobarbus hoevenii

Leptobarbus hoevenii, also known as barb or sultan fish, was introduced to Taiwan in 1979 from Indonesia. Currently, it is being experimentally cultured at the Lukang Branch of TFRI. Another species, which has not yet been identified, but which could be L. hosei, was also introduced at a later date. It is smaller than L. hoevenii, but is much easier to mass produce. Because of this, it has attracted the interest of many aquaculturist.

Megalobrama amblycephala Megalobrama amblycephala or Wu-chang fish was introduced from mainland China in 1979 and generally remained unpopular among culturists. Another Megalobrama species may have been inadvertently introduced, although it has not yet been identified. Both species are so bony and thus are not very much appreciated by local consumers. Lately, M. amblycephala has been used for cross-breeding with the Ctenopharyngodon idellus.

Micropterus salmoides A fish native to North America, Micropterus salmoides or largemouth bass was introduced to Taiwan in the late 70's. In other countries where M. salmoides has also been introduced, it was reported to have endangered or actually caused the extinction of certain indigenous species. In Taiwan, however, the techniques for artificial propagation of M. salmoides have been established and improved, and this fish has rapidly gained popularity. Much care has been taken so that this fish is used only for monoculture, and not stocked in natural waters. M. salmoides was easily accepted and liked by Taiwanese consumers. At present, it is cultured in several places in Southern Taiwan and is even exported to Hong Kong.

Red tilapia There is a local red tilapia strain in Taiwan, which is different from and should not be confused with the exotic Oreochromis sp. Thirty specimens of the latter were introduced in 1979 by Liao, Chao, Chen, Huang, and Liu, with the assistance of Yeh, from the Philippines, where it is also exotic (Liao and Chen 1983). This exotic Oreochromis strain was introduced here to be used in genetic studies and cross-breeding. 106

0. hornorum

This species is also known as wami tilapia. It was introduced from Costa Rica in 1981 by Huang and Yeh. The objective of the introduction was to obtain monosexprogeny by hybridization with other Oreochromis spp. All the hybridization attempts have been successful in producing all-male offspring, and the hybrids are now being used for extension. However, these hybrids are smaller in size than 0. niloticus and 0. aureus hybrids.

T. rendalli

T. rendalli or red breast tilapia was introduced from RSA in 1981 by Liao, Sch.00nbee and Clark (Liao and Chen, 1983). All 25 specimens were introduced for the mere purpose of adding a new species to the local gene pool.

Colossoma bidens

Colossoma bidens or freshwater pompano was introduced from Brazil probably around 1986. It is currently being cultured experimentally and appears promising. However, there is often a negative impression of this fish because of its similarity to the aggressive piranha, Pygocentrus piraya, and this can hamper its extension.

Sciaenops ocellatus

Sciaenops ocellatus or red drum was introduced in 1987 by Liao, Huang, Lee and Arnold from the United States. This species has an impressive growth rate, and although it is still inan experimental stage of culture, it shows much promise.

Cyprinidae

The following cyprinids are generally believed to have been introduced several centuries ago from mainland China, although exact dates of introduction were not recorded. Aristichthys nobilis or bighead carp Carassius auratus or crucian carp Cirrhina molitorella or mud carp Ctenopharyngodon idellus or grass carp Hypophthalinichthys molitrix or silver carp Mylopharyngodon piceus or snail carp. Collectively, they are referred to as the "Chinese carps". The year 1963 was a milestone in Chinese carp culture; during that year, Taiwan succeeded in devising the techniques for induced spawning of these Chinese carps. Prior to 1963, they had to be introduced yearly from mainland China, through Hong Kong, because fry were always in short supply. Another carp, Cyprinus carpio or common carp, was introduced long ago from Japan and is also being commercially monocultured. 107

Today, most of these carps are polycultured commercially with considerable success, and their fry are exported in substantial volumes. Annual production of all these carps, put together, is currently 30,000 t.

Crustaceans Macrobrachiusn rosenbergii Macrobrachium rosenbergii, also known as Malaysian prawn or giant river prawn, was introduced in 1970 from Thailand by Ling. From one male and one female, the only survivors from the entire shipment, thousands have been bred, spurred by the success achieved at the Tungkang Marine Laboratory (TML) of TFRI (Liao et al.1973). This has facilitated the development of a relatively successful enterprise. Its monoculture makes up a big industry. Lately, M. rosenbergii has peculiarly become a popular species for game fishing in Taiwan.

Penaeus stylirostris

Penaeus stylirostris or blue shrimp was introduced from Panama in 1979 by Perysn and Lee (Liao and Chao 1983). It was the first saltwater prawn species introduced to Taiwan. Of the 500,000 nauplii introduced, 50,000 were brought to TML, where they were successfully reared to the adult stage. However, there were difficulties met on inducing it to mate. As a result, this species has become extinct.

P. vannawi P. vannamei or white leg shrimp was the second exotic shrimp introduced to Taiwan. In 1981, 86 young P. vannamei were brought by Huang from Panama. Although this species grows well in Taiwan, it is hard to induce the shrimp to mate in captivity. Furthermore, this species is known to have latent infectious hypodermal and hematopoietic necrosis or IHHN (Bell and Lightner 1984), and this presents potential problems. Thus, care must be taken to identify the source of the P. vannamei introduced.

P. brasiliensis P. brasiliensis, also known as red spotted shrimp or Guiyana pink, was introduced in 1981 by Liao and Chao with the assistance of Instituto de Pesquisas de Marinha and Chang of Brazil (Liao and Chao 1983). Its culture has been intensively experimented, though only a size of 40 g was attained after a one-year growout (Liao and Chao 1983). Unfortunately, there are no more surviving P. brasiliensis in Taiwan. 108

P. schmitti P. schmitti or southern white shrimp has been introduced from Brazil by Liao and Chang and is experimentally cultured. Unfortunately, efforts to propagate this species have failed.

Molluscs Achatinafulica Achatinafulica or giant African snail was introduced from Singapore in 1932. This species has propagated and has become a pest to agriculture.

Ampullarius insularum

The mollusc Ampullarius insularum or apple snail was introduced into Taiwan in 1979 from Argentina. It was adopted for culture, but it has become more of a pest. Its eggs, conspicuously coloured bright red, now seem to be found in almost any body of water in Taiwan, creating a considerable problem when they hatch, because they cause widespread damage to ricefields.

Seaweeds Laminaria japonica

Laminaria japonica, also known as kelp or konbu, was first introduced from Japan in 1976. Currently, it is cultured in small scale, mainly in the northern part of Taiwan.

Undaria pinnatifida and U. undaroides

Undaria pinnatijlda and U. undaroides or wakame were introduced from Japan in 1981 by Chiang. They are now commercially cultured in Quemoy and Peng-hu islands as well as in northern Taiwan. Both species show bright prospects for interested culturists.

Reptiles Rana catesbeiana

In 1924, before World War II, when Taiwan was a Japanese-occupied territory, the Japanese introduced the Rana catesbeiana or American bull frog to Taiwan. The first introduction was not successful because the farmers who reared the frogs became discouraged and abandoned the project. After the war, in 1951, it was reintroduced from Japan by TFRI and distributed to interested farmers. The attraction of frog culture is that little capital investment and space are required. Thus the interest could be shared by rural and city dwellers. Rana catesbelana has now become a very popular culture species. 109

Caiman latirostris and Alligator mississippiensis

Caiman latirostris or caiman is commercially cultured in Taiwan under intensive conditions. Alligator mississippiensis or alligator is also commercially cultured, but under semi-intensive conditions. Both of these reptiles are already part of a budding industry in Taiwan and probably hold good prospects for the future.

Discussion Usefulness of introductions

When properly planned, recorded, documented and managed, introductions of exotic aquatic species can be very beneficial. One successful introduction in Taiwan (aside from the tilapias) involves Plecoglossus altivelis - that is, assuming it falls under the definition of "exotic" or "introduced" species. It was originally a native species in Taiwan, but as a result of manmade damage to its environment, the populations decreased greatly, and eventually, this species disappeared completely. Eyed eggs were then introduced from Japan and under the guidance of research institutes and the protection of game fishing clubs, Taiwan's reservoirs and rivers were once again restocked with P. altivelis. Several other species, such as M. rosenbergii and R. catesbeiana, are also very popular and commercially important. Before the recent heavy industrialization of Taiwan, these species helped in improving the social and economic conditions of a big number of aquaculturists. The culture of these species had a very visible social impact on the country. Their popularity and commercial viability are also demonstrated in other parts of the world.

Exercising caution Many other exotic species, out of the 38 mentioned above, turned out to be successful introductions. These species have the proven qualities for culture in most conditions and are generally quite popular. One important factor which enhanced the success of these introductions was the careful and systematic process in which they were carried out. Without such careful testing, the consequences could be quite detrimental, as in the case of the two snails, Achatina fulica and Ampullarius insularum. However, caution must still be exercised, even with successfully introduced species. The case of the tilapias is an example of the benefits and dangers of introduced species. Although the tilapias offer many advantages as a culture species, and most tilapia introductions into Taiwan (see Table 2) have been successful, it is important to note that tilapia introductions into other countries have been blamed for the transfer of certain parasites. For instance, six species of Cichlidogyrus (gill flukes) were transferred from Africa to Israel as a result of tilapia introductions (Hoffman and Schubert 1984). This is a potential threat and should be considered whenever tilapia is being introduced. Furthermore, 0. mossambicus, T. rendalli and T. zulu are generally regarded as pests when introduced as exotic species (Welcomme 1984). Another species which should be regarded with caution when being considered for introduction is the S. gairdneri. The introduction of S. gairdneri can be somewhat controversial, since this species has been associated with the spread of furunculosis. This disease is thought of 110 to be native only to S. gairdneri of western North America. After introductions of S. gairdneri, furunculosis became a serious problem in European brown trout. Now, this disease can be found in most places where salmonids are cultured (Welcomme 1984). S. gairdneri is also known to be a carrier of Myxosoma cerebalis (Hoffman and Schubert 1984), a virulent parasite, which can survive in extremely low temperatures. It remains as a threat even if the carrier is already frozen. A danger such as this would warrant even more care to prevent the spread of an unwanted parasite that may do much damage to local species.

Inadequate documentation The documentaticn of introductions, even of the successful ones, has general:ly not been satisfactory. However, solving this problem may not be as simple as it seems. Some naive aquaculturists may introduce a potentially harmful species, unaware of the ecological effects of such an action, while unscrupulous traders or businessmen may do the same, quite deliberately, even with full knowledge of the detrimental consequences. In either case, the proper authorities are usually left uninformed of the introduction and thus, an already difficult problem is compounded.

Ecologicalpact

Inadequate documentation, itself an already complex problem, leads to an even more serious problem - the inability to monitor the impact of unrecorded exotic species on the native ecosystems. The danger of this lack of information and knowledge is that some of the species introduced could actually assume dominant niches in the natural ecosystems which may, over time, prove detrimental. Although most, if not all,are maintained in very controlled environments, the number that may escape these environments would not be easy to trace. There are still other exotic species not discussed in this report, for lack of data, but which are strongly suspected to have caused damage to the populations of some indigenous fishes. Among these "controversial" exotics are Poecilia velafera, which has endangered the native species Rhyacichihys aspro and Mesopristes cancellatus, and Tricogasrer trichopterus, which has endangered Capoera semfascio1ata (see Table A.IIl). Sometimes, because of unmonitored or unrecorded introductions, the scientific names of some species which have been brought in could not even be determined. With all these unidentified exotic species coming in to Taiwan, the task of studying the ecological impact of these species becomes even more complicated for fisheries scientists and authorities. In Taiwan, the tilapias were introduced by research institutes. Fisheries and aquaculture scientists studied them carefully before disseminating them among the interested farmers. Screening and meticulously experimenting on these exotic species before releasing them for commercial culture have helped prevent environmental and other problems. It enabled the researchers to gather valuable information regarding the ecology of these species, and therefore also enabled them to provide the necessary instruction to the people interested in the culture of tilapia. 111

Conclusions The case of the tilapias and that of P. altivelis exemplify the usefulness of well controlled introductions. However, two or several favorable cases are not enough. The problem on the lack of information on exotic aquatic species in Taiwan still remains, and calls for a more determined effort to maintain a record of all introduced species through a centralized system. A more vigorouseducational campaign should be undertaken by agencies,both private and governmental, concerned with aquatic resources. Intensive research on introduced species should be conducted before their dissemination throughout the aquaculture industry. Quarantine procedures must be mademore efficient and must be implemented more effectively. Only in these ways may it be possible to start to minimize the incidence of illegal or unmonitored introductions and other related problems. The proper planning and implementation of exotic introductions are difficult to carry out successfully without cooperation among countries. Information must be shared and exchanged between and among nations and mutually beneficial agreements must be forged, suchas that established at the Convention on International Trade in Endangered Species of Wild Fauna and Flora, more popularly known as the "Washington Conventiont'. The workshopon exotic species organized by the Asian Fisheries Society in June of 1988 was a meaningful move to address the issue. It is hoped that this initiative will be followed up and continued by the same and other organizations.

Acknowledgement The authors thank the following people who, in one way or another, have helped in the preparation of this report: Mr. R. Lazo, Mr. C.Y. Liu, Ms. M. Carigma, Ms. F. Lucero, Mr. W.Y. Liu, Mr. T.A. Lee, Mr. C.S. Tzeng, Mr. T.C. Yu and Mr. H.C. Yang.

References

Bell, T.A. and D.V. Lightner. 1984. TERN virus: infectivity and pathogenicity studies in Penaeus .rtylirostris and Penaeus vannamei. Aquaculture 38: 185-194. Chen, T.P. 1976. Aquaculture practices in Taiwan. Fishing News Books Limited, Famham, Surrey, England. 161p. Hoffman, G.L. and G. Schubert. 1984. Some parasites of exotic fishes, p. 233-261. In W.R. Courteney, Jr. and J.R. Stauffer, Jr. (eds.) Distribution, biology, and management of exotic fishes. The Johns Hopkins University Press, Baltimore, U.S.A. Kuo, H. 1969. Notes on hybridization of tilapia. JCRR Fish. Ser. 8: 116-117. (In Chinese with English abstract?) Liao, IC. and N.H. Chao. 1983. Development of prawn culture and its related studies in Taiwan,p. 127-142. In G.L. Rogers, R. Day and A. Lim (eds.) Proceedings of the First International Conference on Warm Water Aquaculture-Crustacea. Office of Continuing Education, Brigham Young University, Hawaii Campus, Hawaii, U.S.A. Liao, IC. and T.P. Chen. 1983. Status and prospects of tilapia culture in Taiwan,p. 588-598. In L. Fishelson and Z. Yaron (eds.) Proceedings of the International Symposium on Tilapia in Aquaculture, 8-13 May 1983. Nazareth, Israel. Liao, IC., N.H. Chao and L.S. Hsieh. 1973. Preliminary report of the experiments on propagation of giant freshwater prawn, Macrobrachiwn rosenbergii in Taiwan. J. Fish. Soc. Taiwan 2(2): 48-58. McCann, J.A. 1984. Involvement of the American Fisheries Society with exotic species, p. 1-7. In W.R. Courtenay, Jr. and J.R. Stauffer, Jr. (eds.) Distribution, biology, and management of exotic fishes. The Johns Hopkins University Press, Baltimore, U.S.A. Welcomme, R.L. 1984. International transfers of inland fish species, p. 22-40. In W.R. Courtenay, Jr. and J.R. Stauffer, Jr. (eds.) Distribution, biology, and management of exotic fishes. The Johns Hopkins University Press, Baltimore, U.S.A. Table 1. Exotic species introduced into Taiwan. FINFISH Scientific Name Common Name AreaOrigin of Importation Date of Productionfor 1987* (t) CultureStatus

Gambusia affinis Topminnow North America 1920 - Popular; monocultured SalmoOreochrom,s gairdneri Mossambicus RainbowMozambique trout ulapia JapanIndonesia 19571944 See Table 2 949.0 limitsWidespreadCold expansion; water, supply mono- cultured Continued 0.Tilapia niloticus zulu NileRedbelly tilapia tilapia JapanSouth Africa 19661963 See Table 2 a hybridPopular,Unpopular with used 0. mos- to culture Pangasius sutchi Thailand catfish Thailand 1970 turedsambicusUnpopular, polycul- females 0.Clarias aureus batrachus BlueWalking Lilapia catfish IsraelThailand 19741972 See Table 2 ** ticusCrossedPopular female with to obtain 0. nib- Ictalurus punctatus Channel catfish U.S.A. mid ** all maleUnpopular offspring LeptobarbusAnguila anguilba hoevenii BarbEuropean or sultan eel Europe 19761970's - Culture discontinued - Megalobrama amblycephala Wu-changfish fish MainlandIndonesia China 1979 - breedUnpopular,Unpopular; mono-not easy and to u;,-,.,.,,t,,,.,,,.,.,, I.,.,,,d.,. I -,,,,I, ,,.4, A.-.,., 1970's polyculturedPnnn1r mnnociiltnred Table 1. Continued Used for genetic studies CultureStatus and crossbreeding

Used to obtain monosex progeny by hybridiza- tion

Used to add new species

Promising; monocul- tured

Experimental

Important culture species withe exporta- tion of fry; polycul- tured

Mass produced; poly- cultured

Important culture species with exporta- tion of fry; polycultured

Important culture species with exportation of fry; polycultured

Important culture species with exportation of fry; polycultured

Important culture Scientific Name Common Name AreaOrigin of Importation Date of Productionfor 1987* (t) 0.Oreochromr hornorwn sp. WamiRed tilapia tilapia PhilippinesCosta Rica 19811979 See Table 2 species with exportation T. rendalli Red breast of fry; polycultured Colossoma bidens Freshwatertilapia pompano SouthAmazonSouth America Africa 19861981 See Table 2 AristichthysSciaenops nobilis ocellatus BigheadRed drum carp ChinaMainlandU.S.A. 1987 - Carassius auralus Crucian carp Mainland China Mass produced; poly- and Japan 2,899.6 cultured CtenophaiyngodonCirrhina molitorella idellus GrassMud carp carp Mainland China 10,031.1 120.0 Continued MylopharyngodonHypophthalmichthys piceus molitrix SnailSilver carp carp Mainland China 9,89l.9*** Cyprinu.s carpio Common carp Japan 1950before 4,386.8 Table 1. Continued CultureStatus popular,ExperimentalMass monoculturedproduced; vesy

fourthmateProductionExperimental; in generation captivity reached will not

Major agricultural pest

Major agricultural pest

Not cultured

Commerciaily cultured

Commercially cultured

Popular; monocultured

Scientific Name Common Name AreaOrigin of Importation Date of Productionfor 1987* MacrobrachiwnCRUSTACEANS rosenbergii (t) Commercially cultured

Penaeus slylirostris * Estimates by the Taiwan Fisheries Bureau. Commercially cultured ** Total production for the three species of catfishThis is is the 101.2 total t. production for both bighead carp and silver carp. P. vannamei

P. brasiliensis

P. schmiltiMOLLUSCS Acha!inafidicaApullarius insularwn

LaminariajaponicaUndariaSEAWEEDS pinnati Ida

U. undariodes

RanaREPTILES catesbeiana Giant river

Blue shrimp AlligatorCaiman mississippiensis latirostrLr White leg shrimp

Red spoiled shrimp

Southern white shrimp

Giant Msican snail

Apple snail

Kelp or konbu

Wakame

Thailand frogAlligatorAmerican bull Panama Caiman Panama

Brazil

Brazil

JapanArgentina

Japan

Japan

Japan 1970

1979 - 1981

1981

1932

1979

1976

1981

1981 1,354.0

1924 Table 2. Record of tilapia introductions to Taiwan. Oreochromss mossambi cur Species Year1944 IndonesiaAreaOrigin of Introducer Assisted by by introduced Number 0. mossambicus 1946 Singapore Wu & Kuo 13 Tilapia zihii 1963 South Africa Tang 16 0. ,ulolicus 1966 Japan Yu lrnai 56 Purposes Extension and Ore0. aureiss ochromss sp. 1974 Israel & TsengLiao, Huang Pruginin 83 ofTo animal increase protein the supply Unsuccessful Cultural Status (Red tilapia) 1979 Philippines Chess,Liao, Huang, Chao, during WWII & Liu &jsg 30 0. mossambicushornorum Total production of tilapia for 1987 exceeds 100,000 t. 1981 Costa Rica Huang Yeh 456 0.mo,ysambjcus * Israeli strain. Filipino strain. 1981 SouthAfrica Liao &Schoonbee Clark 50 curiosityBrought backby 2 re-out of Widely spread 0.T. ruloticusrendalli 19841981 FranceSouth Africa ChaoLiao&Liao & ClarkSereneSchoonbee 690 25 0.massambicurO.aw-eur 1984 France ChaoLiao& Serene 170*4036** turning soldiers from SE. Asia

sistantducingTo be used hybridcold-re- in pro- resistant;Well spread hard because to polycuhure it is cold

toiisdIntroduced its hybridization large sizefor culture due mossambicussizeWell resulting accepted fromfemale especially a cross its with large 0. GeneticHybridization studies and crossedMaintainedWell with accepted 0. atniloticus Tungkangespecially female Marinewhen Lab.; progenyTo obtaincross breeding monosex Notnot ready ready for forextension extension

breedingTo be used studies in cross Not ready for extension

breedingTobeusedincross studies Notreadyforextension strainTomaintainnewTo add new species UnderhybndizationstudyNot ready for extension

strainTomaintainnewiin UnderhybridizationstudyUnderhybsidizationstudy 116

Annex I LIST OF AQUARIUM FISH INTRODUCED INTO TAIWAN Abudefdufoxyodon Botia lecontei Abudefdufstarcki Botia macracantha Abudefdufmelanopus Botia modesta Acanthophthalmus semicinctus Botia pulchripinnis Acanthopsis choirorhyncus Brachydanio albolineatus Acanthurus leucosternon Brachydanio nigrofasciatus Achirus errans Brachydanio rerio Adioryx spinosissimus Brachygobius xanthozona Aeoliscus strigatus Brycinus longipinnis Aluteres scripta Alestes taeniurus Calloplesiopa altinelis Ambassis lala Callochromis pleurospilus Amblydoras hancockii Capoeta tetrazona Amphiprion biaculeatus Carnegiella strigata Amphiprion clarkii Centropyge argi Amphiprionfrenatus (Brevoort) Centropyge bicolor Amphiprion ocellaris cuvier Centropygeferrugatus Amphiprion perideraion (Bleeker) Centropygefisheri Amp hiprion parasema Centropyge loriculus Amphiprion polymnus Centropyge multicolor Amphiprion sebae Centropyge nox Anoptichthysjordani Centropyge potteri Aphyocharax rubropinnis Cephalopholis urodlus Aphyocyprinus sp. Chaetodermis spinosissiums Aphyosemion australe Chaeron ephippiwn Aphyosemion bivittatzim Chaeton ocrofasciatus Aphyosemion calliurmahli Chaeton quaddimaculatus Aphyosemion sjoestsdti Chaeton rainfordi Aphyosemion arnoldi Chaeton reticulatus Apistogramma ramirezi Chaeton sp. Aplocheilus dayi Chaetodontoplus duboulayi Apogon macularus Chaetodontoplus mesoleucus Apogon orbiculatus Chalinochromis brichardi Apteronotus albifrons Chanda ranga Arapaima gigas Cheirodon axelrodi Arnoldichthys spilopterus Chelmo rostratus Aulonocara nyassae Chilodus purl ctatus Chiloscyllum colax Chrysiptera starki Bacantiocheilus melanopterus Cichiasoma salvini Badis badis Colisa chuna Balantiocheilus melanopterus Colisafasciatus Balistoides conspicillum Colisa labiosa Barbodesfasciatus Colisa lalia Barbus everetti Condylactis sp. Barbusfasciatus Corisfulis Barbus lateristriga Corydoras metae Barbus nigrofasciatus Corynopoma riisei Barbus schwanefeldi Cromileptes altivelis Barbus semfasciolatus varia Cynolebias bellouii Barbus tetrazona Cynotilapia afra Barbus titteya Gyp hotilapiafro ntosa Betta splendens Bodianus amthioides Bodinus loxozonus Daino malabaricus Botia horae Dascyllus aruanius

Continued 117

Annex I. Continued

Dascyllus melamurus Holacanthus isabelita Dascyllus resticulatus Holacanthus passer Dasyatis kuhlii Ho/acanthus tricolor Dendrochirus zebra Hymenocera sp. Diane,na longibarbis Hoiplolatilus purpureaus Diploprion bifascarum Hyphessobrycon callistus Distichodus lusosso (Callistus callistus) Distichodus sexfasciatus Hyphessobrycon callistyus rosaceus Hyphessobryconflammeus Hyphessobrycon herbertaxeirodi Ecsenius bicolor Hyphessobrycon heterorhabdus Eigenmanni virescens Hyphessobrycon innesi Enoplometopus occidentalis Hyphessobrycon pulchripinnis Epaizeorhynchus kallopterus Hyphessobrycon rubrostigma Epinephelus tauvina Hyphessobrycon scholzei Eretmodus cyanostictus Hypostomus sp. Esomus malayan Hypseleo iris compressa Euxiphipips sextriatus Euxiphipips nevarchus Euxiphipips xanthometopon Julidochromis transcriptus Julipocheromis transcriptus Flamneu sammara Krypropterus macrocephalus

Gasteropelecus levis Gasterosteus aculeatus Labeo bicolor Gate rin chaetodonides Labeo erythrurus Genicanthus larmark (Lacepede) Labeo frenatus Geophagus thayeri Labeo numensis Gobiodon specie Labeotropheus trewavasae Glymmistes sexlineatus Labroides dimidiatus Gnathonemus macro lepidotus Lactoria cornua Gnathonemus petersi Lamprologus co,npressicep Gymnocorymbus ternetzi Lamprologus leleupi Gyrinocheilus aymonieri Lebistes reticulatusi Lebrasoma reliferum Lepisosteus oculatus Ha/ic hoeres chrysus Lepomis megalotis Hapalochlaena maculosa Leporinusfasciatus Haplochromis desfontainesi Lienardellafasciata Haplochromis linni Lima scabra Helosrorna rudoiphi Lo vulpinos Helostoma iemmincki Loricariafilamentoa Hemigrammus gracilis Lutjanus sp. Hemigrammus ocellfer Hemigrammus pulcher Hemigrammus rho dpstomus Macro gnat hus aculeatus Hemiodus gracilus Macropodus opercularis Hemiodus semitaenitatus Maso literatus Hemitaurichthys polylepis Mastacembelus maculatus Hippocampus coronatus Mesogonistlus chaetodon Hippocampus keliggi Merynnis schreitmullerii Hippocampus specie Microlabichthys tukapascalus Holacanthus arc uatus Microp his smithi Ho/acanthus ciliaris Moenkhausia oligolepis Holacanthus clarionensis Mogurnda mogurnada mogurnd

Continued 118

Annex I. Continued

Mollienisia sphenops (latipinna) Pro gnathodes aculeatus Momadactylus argentens Pseudobalistisfuscus Monodactylus sebae Pseudotropheus sp. Muraena pardalis Pterois antennata Mylossorna duriventris Pterophyllum eimekei Pterophyllum hecker Purple chromis Nannostomus anomalus Pygolites diacanthus Nemaptereleoteris magnficus Nemateleotris specie Rasbora borapetensis Neosilurus ater Rasbora dorsiocellata Neopetrolisthes ohshimai Rasbora heterornorpha Notopterus chitala Rosbora maculata Rasbora trilineata Rhinomurena amboinensis Opistognathus aurifons Rhynchocinetes sp. Opistognathus whitehurstii Osphronemus goramy Osteochilus vittatus Scolcpsis sp. Osteochilus hasselti Scorpaenodes littoralis Osteoglossum bicirrhosum Selenotoca multifasciata Osteoglossumferreirai Serranus spilurus Oxymonacanthus Ion girostris Shaerichthys osphrornenoides Siganus vulpinus Spilotichthys picturatus Pamacanthus imperator Stenopus hispidus Pan gastus sutchi Symphysodon aquifasciata Pan que nigrolineatus Symphysodon discus Pantodon buchholz Synaphobranchus sp. Parambassis gulliveri Synchiropus splendidus Pelotropoma melanoleucus Syngnathus boversi Peocilabrycon aqratus Snodontis angelicus Phenaxorgammus interruptus Synodontis davidi Pholidichthys leucoraenia Pimelodus clarias Platax teira Tamichihys albonubes Platax pinnatus Telmatherina ladigesi Plecostomus punctatas Thayeria boehlki Poecilia latipinna Thayeria sanctaemariae Poecilobrycon aura tus Toxotes jaculator Poecilobrycon puctatas Trichogaster leeri Pogonoculius zebra Trichogaster trichopertus Polycentrus shomburgki Trichogasrer trichopertus (surnatranus) Polyodon spat hula Trichogaster microlepis Pomacanthus annularis Triportheus elongatu.s Pomacanthus arcuatus Tropheus duboisi Pomacanthus chrysurus Pomacanthus coeruleus Pomacanthus imparotor Uara amphiacanthoides Pomacanthus maculosus Pomacanthus paru Pomacanthus zonipec tus Xanthichthys species Premnas biaculeatus Xiphophorus hellerii Prevagor melanocephalus Xiphophorus maculatus Pristella riddlei Prochidodus amazonensis Prochidodus insignis Zebrasona veliferum Prochidodus taeniurus Zebrasoma scopas Exotic Aquatic Species in Thailand

TWESUKDI PIYAKARNCHANA Department of Marine Science Faculty of Science Chulalongkorn University Bangkok, Thailand

Piyakamchana, T. 1989. Exotic aquatic species in Thailand,p. 119-124. In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pub!. 3, 154p. Asian Fisheries Society, Manila, Philippines.

The first record of an exotic aquatic species in Thailand can be traced back to Ayudhaya period of aboutthe year 1691-1692. At present there are about 15 species of fishes which were introduced for aquaculturepurposes. Among them only a few are confirmed as reproducing in the natural habitats. The exotic species in the aquarium tradeon the contrary were reported to increase rapidly from 69 species in 1963 to about 92 in 1988. Only 3 fish diseases were recorded tocome from these exotic species. Records on the real impact to the natural ecosystem from the introduced speciesare scarce.

The introduction of exotic fish into Thailand dates backto the Ayudhaya Period probably around the years 1691-1692 (Amatayakul 1957). However,not until 1953, was a royal decree, which prohibited the introductions of many exotic species of animals andplants, proclaimed and implemented. The purposes of introducing exotic animals and plants into Thailandare at least three fold; for consumption, for aquaculture, and for home aquarium and exhibitionpurposes. The major countries from which these exotic animalsare exported into Thailand are Japan, Indonesia, Singapore, Sri Lanka, Taiwan, Hongkong, Philippines, Burma andThe United Kingdom. Some countries frequently actas middlemen. At present, the trading aquarium exotic species, especially fish, is very popular in Thailand.

Historical Background

There are three periods in which the exotic aquatic animalswere introduced into Thailand. The first period was before 1953 in which three species ofChinese carps, grass, bighead and silver carps were introduced, mostly by the Chinese immigrants, foraquaculture purposes. These fish carried parasites such as anchor worm (Lernaea sp.)cotton wool disease (Saprolegina sp.), and fish louse (Argulus sp.). These fish, in the latter dates,were widely spread all over the country, and the parasites and associated diseases spread with them. Thereare no reliable records on the degree of the destruction by these diseases to the native species. The second period was during 1953-1982. This period was basedon the time of the first proclamation of the Royal Decree called "The Prevention on the introduction of certain freshwater fishes, 1953."

119 120

This decree prohibited the introduction of cyprinids into the country without permission. It also required the introducer to present evidence that they were free from certain diseases. The third period is from 1983 to the present time. There was an amendment of the Royal Decree in 1982 and it was made law in 1983. The main reason for this amendment was to stop the wide outbreak of the so called "ulcerous fish diseases" in this country during 1983. The diseases which were found to be caused by certain viruses suspected to have been introduced through exotic aquarium fish. The decree which is still in use prohibited the introduction of aquatic organisms of freshwater and marine origin. They include the following:

Fish - 176 species.

Other aquatic animals (e.g., crabs, corals, molluscs and others) - 21 species.

Algae - 16 species.

Introductions

Aquarium Purposes A compilation of exotic aquarium species is given in Tables la and lb. Because of the insufficient records available from Government agencies and the private sector, information is not available on the dates and country of introduction, and it is impossible to complete the list and details of historical and the present status of most species. The first record on 1)0th local and introduced fish species was made by Chuensri (1963). Among these exotic fishes, the goldfish (Carassius auratus) is claimed to be the oldest. It had been introduced in Thailand (then called Siam) in 1692-1697, during the Audhaya Period (Amatayaku 1957). The second introductory period of the aquarium fishes started about 70 years ago. The Fisheries Department, Ministry of Agriculture and Cooperative,and the Ministry of Public Health, jointly introduced the mosquito eating fishes (Gambusia spp.), for malaria control. This species is now widely distributed in natural waters especially in the urban region of the big cities in Thailand. It is also recognized that of all exotic fishes, the cichlids are the most popular. The second priority are those of the Family Cyprinidae.

For Aquaculture Purposes

Of the 36 species of fishes cultured in Thailand, about 15 species are introduced, and are listed in Table 2. It could be dated back to the year 1912 when common carp, Cyprinus CarplO was introduced from China. The Chinese grass carp(Ctenopharyngodon idellus) and bighead (Aristichthys nobilis) were introduced by Chinese immigrants in 1932. At least two species e.g., trout (Salmo gairdneri) and Amago salmon (O,i.chorhynchus rhodurus) were introduced to Thailand for experimental purposes in the highland development project in the northern part of Thailand. 121

Present Status of the Exotic Species

The present status of the exotic species are classified at different levels. Those species that are used for aquaculture such as the two species of tilapias (Oreochromis mossambicus and 0. niloticus) are now well established in the ecosystem of Thailand. They are completely viable. 0. niloticus is more popular as food than the other. Common carp is also known to breed in natural waters. Among the three species of the Chinese carps, which are successfully grown in aquaculture systems, none of them breed naturally. Of the aquarium exotic species, few successfully breed naturally and the rest are bred artificially. In some species for example, a black tetra of black kamoor, (Gymnocorymbus terneizi) and a Jack Dempsey (Cichiosoma biocellatum) were first imported from South American countries (Paraguay, Bolivia and Argentina) and in 1950s reintroduced from Hongkong and Japan. They breed successfully in the natural habitats of Thailand.

Recorded Ecological Effects

Surprisingly, there are very few documented ecological effects by introduced species in Thailand. The author observed that 0. mossarnbicus is a nuisance species and even considered it as a bottom surface competitor to the brackish water shrimp e.g., Penaeus merguiensis, in culture ponds. A species of American freshwater crayfish (Procambrus clarkii) and a cherry snail, Ampularia gigas were suspected by some freshwater prawn culturists to be the cause of the stem damages of rice in the paddy fields. It was also suspected that the introductory American bull frog, (Rana catesbina) might be harmful to the local species of frogs (Ta Yoo 1986). Four exotic aquatic plants were reported by Santi (1986) and Tandaraporn (1962): Echimodorus peruensis or the Peruvian sword or black amazon sword, Cabomba caroliniana, Najas indica and Potamogeton crispus. These are also suspected to be competitors to local aquatic plants. Tandaraporn (1962), reported the possible effect on fishes of three species of aquatic plants, namely C. caroliniana, N. indica and P. crispus in helping to prolong the survival of 0. mossambicus. Of the exotics, introduced for aquaculture, the Chinese carps are reported to have been responsible for introduction and spread of some diseases (Kanthomthurapuch 1984).

Conclusions Three purposes are recognised as reason for introduction of fishes into Thailand; for consumption, for aquarium and for aquaculture (Tables 1 and 2). There are about 15 species of exotic fish that can be classified as being used in aquaculture. They have successfully survived and grow in natural waters and impoundments in Thailand. Only two species 0. mossambicus and 0. niloticus are capable of reproducing in reservoirs and in natural waters. It is also noticeable that the number of exotics of African origin has increased from 1963 to 1988. There were at least 19 species of African fishes in 1988, as compared to 6 species in 1963. The exotic species form the American continent (North, Central and South America) have also increased from 42 species in 1963 to 52 species in 1988 (Table 3). 122

It is also found that the exotic species for the aquarium fishes in Asia have decreased from 18 species in 1963 to only 15 species in 1988. The exotic marine fishes, mainly from the Philippines have increased from 2 species in 1963 to 5 species in 1988 (Table 3). Only a few species of the exotic aquarium fishes can breed successfully naturally in Thailand. It is also suspected that the cause of the decrease of the exotic species of aquarium fish from Asian countries might be either by the more restricted enforcement of the conservation laws or by the increasing deterioration of the natural habitats for these species in the respective countries. It is necessary for the countries in the region to cooperate in order to protect these most valuable resources.

References

Axelrod, H.R., W.E. Burgess, C.W. Emmens, N. Prones, J.G. Walls and R. Hunziker. 1987. Atlas of freshwater aquarium fishes. H.F.H. Publication, Inc. 992p. Amatayakul, C. 1957. Gold Fish. Thai Fisheries Gazette 10(2): 169. Cheunsri, C. 1963. The survey of the exotic aquarium fishes in Bangkok. Senior thesis for the B.S. degree, Faculty of Esheries, Kasetsart University, 99 p. Daungsawat, S. and T. Puphipat. 1982. Life history of exotic species. The Institute of the National Freshwater Fisheries, Report 7: 52p. Kanthomthurapoch P. 1984, Introducing of the life aquatic animals of Thailand. Thai Fisheries Gazette 3: 251-258. Pawapootanon, A. 1982. Fish stocking program in the Ubolratana Reservoir. Thai Fisheries Gazette 35(2): 205-2 13. Tandarapom, K. 1962. Use of aquatic plants for fish culture. Thai Fisheries Gazette 15(4): 419-426. Tayoo (Pen name). 1986. Kob Krating: Is it a real threat then? Thai Fisheries Gazette 13: 7-8. Santi (Pen name). 1986. Aquarium Tank Plant Decoration. Thai Fisheries Gazette 13: 12-15. 123

Table 1 a. Exotic fishes introduced to Thailand from North, Central and South America.

Taxonomic Status Common Name Introduced from Year Disease Original

Acestrorhnamchus hepsetes Argentina 1960 Aequidens rivulatu.s Riverlatus cichlid erun South America terro Aphyocharax robotropinis Bloodfish Argentina 1950 Apteronotus albifrons Black ghost Astronotus ocellatus Oscar, peacock eye cichlid Amazon, Paraguay White spot disease Astyanexfasciatusr albino silver tetra Central & South America Carnegiella marchae Black winged hatchet fish Orinoco, Amazon, Brazil 1957 C. strigata Marble hatchet fish Guiana, South Amazon Chiaroden axeirodi Cardinal tetra South America Cichiasoma bicellatwn Jack Dempsey Amazon 1950-56 C. citrinellum Red devil cichlid C. corydhaenoides Chocolate cichlid C. managuen Manguense cichlid Nicaragua, Central America 1983 C. meeki Fire mouth cichlid Yucatan C. nigrofasciatum Pink cichlid White spot disease C. severum South Texas C. cyanguttatwn Texas cichlid C. synspilum Firehead cichlid Corydoras aineu.s Bronze catfish C. haotatus Dwarf corydatus Amazon 1950 C. paleatus Peppered cory Argentina, Brazil Gambusia affinis Gymnocorymobus lerneizi Black tetra, Black Kamoor Paraguay, Argentina 1950 Gastropelacus leviz Silver hatchet fish Brazil 1956 G. sternicla common hatchet fish Venezuela Hemigrammus ocelliler head and tail light Amazon, Brazil, Guiana H. puicher Pretty tetra Amazon, Peru 1960 H. rhodostomu.s Ilyphessobryconflammesss Flame tetra, Red tetra Rio de Janeiro 1950 H. innesi Neon tetra Upper Amazon 1953 Hypostomus plecostomu.s Sucker catfish Lebistes reticulatus Guppy, Rainbowfish Trinidad, Venezuela Lepisosteu.s oculatu.s Gar pike or spotted Gar pike North America Molliensia velfera Giant Sailfin molly Yucatan Moenkhausia sahctaefilominae Moenkhausia M. digolepis Glass tetra Brazil 1957 Namnostomus aripirangensis Brown pencil fish Amazon N. anomalu.s steindachner Osteoglossum bicirrhoswn arozena Guiana, Amazon 1959 Phraetocephalus hemlliupteru.s Red tailed catfish Paecilia reticulata Guppy, million fish Poecilo brycon unifasciatus one-tailed pencilfish 1959 Poecilia latipinna Sailfish molly Mexico, Texas, Florida, Virginia Pseudoptatystomafasciatwn tiger shovelnosed catfish Amazon Pristelta riddui Pristella x-ray fish North of SA, Guiana 1950 Pterophyllwn scalar Angelfish Guiana Thaveria bochlkei T. obliques South America Tilapia buttikoferi Hornet tilapia cichlid Xiphophorus maculatus Red platy Guatemala, Honduras 124

Table lb. Exotic fishes introduced to Thailand from Africa, Asia and Australia.

Taxonomic Status Ccinmon Name Introduced from Year Disease Original

Po/ypterus deihezi Delnezi's biebir Middle of Congo river, Africa Monodactylus arrgenteus and Mono, Malayan Angle, East Africa, Note: Marine M. sebae, M.falciformis Fingerfish Malaysia. Borneo Labidochromsr exasperatus Likoma pearl cichlid Common in Malawi, Lake Tanganyika, Africa Hepsetas odoe African pika characin Central Africa Tetraodon miurus Red Puffer, Congo puffer Africa, Congo River Note: M:arine Hapiocronsis polystigma Polyatigma cichlid, Polly cichlid Distighodas sexfasgiasus dow terra, Six-barred Africa, Congo river distichodus Brachydania redo Zebra danio Western India Amphiprionfrenatu.s Tomato crown fish Phillipines Note: Marine Acanthurus leucosleron Powder blue surgeon Indo-pacific to Red Sea. Note: Marine Et ropi us rnaculatur Orange chromide cichild Sri Lanka and part of India Barbus, sach.ri Gold-fmned bath, Singapore. Malaysia Sach's barb Barbus titteya Cheny bath Sri Lanka. Asia Luciocephaiu,r puicher Pike-head Malaysia, Sumatra, Sends Islands, Borneo Pesudochronsis paccanella Paccaneila Indonesia Note: Marine Porno centhres semicircvjasus Blue koran Phillipines Note: Marine Tanichthyzs albonubes White doud, mountain minnow China Micralesles interrupt us Congo tetra Zaire, Africa Phenacogramnsus interrupt us Hap! ochrornis senustus Victoria Lake Aulonocara nyashsa Malawi- blue Malawi Lake Heterosis ,siloticus African arovana River Nile, Africa Scieropages fordmi Australian arovana New Guinea Halaptearus elecirictes Electric catfish Central Africa Platax orbics.Jaria Bat fish Philhipines Note: Marine Melanochromis auraS us Auratus cichlid, Malawi Golden cieblid Malswi Lake, Africa Distichodus lusosso Long nosed clown tetra Congo river, Africa Hap!ochrorni.r moorii Blue dolphin, Sri Lanka, India, Asia Blue lumphead Etroplus maculalus Orange chromid cichlid Sri Lanka, India, Asia Aulonocara nyassae Yellow Malawi, Malawi Lake, Africa Malawi Gold Gnaihomus pet ersi Elephant nose Central Africa Hap! ochrornis callipterus Callipterus cichlid Malawi Lake, Africa Mormyras nigricans Mormyrid Africa Pee udot ropheus iropheus Tropheops cichlid, Malawi Lake, Africa Black dorsal fin

Table 2. Live fish species which were introduced to Thailand for aquaculture Table 3. Comparison of the exotic species for aquarium fishes in 1963 and and for scientific research. 1988.

1988 Scientific Name Introduced From Origin 1963 Asia 18 Species 15 Species Oreochrorner ,nossarnbi cur 1949 Malaysia Africa T. melanopleura 1955 Belgium 6 Species 19 Species O.rsi!oticus 1965 Japan Australia I Species 1 Species 0. aareue 1970 Israel America North, Cyprissuscarpio 1912 China Central & South 42 Species 52 Species 5 Species Hypophthalmichthys molitrix 1932 China Marine 2 Speciea Cienopharyngodon (della 1932 China Ari.rtichthys nobilis 1932 China Total 69 Species 92 Species Labeo rohita 1968 India Cotta cotla 1979 Bangladesh Caraxrirsr caro.ssius 1980 Japan Cirrhin,sa inrigala 1980 Japan Angaillafaponica 1973 Japan Salmo gairdneri 1973 Canada Onchorhyncris rlrodorus 1981 Japan

(Source: Daungsawat and Phupipat 1982) Australian Government Position: Introduction of Exotic Aquatic Species

FRANCES B. MICHAELIS Australian National Parks and Wildlife Service GPO Box 636 Canberra, ACT 2601

Michaelis, F.B. 1989. Australian government position: introduction of exotic aquatic species, p. 125-132. In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pub!. 3, 154 p. Asian Fisheries Society, Manila, Philippines.

The impact of introduced aquatic species on native species in Australia is considered. In addition the role of the Commonwealth Government and other statutory agencies in the protection of the Australian native flora and fauna is discussed. The mechanisms that regulate importation of live animals and plants into Australia are briefly presented. Australian obligations enacting international conventions for the protection of flora and fauna, and future directions in conservation are dealt with. In Australia the impact of introduced aquatic species on native species and their habitats has been considerable. About 22 species of freshwater fish, numerous aquatic invertebrates and 15 species of undesirable aquatic weeds have been mtroduced. There is an awareness of the need for State and Commonwealth legislation to protect native aquatic species and their habitats within Australia. The most important Commonwealth legislation to protect aquatic fauna is the Wildlife Protection (Regulation of Exports and imports) Act, 1982 which protects endangered wildlife and wildlife that would be threatened by continued unregulated trade. The Act seeks to prevent the introduction of live plants and animals that could adversely affect the Australian natural environment. The Act is administered by ANPWS, with technical advice in aquatic matters from the Advisory Committee on Live Fish (ACOLF) of the Australian Fisheries Council. At present, a few hundred species are permitted imports under Schedule 4 (freshwater fish) and Schedule 6 (marine aquarium fish). The Convention of Conservation of Nature in the South Pacific (Apia Convention) and the Convention for the Protection of the Natural Resources and Environment of the South Pacific (SPREP Convention ) are outlined to p"vide models that might be considered by the Asian nations for regional co-operation in environmental conservation.

In Australia, the impact of introduced aquatic species on native species and their habitats has been considerable. The following have been introduced:

about 22 species of freshwater fish (McKay, present volume) eight marine and estuarine (including anadromous) fish (Pollard and Hutchings, pers. comm.) numerous aquatic invertebrates 15 species of undesirable aquatic weeds (Arthington and Mitchell 1986) and at least eight species of marine algae (Pollard and Hutchings, pers. comm.).

There is an awareness of the need for State and Commonwealth legislation to protect native aquatic species and their habitats in Australia. The present paper addresses ways in which Commonwealth Legislation protects native aquatic species.

125 126

The Role of the Commonwealth Government In Australia, responsibility for management of native fauna is vested with each State and Territory Government. The Commonwealth (Federal) Government has responsibilities for fauna in Commonwealth Territories, as well as for matters relating to fauna in import and export control, foreign affairs and foreign trade. Responsibility for fisheries management rests with the State and Territory Governments except for the above mentioned matters. In 1976, the Endangered Species Regulations were promulgated under the Customs Act 1901. This legislation remained in force until1 May 1984 when the Wildlife Protection (Regulation of Exports and Imports) Act 1982 came into effect. In the matter of import and export control of fish (excluding fish products'), the most important Commonwealth legislation is the Wildlife Protection (Regulation of Exports and Imports) Act 1982. This Act protects endangered wildlife and wildlife that would be threatened by continuation of unregulated trade (Schedules 1 and 2), generally precludes export of live Australian fauna for commercial purposes, and seeks to prevent introduction of live plants and animals that could adversely affect the Australian natural environment (Schedules 5 and 6). Schedule 6 contains a listing of aquarium fish, both freshwater and marire that are 'permitted imports'. Schedules to the Act are regularly amended. With the commencement of the Act, all previous controls were consolidated into a single piece of legislation and responsibility for administration was placed with the Australian National Parks and Wildlife Service (ANPWS). Under the Act, the export and import of wildlife (and wildlife products) which is threatened with extinction or considered endangered is strictly regulated. Permits for trade in such wildlife are provided where certain conditionsprevail, and the trade is for scientific or bona fide zoological purposes, or the wildlife has been bred in captivity or artificially propagated. Importation of species, such as aquarium fish, which could threaten the survival of wildlife within Australia is also subject to control. Intending importers should write to the Director, ANPWS, GPO Box 636, Canberra, ACT 2601 Australia and complete a proforma outlining distribution, ecology and potential of the species to establish feral populations. All applications are considered by the Advisory Committee on Live Fish (ACOLF) to the Standing Committee of the Australian Fisheries Council. This technical advisory committee includes Commonwealth Government (ANPWS, Australian Quarantine Inspection Service (AQIS)), State and Territory Fisheries Authorities (8 members), an expert on fish disease and an expert on aquarium fish and meets twice a year. Criteria used by ACOLF in assessing applications are attached (Appendix III); the emphasis being on the potential of the species to survive and disperse in the wild. The export of Australian wildlife requires a permit unless exempted by the Act. Export of live Australian animals is only permitted for scientific or bona fide zoological purposes, or as household pets, in which case there are stringent requirements which must be met.

The Role of ANPWS in Administration

ANPWS has, since proclamation of the Wildlife Protection Act, been endeavouring to strengthen and develop close liaison with all Australian Conservation agencies and with all Federal departments which have a relationship to the control of wildlife. 127

There are presently eight State or Territory Wildlife agencies in Australia. Each operates independently and exercises control and enforcement of wildlife matters under separate pieces of legislation. Such legislation regulate the trade, holding of, and movement of wildlife both within and between Australian States and Territories. Law enforcement is conducted at the State and Territory level by officers of each conservation Service and is supported by Statelferritory police forces. Such legislation is not considered further in this paper. The international movement of fauna and flora is a Federal responsibility and, dependent upon the commodity, is administered by a variety of departments, e.g., with regard to fish:

Trade in fish products - Australian Fisheries Service, Department of Primary Industries and Energy;

Import and Export of fish - Australian National Parks and Wildlife Service, Australian Quarantine and Inspection Service (AQIS).

At the Federal level, enforcement is primarily the responsibility of the Australian Federal Police and the Australian Customs Service. In September 1985, ANPWS hosted the first national seminar on wildlife law enforcement, which was conducted in Canberra. The seminar was designed to encourage wide-ranging discussions on enforcement matters (regardless of State or Federal requirements). Similar seminars have been held in Canberra, October 1986 and in Adelaide, April 1988, on the theme of intelligence gathering. As a result of the above seminars, a number of prosecutions were initiated at both the State and Federal level. ANPWS has been dealing with a number of Convention on International Trade in Endangered Species (CITES) countries particularly USA, West Germany, South Africa and Denmark, on enforcement matters.

The Role of ANPWS in Research

The aim of the ANPWS Research and Survey Program is to facilitate the production of reliable scientific and socio-economic information for the formulation and implementation of nature conservation policies and management programs. Priority information needs are periodically reviewed and the scope of the program is revised accordingly. The Research and Survey Program comprises a suite of projects funded on the basis of contracted consultancy services. Projects on exotic fish are listed at Appendix I and the full titles of the Reports are given in the references. A recent survey of the introduced Tilapia, in the Cairns region of North Queensland (Lear 1987) suggested that they have set up populations up to 3 km from point of release over a period of 5 years, and will eventually become common in wetlands in the Cairns city area. The means of dispersal, whether by nature or man, could not be determined. 128

The International Obligations of Australia

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) is probably the most important international agreement protecting endangered species of plants and animals. The governments of ninety three countries, including Australia, have now signed CITES. Through CITES, these countries are trying to establish a worldwide network of controlson trade in endangered species and species that could become endangered. Within the member countries of CITES, Australia stands to the fore in providing protection of its native animals and plants, in particular those that are endangered. The Convention on Wetlands of International Importance Especially as Waterfowl Habitat (Ramsar Convention) aims to promote the conservation of wetlands and waterfowl, to establish nature reserves on wetlands and provide adequately for their protection and wardening and to promote training of personnel competent in the fields of wetlands research, management and wardening. In addition, it aims to increase, through management, waterfowl populations on appropriate wetlands. Australia signed the Convention without reservation as to ratification in 1974 and became the first country to do so. The agreement came into force internationally on 21 December 1975. Regulations to implement this Convention in Australia were not needed since the Convention imposes responsibilities which may be met either administratively or by action under existing legislation. A Working Group of the Council of Nature Conservation Ministers (CONCC)M) has been established to advise on the implementation of the Ramsar Convention. CONCC)M has agreed that the nomination of wetlands to the List of Wetlands of International Importance is the responsibility of the individual States and the Northern Territory. The Australian National Parks and Wildlife Service, which is the principal advisor to the Commonwealth Government on national nature conservation and wildlife policies, provides the Convenor for the Working Group and co-ordinates activities under the Convention, including submission of nominations for wetlands to be added to the list (Appendix II) and the preparation of the national reports. There are two international conventions in which Australia has an interest that serve as models for regional co-operation in environmental conservation. Although there are some important differences, the two can be seen as complimentary.

The Convention on Conservation of Nature in the South PacWc (Apia Convention) was adopted in 1976 but has not yet entered into force. Australia intends to accede to the Convention, which aims to take action for the conservation, utilization and development of the natural resources of the South Pacific Region. Article V, paragraph 4states"Each contractingpartyshallcarefully consider the consequences of thedeliberate introduction into ecosystems of species which have not previously occurred therein".

The Convention for the Protection of the Natural Resources and Environment of the South Pacific Region (SPREP Convention) is not yet in force. Australlia signed the Convention in 1987 but has not yet ratified it. Article 14 is concerned with Specifically Protected Areas and the Protection of Wild Flora and Fauna. It aims to "preserve depleted, threatened or endangered flora and fauna...prohibit or 129

regulate any activity likely to have adverse affects on the species, ecosystems or biological processes that such (protected) areas are designed to protect".

Possible Future Directions

Future directions may involve new legislation, a threatened species initiative and further education. The new legislation would be helpful if it provided uniformity between States, Territories and the Commonwealth to define fish species that may be imported, translocated, released, etc. Commonwealth Government activities already protect threatened species and their habitats by the provision of research funds, provision of funds to States for purchase of property, management ofthreatenedspeciesinareasunder Commonwealthcontrol,and the implementation of obligations under international treaties. The Commonwealth Government has established an Endangered Species Advisory Committee to advise the Minister for the Arts, Sport, the Environment, Tourism and Territories on strategies, priorities and implementation of the endangered species program. The Government is also moving to create within the Australian National Parks and Wildlife Service (ANPWS) an Endangered Species Unit which will establish programs for conservation of endangered wildlife in co-operation with State agencies. There is an urgent need for programs to inform the public about native aquatic invertebrates and fish, and to make people aware of the dangers of exotic fish and invertebrate introductions.

Relevant Literature

Anon. 1976. Convention on Conservation of Nature in the South Pacific. Apia, 12 June 1976. Anon. 1982. Wildlife protection (Regulation of Exports and Imports) Act 1982. Australian Government Publishing Service. No. 149 of 1982. Arthington, A.H. and D. Milton. 1983. Ecology and interaction of exotic and endemic freshwater fishes in South Eastern Queensland streams. Consultancy Report prepared for Australian National Parks and Wildlife Service, Canberra, Australia. 403 p. Arthington, A.H. and D. Mitchell. 1986. Aquatic Invading Species, p. 34-53. In R.H. Groves and JJ. Burdon (eds.) Ecology of Biological Invasions: An Australian Perspective. Australian Academy of Science, Canberra. Lear, R.J. 1987. Survey of introduced Tilapia in the Cairns Region, North Queensland. Consultancy Report prepared for Australian National Parks and Wildlife Service, Canberra. Australia. XX p. McKay, RJ. 1978. The Exotic freshwater fishes of Queensland. Consultancy Report prepared for Australian National Parks and Wildlife Service, Canberra, Australia. 103 p. McKay, R.J. Present volume. Michaelis, F.B. 1985. Threatened Fish. Report on threatened fishininland waters in Australia. Australian National Parks and Wildlife Service. Report No. 3: 45 p. Michaelis, F.B. 1986. Conservation of Australian aquatic fauna, p. 599-613. In P. De Deckker, and W.D. Williams (eds.). Limnology in Australia. CSIRO Australia, Melbourne and Dr. W. Junk Publishers, Dordrecht. Mitchell, D.S. 1986. Aquatic macrophytes and man, p. 587-598. In P. De Deckker and W.D. Williams (eds.). Limnology in Australia. CSIRO Australia, Melbourne and Dr. W. Junk Publishers, Dordrecht. UNEP. 1987. Convention for the Protection of the Natural Resources and Environment of the South Pacific Region, Regional Seas, UNEP. 130 APPENDIX I

Australian National Parks and Wildlife Service Research and Surveys Program Exotic Fish

Year Project Investigator

1976177 A survey of alien freshwater Mr. R.J. McKay, fish in the Moreton Bay Region Queensland Museum

1977178 A survey of alien freshwater fish Mr. R.J. McKay, in Queensland coastal streams Queensland Museum

1980/81 Ecology and interaction of Exotic Dr. A. Arthington, 1982/83 and Endemic Freshwater fishes in Griffith University South-eastern Queensland streams

1984/85 Marine Aquarium Fish - permitted Ms P. Kailola, imports for aquarium purposes Adelaide

1986/87 Investigation of Spread of Tilapia Mr. R. Lear, Cairns, Sarotherodon spp. inCairns! Queensland Townsville Region

APPENDIX II

Wetlands Designated by Australia to the List of Wetlands of International Importance

Name State or Location Area (ha) Territory

Cobourg Peninsula, N.T. 11022'S, 191,660 Aboriginal Land and 131046' - Wildlife Sanctuary 132°35'E Kakadu National N.T. 12005' - 667,000 Park, Stage I 13 030'S, 131022' - l33000'E Moulting Lagoon Tas. 42005'S, l48°lO'E 3,930 Logan Lagoon Tas. 40010'S, 2,320 Conservation Area 1480 l7'E Sea Elephant Tas. 39045'S, 1,730 Conservation Area l44°05'E Pittwater - Tas. 42047'S, 2,920 Orielton Lagoon l47°30'E Apsley Marshes Tas. 4 1056'S, 940 l48°12'E East Coast Cape Tag. 40018' - 4,230 Barren Island 40026'S, Lagoons 148020' 148°26'E Flood Plain Lower Tas. 41054'S, 1,650 Ringaroorna River 147°56'E Jocks Lagoon Tas. 41021'S, 70 148°18'E Northwestern Tas. 42090'S, 270 Corner of Lake Crescent l47°l0'E Little Waterhouse Tag. 40052'S, 90 Lake 147°37'E Corner Inlet Vic. 38036' 51,500 38055'S, 146011' - 146°53'E Continued 131 Appendix II. Continued

Name State or Location Area (ha) Tethtory

Barmah Forest, Vic. 35050' - 28,500 36001'S, 144°56' - 145°20'E Gunbower Forest Vic. 35039' - 19,450 36000'S, 144008' - I 44°30'E Hattah-Kulkyne Vic. 34°38' - 1,018 Lakes 34045'5, 142023' - 142°29'E Kerang Wetlands Vic. 35030' - 9,172 35050'S, 143042' - 144°10'E Port Phillip Bay Vic. 37053' - 7,000 (Western Shoreline) and 38015'S, Bellarine Peninsula 144024' - 144°48'E Western Port Vic. 38012' - 52,325 3 803 1'S, 145002' - 145°32'E Western District Vic. 38000' - 30,182 Lakes 38020'S, 143007' - 143°55'E Gippsland Lakes Vic. 37049' - 43,046 3 8012'S, 147004' - 148008'E Lake Albacutya Vie. 35046'S, 10,700 141°58'E Towra Point Nature NSW 34000'S, 281 Reserve 151010'E Kooragang Nature NSW 32051'S, 2,206 Reserve 151°46'E Coorong and Lakes SA 35018' - 140,500 Alexandrina and Albert 36033'S, 138046' - 139°50'E Boo! and Hacks SA 37006' - 3,200 Lagoons 31010'S, 140039' - 140°44'E Macquarie Marshes NSW 30045'S, 18,200 Nature Reserve 147°33'E Coongie Lakes SA 28°36' - 1,980,000 26018'S, 139000' - 141 000'E 'Riverland SA 3401!' - 30,600 26018'S, 140042' - !41000'E

Total Area 3,304,690 132

APPENDIX LII

Criteria for Permitted Importation of Aquarium Fish

ADVISORY COMMITTEE ON LIVE FISH (ACOLF) to the Standing Committee of the Australian Fisheries Council

Evaluation of fish species for exclusion from the list of permitted aquarium fish imposts should take into consideration the following points:

Any histosy of forming feral populations elsewhere or of having caused a significant problem elsewhere.

The capacity for survival and dispersal within Australia, particularly in combination with other undesirable characteristics.

Any likelihood of having a significant detrimental impact on other fish species or wildlife, or on the aquatic environment.

The status of the species as a known carrier of a dtsease not yet found in Australia,

The ability of the species to cause injury to man, livestock, wildlife or the environment (e.g., possessing spines, electric organs, toxins).

The potential for growth to a large size, particularly in species likely to be attractive under Australian conditions for aquaculture, sportfish stocking, weed control or similar activities not connected with the aquarium hobby.

The degree of difficulty in distinguishing the species from other (undesirable) species. ("Look-alikes").

In addition, for marine aquarium fish, the ability of the'species to establish in estuaries or migrate into freshwaters.

The availability of reliable biological information. Recommendations of the Workshop

1.0 TERMINOLOGY:

1.1 It was apparent that the terminology needed careful consideration, in spite of the issue of exotics and or introductions having been dealt with from timeto time. The matter was more complicated inthe region because zoogeographical boundaries and country boundaries in most cases werevery different from one another.

1.2 A separate sub-committee was appointed to examine andreport on suitable definitions for an exotic introduction, transplant and introduction. The committee could not come-up with acceptable definitions during the workshop and the workshop requested Dr. Chua Thia-Eng and Mr. Jay Maclean tosurvey the available literature and submit suitable definitions for consideration by the Committee on Exotics.

2.0 DATA BASE:

2.1 A considerable amount of fresh data was presented on the introduction of exotics into the region at the meeting. Some of the information however, neededto be revised by participants and the Chairman of the Exotics Group (Dr. S.S. De S) will coordinate this activity and standardize the presentation of the data.

2.2 The Chairman will also attempt to obtain comparable data from those countries which were not represented at the Workshop, and if possible also makeattempts to dig into the "grey literature" to find the same.

In order to achieve this end it might be necessary to identify and liaise with scientists who are interested in the topic in each of the countries in the region.

2.3 The Workshop took into account the interests and experience of the FAQ, EIFAC and the American Fisheries Society on this topic and the need for the Societyto liaise with these organizations was noted.

3.0 NEW INTRODUCTIONS:

3.1 The information available on the procedures adopted in making or decidingupon an introduction was scanty, except perhaps in Australia. Japan for example has no restrictions on live aquatic introductions.

3.2 As such, it was deemed appropriate and relevant to document the information available with respect to each country. The delegates were requested to furnish this information, in a schematic form, in due course. The Committee on Exotics will attempt to compile this information in a publishable form.

133 134

4.0 AQUARIUM FISH:

4.1 The delegates expressed concern over the growing aquarium fish trade which in most instances is responsible for introduction and spread of diseases.

4.2 The meeting agreed that an attempt should be made to list the common aquarium fish species imported/exported into from each country in the region, with notes on the quarantine measures adopted. All delegates were of the view that this is a very difficult task to achieve and would take a considerable amount of time to prepare an accurate list.

4.3 Instances in which a fish such as pirranha imported for the aquarium industry in Thailand has been discovered in the natural waters, were cited as examples of the need to address the issue in greater depth.

5.0 IMPACT OF INTRODUCTIONS:

5.1 It was agreed that most introductions, especially the food fish species, have had considerable socio-economic impact in most countries, in the region. It was also recognized that unlike in Europe, North America or for that matter, Australia, the assessment of the impact in most Asian countries should be made from. adifferent view point. As an initial step, five criteria were agreed upon to dei:ermine the impact of introduced, common food fish species, such as for example i;he tilapias, carps, etc. into each of the countries.

The final assessment is to be published in the Proceedings of this Workshop.

5.2 It was also felt that Asia has suffered few losses of native species upi:o now and the number endangered are also small as a result of introductions. However, this was no matter for complacency and the need to scrutinize the newproposals for introductions was accepted.

6.0 FUTURE ACTION:

6.1 It was agreed that the results of this Workshop should be published as an Asian Fisheries Society Publication. The publication would include the revised, presented papers and further data which the participants were asked to furnish and summary tables on a regional basis.

6.2 A standing committee of the Society on 'Exotics' consisting of

Prof. Sena S. De Silva (Chairman)

Dr. Frances Michaelis (Australia)

Dr. M. Shariff (Malaysia) 135

(two more to be co-opted) was appointed. This Committee will liaise with other organizations and countries, explore ways of addressing the issue of exotics in depth, and collect and synthesize data on exotics to provide relevant and useful information to Governments in the region when and if needed. List of Participants

Dr. Angela H. Arthington, Division of Australian Environmental Studies, Griffith University, Nathan, Queensland 4111, AUSTRALIA

Mr. Don Buckmaster, Fisheries Division, Department ofConservation Forests and Land, Arthur Rylan Institute, 123, Brown Street, Heiderberg, Victoria 3084, AUSTRALIA Dr. Kenji Chiba, Fisheries Lab, The University of Tokyo, Maisak, Hamana, Shizuaka, 431-02 JAPAN

Dr. F. Brian Davy, IDRC, Tanglin P.O. Box 101, SINGAPORE 9124

Prof. Sena S. De Silva, Department of Fisheries Biology, University of Ruhuna, Matara, SRI LANKA Dr. Chua Thia-Eng, do ICLARM, MC P0 Box 1501, Makati, Metro Manila, PHILIPPINES Dr. H. Muhammad Eidman, Faculty of Fisheries, Bogor Agricultural University, Darmaga Campus, Bogor, INDONESIA

Mr. Darryl Grey, Department of Industries and Development, GPO Box 4160, Darwin NT 5794, AUSTRALIA

Dr. John D. Humphrey, Australian Fish Health Reference Laboratory, P0 Box 388, Bendila, Victoria 3672, AUSTRALIA

Dr. Rogelio 0. Juliano, University of the Phillipines in the Visayas, Iloilo City, PHILIPPINES

Dr. Akio Kanazawa, Faculty of Fisheries, Kagoshima University., 4-58-20 Shimoarata, Kagoshima, JAPAN Ms. Henen K. Lasson, Northern Territory Museum, P.O. Box 4646, Darwin, N.T. 5794, AUSTRALIA

Dr. I. Chiu Liao, Taiwan Fisheries Research Institute, 199 Hou - Ih Rd. Keelung, TAIWAN Dr. Hsi-Chuang Liu, Institute of Oceanography, College of Science, National Taiwan University, Taipei, TAIWAN

136 137

Mr. J. Maclean, do ICLARM, MC P0 Box 1501, Makati, Metro Manila, PHIILIPPINES

Dr. Frances Michaelis, ANPWS, GPO Box 636, Canberra, Act 2601, AUSTRALIA

Mr. Michael Peani, cl- Department of Industries and Development, GPO Box 4160, Darwin, N.T. 5794, AUSTRALIA

Dr. Twesukdi Piyakarncha, Dept. of Marine Science, Faculty of Science, Chulalongkorn University, Bangkok 10500, THAILAND

Prof. Meng Quing-Wen, Shanghai Fisheries University, 334, Jun Gong Road, Shanghai, CHTNA

Dr.David Ramm,Fisheries Division,Dept.ofIndustriesand Development, GPO Box 4160, Darwin, N.T. 5794, AUSTRALIA

Prof. H.P.C. Shetty, Director of Instruction (Fisheries), University of Agricultural Sciences, College of Fisheries, Mangalore 575002, INDIA 138

APPENDICES

On the basis of the specific recommendation made by the Workshops attempts were made to gather additional information regarding introductions made in those Asian countries that were not represented,compile a list of aquarium fish introduced into each country, and assess the impact of major food fish species introductions. Needless to say that all the objectives set out could not be fully realized at the time the Proceeding went for print. Contacts were made with scientists in Bangladesh, Burma, Cambodia, Laos, Nepal and Vietnam amongst others; not all of them however, have responded. In spite of these limitations some of the information is included as it is hoped that this will provide the base for a more comprehensive documentation at a later date. The appendices that follow are therefore, not strictly a part of the Proceedings but are components of the follow-up activities adopted by the Workshop. Appendix I

Definitions of Exotics

The1986ASFA Thesaurus gives a "scope note" or "rough definition" of introduced species as "Establishment in a new geographical area of a species by migration or artificial transportation." The same Thesaurus gives a "rough definition" of transplantationas "Artificial" introduction of organisms into habitats where they do not occur naturally. The ASFA Thesaurus does not use the word exotic. Welcomme, R.L.1988.(International introductions of inland aquatic species. FAO Tech. Pap.294, 318 p.)follows the1987EIFAC Code of Practice, which used these definitions. Introduced species (includes both non-indigenous and exotic species): Any species intentionally or accidentally transported and released by man into an environment outside its present range.

Transferred species (includes transplantedspecies): Any species intentionally or accidentally transported and released within its present range.

"Transfers are usually intended to support stressed populations, introduce genetic diversity into a stock or to reestablish a species whose stocks have failed locally. Introductions are intended to insert a totally new element into the fauna".

Welcomme commented, "One reservation is made with respect to these definitions in thata species is considered to have been introduced to a country once it has crossed national boundaries. This means that species are included in the listing if they are transported intoa country as part of current commercial practice for food or ornament and not for stocking into natural environments. Experience has shown that even such species may have impacts through the release of pathogens or through escape."

Marine species: Any aquatic species that does not spend its entire life cycle in fresh water.

Introduced species (= non-indigenous species; includes both non-indigenous and exotic species): Any species intentionally or accidentally transported and released byman into an environment outside its present range.

Transferred species (= transplanted species): Any species intentionally or accidentally transported and released within its present range.

Quarantined species: Any species held in a confined or enclosed system that is designed to prevent any possibility of the release of the species, or any of its diseases or any other associated organisms into the environment.

139 140

In the article "Strategies for reducing risk from introductions of aquatic organisms" by C.C. Kohler (Fisheries 11(2): 2-3 (1986)), the definitions used, which were those of Shafland, P.L. and W.M. Lewis 1984 (Terminology associated with introduced organisms. Fisheries 9(4): 17- 18), were explained thus:

For the present purposes, the terminology associated with introduced organisms follows that of Shafland and Lewis (1984). They define introduced as a plant or animal moved from one place to another by man (i.e., an individual, group, or population cr organisms that occur in a particular locale due to man's actions). They define exotic as an organism introduced from a foreign country (i.e., one whose entire range is outside the country where found), and a transplant as an organism moved outside its native range but within a country where it occurs naturally (i.e., one whose native range includes at least a portion of the country where found). The above terminology was adopted by the AFS Exotic (Introduced) Fish Section, but not without some debate. There is some disagreement with respect tothe"fishnationality"context inherent within the terminology. Some scientists argue that since fish can't possibly recognize national boundaries that the inclusion of "nationality" in terminology should be avoided. On the other hand, man does recognize national boundaries, and since a fishery is defined as a system composed of habitat, biota and man (Lackey 1974), the "nationality" usage would seem to have validity. The term introduction implies man's involvement (Kohier and Stanley 1984), and therefore should not be confused with natural migratory or invasionary movements. Fortunately, the definition quandary can be effectively resolved by referring to "introduced species" (exotics and transplants) when dealing with the topic in an ecological context, and incorporating the "political" terminology when addressing the international concerns. Appendix II

Assessment of the Impact of Major Food Fish Species Introduced into Some of the Asian Countries

The Workshop decided upon five criteria, admittedly not all of them easily evaluable nor objective, as the most appropriate means of assessing the success of the major food fish species introductions on the information available presently. The five criteria areas follows:

the introduced species is self-reproducing in natural waters and/or easily bred under hatchery conditions in the host country, the introduced species has resulted in an increase in production, the introduced species has not been responsible for transmission and/or introduction of a new disease, the introduced species has not endangered any of the indigenous fish species, and the introduced species has not had any detrimental/deleterious effects on any waters.

On this basis a total of 58 species belonging to 15 families which are consideredas food fish by each country were assessed, and the details are given in Tables All. 1-9. In certain instances a species considered as a food fish by one country may not be givena similar status by another. For example, Oreochromis mossambicus is not treated as a food fish in Australia and in Singapore. If a species has been introduced to all countries in Asia under review and is treated as a food fish by all, a total maximum score of 45 is possible. In this manner, the actual score for each species as a percentage of the maximum attainable was calculated (Table AII.1O). From the data presented itis therefore, evident that very few species have had an overall detrimental influence on the native flora and fauna. Also it should be borne in mind that in certain countries because of the prevailing socio-economic conditions and cultural preferences a species may be considered as a 'nuisance' or having a degradatory effect on the native fauna. A case in point is the role of 0. mossambicus in Indian waters; it is conceded there had been an increase in production, at least in some waters due to this species, and there is no firm evidence to show that it has brought about a decline in production or elimination of native species. In spite of these, the species is categorized as a 'nuisance' species. A similar trend of thought to be now developing with respect to Chinese bighead carp. Admittedly, it is difficult to remove these biases entirely, especially when the criteria of assessment of the success of a species are not fully objective. It is important for the readers to be aware of these apparent biases. It is also evident from the assessment tables of individual countries that few food fish introductions are associated with introduction of parasites and diseases. Most food fish introductions were made in the 1950's to late 1960's. It may be because a knowledge of

141 142

fish diseases was not well developed during this period and that some of the accidental introductions of parasites and diseases may have gone unnoticed or not attributed to the introduced species.

Table All. 1. Assessment of the status of food fish species introduced into Australia.

Species Criteria 1 2 3 4 5

SALMONTDAE Salmo gairdneri + + Salmo trutta + + - Salvelinusfontinalis + +

CYPRINIDAE Tinca tinca + + + Rutilusrsuilus + + - +

PERCICHTHYIDAE Percafluviatilir + + - +

The Atlantic salmon, Salmo salar, forms the basis of a developing fisheiy, but salmon are confined at present to cages in the sea.

Table AU.2. Assessment of the status of food fish species introduced into India.

Species Criteria 1 2 3 4 5,

CYPRINIDAE Carassiuscarassius + - + + Cyprinss carpio var. communis + + + + - Cyprinuc carpio var. specularis + + + + - Cienopharyngodon idella + + + + + Hypophthalmichthys molitrix + + + - Puntiusjavanicus + - + - +

CICHUDAE Oreochromis mossambicus + +

OSPI-IRONEMTDAE Osphronemus goramy + - + + +

SALMONIDAE Salmogairdneri + + + + + S.truttafacio + + + + + 143

Table All.3. Assessment of the status of food fish species introduction into Japan (only those species which satisfied at least one of the five criteria are included).

Taxonomic status Criteria 1 2 3 4 5

SALMONIDAE Salmo gairdneri + trulia O.kisutch + Sal velinus namaycush + S.fontinals Coregoniss lava ret us maraena +

CYPRINIDAE Aristichthys nobilis + - - Hypophthalinichthys molitrix + - - Mylopharyngodon piceus + - Rhodeus ocellatus ocellatus + + + Cyprinus carpio ruscus - - Cyprinuscarpio* + - - Megalobrama amblycephala + - Tinca tinca + -

KTALURJDAE Ictaluriss punctatus +

ATHERINTDAE Odonthestes bonariensis +

CENTRARCHTDAE Lepomis ,nacrochirus + + Micropterus salmoides + + +

CICI-ILTDAE Oreochromis aureus + - 0. ,nossambicus + + - 0. urolepis hornorum + - (reported as Tilapia macrocephala) 0. niloticus + + - Tilapia spa rrmanii + + - zulu + + -

BELONTIIDAE Macropodus chinensis + +

CHANNTDAE Channa argus + C.maculata + + 144

TableAll.4.Assessment of the status of food fish species introduction into Malaysia.

Family/species Criteria 1 2 3 4 5

CICHLIDAE Oreochromis mossambicus + + + + O.nilolicus + + + +

CYPRJMDAE Cyprinuscarpio + + + + + Cienopharyngodon idella + + + + + Aristichthys nobilis + + + + + Hypophihalmichihys nwlitrix + + + + + Labeo rohita + + + +

OSPFIRONEMIDAE Trichogaster pectoral is + + +

Table AILS. Assessment of the status of food fish species introduction into the People's Republic of China.

Family/species Criteria 1 2 3 4 5

CENTRARCHIDAE Micropterus sairnoides + Procambarus clarkii +

CHARACIDAE Colossotna bidens + + +

CICHLIDAE Oreochromis ,nossambicus + - O.niloticus + + + O.aureus + + + + Sarotherodon galilaeus - + + + T. zillii + + +

CLARUDAE Clarias batrachus + + + + C. macrocephalus + + + + C.lazera + + + +

CYPRINIDAE Carassius auratu.s cuvieri + + + Puntius gonionotus + + Catla catla + + + + Labeo rohita + + + Cyprinuscarpio + + + (Scattered mirror carp)

ICTALURIIDAE Ictalurus punctalus + + + + I. nebulosict + + + +

PANGASIDAE Pangasius sutchi + + +

SALMONIDAE Salmogairdneri + + + + + Coregornispeled + + + + Coregonus sp. + + + + 145

Table All.6. Assessment table of the statue of food fish species introduced into the Philippines.

Species Criteria 2 3 4 5

ANBANTIDAE Helostoma lem,nincki (no information)

CENTRARCHIDAE Microplerus salmoides + + + + Lepoms macrochirtss + + + + L. cyanellus (No information available)

CICHLIDAE Oreochromis mossambicu.s + + + + 0. niloticus + + + + 0. aureus (No information available) T. zulu - + + +

CLARIIDAE Clarias batrachus + + + Clarias lazera (No information available)

CYPRIMDAE Cyprinus carpio + + + + Ctenopharyngodon idella - + + Aristichthys nobilis + + + + Hypophihalmichihys molitrix + + + + Labeo rohila + + + + Catla catla (No information available) Carassius carassiu.s - + + + Cirrhinus molitorella (No information available) C. mrigal (No information available) Puntiusjavanicus + + + + Osteochilus hasselli (No information available)

ICTALURIDAE Ictaluruscatus (No known population) I. punctatus (No known population)

OSPHRONEMIDAE Trichogaster pectoralis + + + T. trichoplerus + + + + + T. leeri + (No information) Osphronemus goramy + + +

(Only those species that have had some impact on fish production is considered). 146

Table A117. Assessment of the status of food fish species introduction into Sn Lanka.

Species Criteria 1 2 3 4 5

CYPRThTDAE Aristichihys nobilis + + + Catlacatla + + + Cirrhinusmngal + Crenopharyngodonidella + + - Cyprinus carpio + + + Hypophihalmichihys molitrix + + + + + Labeo rohita + + + + +

CICHLIDAE Oreochroms mossambicus + + + + + 0. niloticus + + + + + Tilapia rendalli + + + + + Tilapia zulu + - + - +

OSPFIRONEMIDAE Osphronemus goramy + +

SALMONTDAE Salmogairdneni - + + + S.truita + + + 147 Table All.8. Assessment table of the status of food fish species introduced into Taiwan.

Species Criteria 1 2 3 4 5

FINFISH

ANGUILUDAE Anguilla anguilla

CENTRARCHIDAE Microplerus salmoides

CHARALIDAE Colossoma bidens + + + + Sciaenops ocellatus - - + + +

CICHUDAE Oreochromis mossambicus + + + O.aureus + + + O.hornorum + + + 0. nilolicus + + + Oreochromis sp. (red tilapia) + + + T. rendalli + + +

CLARIIDAE Clarias balrachu.s + + + +

CYPRIITDAE Arislichihys nobilis + + + + + Carassius auralus + + + - + Cirrhina ,noliiorella + + + + + Clenopharyngodon idellus + + + + + Cyprinuscarpio + + + - + Hypophlhalmichrhys molitrix + + + + + Leprobarbus hoevenii - - + + + Megalobrama amblycephala + + + + + Mylop/taryngodon piceus + + + + +

ICTALURTDAE Ictalurus punclatus

PANGASIDAE Pangasius cute/ti + + + + +

SALMONIDAE Salmo gairdneri

Table All.9. Assessment table of the status of major food fish species introduced into Thailand.

Species Criteria 1 2 3 4 5

CICHLIDAE Oreochromis mossambicus + + - - + O.aureus + + 0. niloticus + + - + T. rendalli + + -

CYPRINTDAE Aristichthys nobilis + - Catla caila + + - Cirrhina mrigala + + - Clenopharyngodon idellus - + - Cyprinuscarpio + + - + Hypophthalmichthys molitrLs - - + - Labeo rohita + + Thai.Table -All. Thailand) 10. The and summaiy the potential score oftotal each score food (PTS), fish species the total in score the host ('1'S) countries and the (mdi.total score- India; as Malay.a percentage - Malaya; of PTS PRC (%). - People's (+) Republic of China; SL - Sri Lanka; Taiw. - Taiwan; taken into the score analysis. Family/Species Aust. mdi. Jap. Malay. Countries introduced into PRC Philip. SL - introduced but no information available and were notTaiw. Thai. PTS Score analysis TS ANGUILLIDAEANABANTJDAE Helostoma temminicki + 5 3 ATHERINIDAE AnguillaOdonthestes anguilla bonariensis + + 5 1 2060 CENTRARCHTDAEBELONIIDAE Macropodus chinensis + 5 2 40 ProcambarusMicropterusL.Lepomis cyanellus ,nacrochirus salmoides clarkii ++ + + + 2010 5 15 73 706075 CHARACIDAECHANNIDAE C.Channa maculata argsts -1- + 5 2 1 4020 CICHLIDAE OreochromisaureusColossoma bidens + + + + + 2010 11 7 70 55 Sarotherodon0.O.mossambicusO.hornorwn niloticus galilaeus + ++ + + ++ + + + + ++ 354010 5 2829 53 50 608073 CLARI[DAE T.Tilapia zulusparrmanii rendalli + + + + + + + 2015 5 1211 2 604073 CYPRINIDAE C.C.lazeraClarias batrachus crccepha!us ++ + + 155 125 44 Continued go80 AristichihysCatlaC.Carassiusauratus carassius cotta nobilis (varieties) + + + + + + + + 30 1510 1122 7379 737090 Table All.10. Continued Family/Species Aust. mdi. Jap. Malay. PRCCountries introduced into Philip. SL Taiw. Thai. PTS Score analysis TS % CtenopharyngodonCirrhinus pnolitorellamrigal idella + + + + + + + 3510 5 25 64 716080 LeptobarbusLabeoHypophzhalmichthysCyprinus rohia carpiohovenii molirrix + + + + + ++ + + 253540 5 202532 3 608071 PuntiusMy!MegalobramaOsteochilu opharyngodon gonionotus amblycephalahasselti picejis + + + + 10 5 46 608060 TincaRutilusRhodeP. javanicus tinca us rutilus ocellatus ocellatus + + + + 10 55 43 40606080 ICTALURIDAE I.LcatusIctaluruspunctatus nebulosus + + + + 15 5 - 48 8053 - OSPRRONEMIDAE TrichogasterOsphronemus pecloralis gouramy + + + 15 12 80 T. leeri + + T. Irichopterus + 10 5 58 100 80 PERCICHTHIDAEPANGASIDAE Pangasius sutchi + 10 9 90 SALMONIDAE CoregonusPercafluviasilis peled + + + 10 5 53 5060 SalmogairdneriOnchorhynchusC.C.sp. lavaretus maraena kisutch + + + + + 5 21 14 2080 S.Salvelinusfontinalis namaycushtrutta + + + + 203010 5 12 13 20306070 Appendix III

Instances of Decline/Disappearance of Indigenous Species as a Possible Consequence of Introduced Fish Species

It will be apparent from the individual presentations that the number of instances, in the area under review, that an indigenous species was made extinct or endangered as a consequence of an introduction were few. Nevertheless, this is no reason for complacency. Also, in certain instances though the decline of indigenous species has been attributed to an exotic i:he evidence available is mostly circumstantial. In spite of these shortcomings this Appendix summarizes such instances.

150 151 Table Affi. Indigenous species which are known to be endangered andor declined as a result of introductions in different countries.

Countiy/Species Locality Status Reasons Authority

AUSTRALIA Melanotaenja eachamensjs Lake Eacham Extinct (?) Translocation of Banao et (Lake Eacham rainbow fish) Queensland (IUCN) mouthbrooder al. (1987) Glossania apricu

Galaxia.sfanianu.s Swan River Endangered Introduction of Michaelis (1985) (Swan galaxias) Tasmania Salrno trutta

Galaxtasjohnstani Clarence river, Endangered Introduction of do (Clarence galaxias) Tasmania Salvelinusfontiia1is

INDIA Cat/a cat/a Some reservoir Decline in Introduction of Shetty et al. populations catches silver carp pres. volume

JAPAN Rhodeu.s' ocellatu.s smithi Endangered Introduction of Chiba et al. R.o. ocellatus pres. volume

MALAYSIA Trichogaster Paddy fields, Endangered(?) Introduction of Ang et al trichopterus swamps T. pectoralis present volume (Snakehead gouramy)

PIT11UPPINES Mistichihys luzonensis Lake Buhi Extinct(?) Introduction of Baluyut (1988), (Sinarapan) T. mossambica De Silva, Native Cyprinid Lake Lanao Endangered(?) Introduction of Juliano et al. Flock Glossogobiu.s (pres. vol.) & giuris Frey (1969)

TAIWAN Macropodu.s opercularis almost extinct Due to the Liao & Liu introduction of (pres. vol.) Ainpullarius insularu,n

Clariasfuscu.s almost extinct C/arias batrachus do

Oryzias latipes extinct Gambzesia affinis do

Leiobagru.sfosmosanus population has Micropterus salmoides Liao & Chiu Leiocassis adiposalis been greatly (pres. vol.) reduced

Rhyacichthys aspro population has Poecilia velifera do Mesopristes cancel/at us been greatly reduced

Erylhroculter ilishaeformis extinct Tilapia zulu do Oreochromis aureus 0. mossambicus 0. niloticu.s

Capoeta semfa.sciolata population has Tricogasrer trichopterus do been greatly reduced Appendix IV

Ornamental Fishes

The inclusion of lists of exotic ornamental fishes in each of the countries in the proceedings will not be a realistic task. In the text lists of ornamental fishes introduced into Malaysia, People's Republic of China, Singapore, Taiwan and Thailand are included in each of the papers on these countries. A list of ornamental fishes introduced to Australia is available from Mr. R. McKay (also in diskette from IBM Compatible PC). The Indian Branch of the Asian Fisheries Society has prepared a list of ornamental fish introduced into India, and this will be published in the Proceedings of the Workshop on Exotic Organisms in India. The particular reference is: Bhaskan, I.S., Reddy, P.S., Elambarathy, B., Subranianium, B. and Lazarus, R.J. (in press), Exotic freshwater aquarium fishes and their role in the aquarium fish trade of India. In addition lists of aquarium fishes introduced into some of the other countries are documented in: Conroy, D.A. (1975), An evaluation of the present state of world trade in ornamental fish. FAO Fisheries Circular No. 335, pp. 120. The Committee on Exotic Fishes of the Asian Fisheries Society will attempt to publish a separate document on ornamental fishes in the near future. As much as interest is created in the exotics, there is a need to conserve the stocks of ornamental fish exported from each of the countries in the region because some of the species exported are endemic to specific countries/habitats, and are already cited as endangred species in the IUCN's red data book.

152 Appendix V

Existing Legislation or Code of Practices Adopted by Individual Countries in Respect of Introducing Aquatic Species

The operative legislation of some of the countries has been dealt with in the individual presentations. In this Appendix, a summary of the legislation, and in the event there is no legislation the mechanisms that operate in deciding on introducing a species to that country, is presented.

AUSTRALIA:

The operative legislation covers all plant and animal introductionsto Australia by the Wildlife Protection (Regulation of Export Imports) Act 1982 of the Commonwealth (Federal) Government. The Act is administered by the Australian National Parks and Wildlife Service, and on matters regarding aquatic species technical advice is rendered by the Advisory Committee on Live Fish (ACOLF) of the Australian Fisheries Council. The ACOLF also serves in an advisory capacity for inter-state translocations. Australia is also a signatory to the CITES and the SPREP conventions.

INDIA:

There is no existing legislature on the importation/introduction of aquatic organisms. However, the Indian Council for Agricultural Research, through the Commissioner of Fisheries, decides on any proposed introductions. India is also a signatory to CITES.

INDONESIA:

Indonesia has recently adopted the code of practice developed by the European Inland Fisheries Advisory Committee (EIFAC) for the introduction of aquatic organisms (Artmadja Hardjumulia, pers. comm.). However, this informal adoption has yet to be legalized.

JAPAN:

There are no restrictions or rules governing introduction of exotic species into Japan. Japan is a signatory to CITES and is only bound by this convention.

153 IDRC CR11

154 Mi101 rnFIN257598 MALAYSIA: The present Fisheries Act 1984, which replaced the Fisheries Act 1963, governs the introductions into Malaysia and also translocations between West Malaysia to Labuan or Sabah and Sarawak and vice versa. The Director General of Fisheries is empowered by Section 40(2) of the Act to issue permits for introductions, and to establish and determine the quarantine procedure and facilities. The above Federal Statute is an addition to the number of State enactments some of which have been in existence since 1934. Malaysia is also a signatory to the CITES.

PHILIPPINES:

There are no laws governing the introduction of aquatic organisms. Most research institutes and universities however, follow strict quarantine measures with imported species.

SRI LANKA:

There are no laws governing the introduction of aquatic organisms per Se. However, the strict customs regulations act as a safety valve, and imported live organisms are expected to be brought into the country on the recommendation of Zoological Gardens, The Department of Agriculture and in the case of aquatic species, the Ministry of Fisheries. The deliberate release of aquatic organisms in the wild can be carried out only on the authority of the Ministry of Fisheries. Sri Lanka is a signatory to CITES.

TAIWAN:

There are still no laws/regulations governing the importation of aquatic organism into Taiwan. However, a few governmental organizations have some regulations with respect to certain types or species of fish. Importation of food and ornamental aquatic organisms is under the jurisdiction of the Taiwan Fisheries Bureau and the Council of Agriculture. The final authority for issue of permits lies with the Executive Yuan of the Council of Agriculture, which acts on the advice of Taiwan Fisheries Bureau.

THAILAND:

A Royal Decree in 1953 prohibited the introduction of many exotic animals and plants. It was amended in 1982 and was made into law in 1983. The law prohibits the introduction of 176 species of fish, 21 species of invertebrates and 16 species of algae. TITLES IN THE ASIAN FISHERIES SOCIETY SPECIAL PUBLICATION SERIES

Fish Quarantine and Fish Diseases in South and Southeast Asia: 1986 Update. 1987. Edited by J.R. Arthur. Asian Fish. Soc. Spec. Pub!. 1,86 p. Price: Members, free. Nonmembers, US$5.

Fisheries Education and Training In Asia: Workshop ProceedIngs. 1988. Asian Fish. Soc. Spec. Pub!,2, 162 p. Price: Members, free. Nonmembers, US$8.

Exotic Aquatic Organisms In Asia. 1989. Edited by S.S. Dc Silva. Asian Fish. Soc. Spec. Pub!. 3, 154p. Price: Members, free. Nonmembers, US$8. -