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ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityPublished by the Secretariat of the ong>Conventionong> onBiological Diversity. ISBN: 92-807-2406-1Copyright (c) 2004, Secretariat of the ong>Conventionong>on Biological DiversityThe designations employed and the presentation ofmaterial in this publication do not imply theexpression of any opinion whatsoever on the partof the Secretariat of the ong>Conventionong> on BiologicalDiversity concerning the legal status of any country,territory, city or area or of its authorities, orconcerning the delimitation of its frontiers orboundaries.The views reported in this publication do not necessarilyrepresent those of the ong>Conventionong> onBiological Diversity nor those of the reviewers. Thispublication may be reproduced ong>forong> educational ornon-profit purposes without special permissionfrom the copyright holders, provided acknowledgementof the source is made. The Secretariat of theong>Conventionong> would appreciate receiving a copy ofany publications that uses this document as asource.CitationSecretariat of the ong>Conventionong> on BiologicalDiversity (2004) ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong>- avoiding the adverse effects of ong>maricultureong> onbiological diversity (CBD Technical Series no. 12).For further inong>forong>mation, please contact:Secretariat of the ong>Conventionong>on Biological DiversityWorld Trade Centre393 St. Jacques Street, suite 300Montreal, Quebec, Canada H2Y 1N9Phone: 1 (514) 288 2220Fax: 1 (514) 288 6588E-mail: secretariat@biodiv.orgWebsite: http://www.biodiv.orgLayout and printing: COMMUNICATIONS CDGPhoto credits:Woman: R.J.ROSS/PETERARNOLD/ALPHA PRESSEShrimp and fish farm: C.RUOSO/BIOS/ALPHAPRESSEFish farm: UNEP/ALPHA PRESSESalmon fish farm: J.P. SYLVESTRE/BIOS/ALPHAPRESSE2


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityFOREWORDThe programme of work on marine and coastalbiodiversity aims to assist the implementation ofthe Jakarta Mandate at the national, regional andglobal level. It identifies operational objectives andpriority activities within the five key programmeelements, namely: implementation of integratedmarine and coastal area management, marine andcoastal living resources, marine and coastal protectedareas, ong>maricultureong> and alien species and genotypes.Mariculture - the production of marine organismsong>forong> food - represents an opportunity to provide aong>sustainableong> supplement to the marine capture fishery.Mariculture has a relatively long history; ong>forong>example, oyster culture was known to the Romans.By contrast, modern, intensive ong>maricultureong> is onlyapproximately 30 years old, producing a steadilyincreasing proportion of the world’s seafood duringthis period. Aquaculture production currentlyexceeds freshwater capture by a factor of more thanthree and makes up almost half of the marine capturefisheries. Moreover, aquaculture productionhas more than doubled over the last ten years andthis trend is continuing whilst traditional fishingproduction is declining as a result of overexploitation.But aquaculture, both in inland waters andmarine and coastal areas, has problems, includinghabitat degradation, disruption of trophic systems,depletion of natural seedstock, transmission of diseases,and reduction of genetic variability. To solvethese problems inong>forong>mation is needed to improveits sustainability. In particular, we need to betterunderstand possible interactions between aquacultureand natural environments to minimize thepotential ong>forong> habitat degradation, introduction ofinvasive alien species, etc.The objective of this document is to provide a basisong>forong> understanding the effects of ong>maricultureong> onmarine and coastal biological diversity. The presentreport is a result of a ong>forong>um in which researchersreviewed the scientific knowledge base ong>forong> thedevelopment of a ong>sustainableong> ong>maricultureong>. It is myhope that this report is a contribution to developgreater depth in domestic research, as well as tobuilding connections between the researchers.This report is being widely distributed to reach outto public sectors, research centres and to otherinterested parties. I am confident that the lessonslearned from these efong>forong>ts will provide valuableinput as the ong>Conventionong> continues to promote andfacilitate achievement of the target of significantlyreducing the current rate of biodiversity loss by theyear 2010.I thank all of those individuals and institutions whohave contributed to the preparation of this technicalreport.Hamdallah Zedan3


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityAcknowledgementsThe Secretariat of the ong>Conventionong> on BiologicalDiversity wishes to acknowledge with appreciationthe Food and Agriculture Organization of theUnited Nations (FAO) ong>forong> the technical supportand meeting facilities provided ong>forong> the meeting ofthe Ad Hoc Technical Expert Group onMariculture. The Secretariat would also like toexpress its gratitude to the members of the Ad HocTechnical Expert Group on Mariculture ong>forong> developingthis document; to Ms. Stella Williams ofNigeria and Mr. Phillippe Goulletquer of Franceong>forong> chairing the meeting of the expert group; and tothe observers and resource personnel ong>forong> theirinvaluable contributions. Finally, the Secretariatwould like to thank the World Fisheries Trust ong>forong>preparing the background document ong>forong> the meetingof the expert group.4


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityLIST OF AUTHORSThis document was produced by the Ad HocTechnical Expert Group on Marine and CoastalProtected Areas. The expert group members, includingobservers are (in alphabetical order):Mr. A.K. Armah (Ghana)Ms. Daisy C. Arroyo Mora (Costa Rica)Mr. Uwe Barg (FAO)Mr. Devin Bartley (FAO)Mr. Stefano Cataudella (Italy)Mr. S.U.K Ekaratne (Sri Lanka)Ms. Vlasta Franicevic ´ (Croatia)Mr. Phillippe Goulletquer (France - Co-chair)Mr. Alessandro Lovatelli (FAO)Mr. Terry McMahon (OSPAR Commission)Mr. Manal Nader (Lebanon)Mr. Fabian Pina Amargos (Cuba)Ms. Shyama Rathacharen (Mauritius)Mr. Arturas Razinkovas (Lithuania)Mr. Tetsuo Seki (Japan)Mr. Mohamed Shariff (Malaysia)Ms. Doris Soto (Chile)Mr. Uwe Waller (Germany)Ms. Stella Williams (Nigeria - Co-chair)Ms. Fatimah Md.Yusoff (Universiti Putra Malaysia)Mr. Serguei Zagranitchnyi (Russia)^The following also contributed considerably to thisdocument:Mr. David Coates (CBD Secretariat)Ms. Beatriz Gomez-Castro (CBD Secretariat)Mr. Kalemani Jo Mulongoy (CBD Secretariat)Ms. Marjo Vierros (CBD Secretariat)5


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityEXECUTIVE SUMMARYThe Ad Hoc Technical Expert Group onMariculture was established by the Conference ofthe Parties in adopting the programme of work onmarine and coastal biological diversity at its fourthmeeting (decision IV/5, annex). The Expert Groupwas established to assist the Subsidiary Body onScientific, Technical and Technological Advice(SBSTTA) in its work on the topic of ong>maricultureong>.The terms of reference instructed the Expert Groupto:(a)(b)Evaluate the current state of scientific andtechnological knowledge on the effects ofong>maricultureong> on marine and coastal biodiversity;Provide guidance on criteria, methods, techniquesand best practices that avoid theadverse effects of ong>maricultureong>, and also subsequentstock enhancement, on marine andcoastal biological diversity and enhance thepositive effects of ong>maricultureong> on marine andcoastal productivity.In evaluating the current state of knowledge on theeffects of ong>maricultureong> on marine and coastal biodiversity,the group identified the main ong>maricultureong>species and methods, and the biodiversity effects ofthose methods (Chapter 2). The group agreed thatall ong>forong>ms of ong>maricultureong> affect biodiversity at thegenetic, species and ecosystem level, but that undercertain circumstances ong>maricultureong> could alsoenhance biodiversity locally (Chapter 4). The maineffects include habitat degradation, disruption oftrophic systems, depletion of natural seedstock,transmission of diseases, and reduction of geneticvariability. The biodiversity-effects of pollutantssuchas chemicals and drugs - are not very well studied,though are generally assumed to be negative.There are many available methods and techniquesong>forong> avoiding the adverse effects of ong>maricultureong> onbiodiversity, and they are summarized in Chapter 3of this document. They include, most importantly,proper site selection, as well as optimal managementincluding proper feeding. Other mitigationmeasures include culturing different speciestogether (polyculture), and the use of enclosed, andespecially re-circulating, systems. Many of theother impacts can be avoided with better managementpractices and other technological improvements.A number of aquaculture-specific internationaland regional principles, standards and certificationprocesses exist, and are described inChapter 5 of this document.6


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ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversity1. BACKGROUND1. The Ad Hoc Technical Expert Group onMariculture was established by the Conference ofthe Parties in adopting the programme of work onmarine and coastal biological diversity at its fourthmeeting (decision IV/5, annex). The Expert Groupwas established to assist SBSTTA in its work on thetopic of ong>maricultureong>. The terms of reference ong>forong> theGroup were approved by the Conference of theParties at its fifth meeting, in decision V/3. Thework of the Group is intended to help implementprogramme element 4 (Mariculture) of the programmeof work on marine and coastal biologicaldiversity. The operational objective of this programmeelement is as follows:“To assess the consequences of ong>maricultureong> ong>forong>marine and coastal biological diversity and promotetechniques which minimize adverse impact.”2. In its terms of reference the Group was requestedto:(a) Evaluate the current state of scientific andtechnological knowledge on the effects of ong>maricultureong>on marine and coastal biodiversity;(b) Provide guidance on criteria, methodsand techniques that avoid the adverse effects ofong>maricultureong>, and also subsequent stock enhancement,on marine and coastal biological diversityand enhance the positive effects of ong>maricultureong> onmarine and coastal productivity.3. In decision V/3, paragraph 15, of the Conferenceof the Parties, the Group was also asked to identifybest practices in ong>maricultureong>.(France) as its Co-Chairs, and Ms. Doris Soto(Chile) and Mr. Mohamed Shariff (Malaysia) asRapporteurs. The staff of the FAO FisheryResources Division provided logistical and technicalsupport ong>forong> the meeting.5. The Expert Group addressed the issues containedin its terms of reference as requested by theConference of the Parties and the present reportthus provides an evaluation of the current state ofscientific and technological knowledge on theeffects of ong>maricultureong> on marine and coastal biodiversity;and guidance on criteria, methods, techniquesand best practices that avoid the adverseeffects of ong>maricultureong> on marine and coastal biologicaldiversity, and enhance the positive effects ofong>maricultureong> on marine and coastal productivity.6. Chapter 2 of the present note presents an evaluationof the current state of scientific and technologicalknowledge on the effects of ong>maricultureong> onmarine and coastal biological diversity. This chaptercorresponds to part (a) of the terms of reference,and reviews the main ong>maricultureong> species,methods and their impacts. Chapter 3 presents criteria,methods, best practices and technology ong>forong>avoiding the adverse effects of ong>maricultureong> onmarine and coastal biodiversity, while Chapter 4discusses enhancing its positive effects. Thesechapters correspond to part (b) of the terms ofreference. Additionally, a summary of existinginternational and regional guidance on ong>maricultureong>is provided in chapter 5 of the report.4. The Expert Group met from 1 to 5 July 2002, atFAO headquarters in Rome. The complete list ofmembers of the Group is contained in Annex I tothis document. The Expert Group elected Ms. StellaWilliams (Nigeria) and Mr. Phillippe Goulletquer9


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityB. METHODS12. This document focuses on the most importantand well-documented species and methods, anddoes not attempt to embrace all species and methods.Despite the huge variety of marine organismscultured, the methods used can be reduced to a fewbasic strategies. While there are numerous schemesong>forong> grouping kinds of aquaculture (e.g. autotropicvs heterotrophic), the ong>maricultureong> methods presentedhere are grouped in a common-sense waythat makes it easy to identify and visualize theirbiodiversity effects. Detailed inong>forong>mation abouteach culture method is provided in the full reportof Expert Group. The culture categories are:(a)(b)For molluscs:(i) Vertical or rack culture;(ii) Hanging culture;(iii) Bottom culture;(iv) Land-based tank culture;(v) Sea ranching;For echinoderms:(i) Tank culture;(ii) Cage culture;(iii) Sea ranching;(c) For crustaceans:(i) Pond culture;(ii) Raceway culture;(iii) Cage culture;(iv) Sea ranching;(d) For marine aquatic plants:(i) Suspended culture (longline, raft, net) ;(ii) Bottom culture;(iii) Tank culture;(e) For finfish:(i) Cage culture (inshore and offshore);(ii) Pen culture;(iii) Pond and raceway culture (flow-throughand recirculation systems);(iv) Sea ranching.13. Polyculture, the growing of two or morespecies belonging to different trophic levels in thesame system, has a long history in freshwater aquaculture,especially in China. Some marine examplesinclude grouper and mudcrab in ponds; milkfishand siganids in marine net cage; sea scallops suspendedfrom salmon net pens; shrimp and scallop;and ezo scallop, Japanese kelp and sea cucumberare cultured in combination with open-water mariculturalstructures like net cages ong>forong> finfish.14. The following section briefly describes themain ong>maricultureong> methods. Broodstock, seed supplyand growout are considered separately ong>forong> eachmethod, as these very different activities have fundamentallydifferent effects on biodiversity.1. Mollusc culture15. Mollusc culture is done in tropical and temperateregions depending on species. Oysters, scallopsand mussels are dominating the temperateong>maricultureong> while in tropical areas the same speciesare cultured at a low and local commercial scale.Broodstock and seed supply16. Bivalve mollusc larvae or “spat” are either collectedfrom natural grounds using suitable materialsto which the larvae adhere or “set”, or producedby artificial fertilization in hatcheries. The lattertechnique allows much greater control over thegenetic makeup of the stock, as well as transport ofthe larvae to distant grow-out facilities (“remotesetting”). The parental stock usually comes fromnatural environments, is maintained ong>forong> short periods,and spawning is induced in captivity. Thus it islikely that the offspring retain the genetic diversity12


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityof the parental stock. Nevertheless, due to the highfecundity of molluscs, only few animals arerequired to sustain seed production, a practicewhich might cause negative impacts on the geneticdiversity of the reared population. Studies areunderway to define the required number of broodstockin order maintain genetic diversity. 317. In many areas, triploid production of spats arecarried out in order to decrease the growth period.Triploid organisms do not pose a genetic problemas they are sterile. Nevertheless, 100% triploidy isnot guaranteed and monitoring ong>forong> permanentsterility is highly recommended. In oysters, a reversionto fertile condition after triploidy inductionhas been observed 4 . Thereong>forong>e, triploidy should beconsidered as a risky process ong>forong> a species introduction,requiring first a containing system. On theother hand, tetraploids are cause ong>forong> more concernas they can breed with wild populations and produceinfertile offspring. Research is required to elucidatethe potential biodiversity impact of such practices.Growout18. Larvae that have attached or “set” to their substrateare grown in hanging culture (suspendedfrom floating rafts or floating long lines on strings,trays, stacks or mesh bags), vertical or rack culture(sticks or posts are staked on the bottom and actdirectly as a growing medium or support racks, orplatong>forong>ms), bottom culture (shells, stones, rocks,cement slabs etc. added to the bottom provideattachment sites), or in land-based systems (mostlyong>forong> sea-ranching). In the case of abalone, landbasedculture techniques are applied ong>forong> the wholelife cycle. 519. Hanging culture is the most common methodof oyster, mussel and scallop culture. In France,oysters are cultured both on and off the bottom,using trestles, to produce the regularly shaped shellspreferred by raw half shell consumers. 67 Commercialclam growers and quahog culture operationsdepend largely on bottom culture. 8 Mussel farmingmakes extensive use of bamboo either as stakes oras floating rafts with the vertical or rack culturemethod most commonly used. 9 Seed scallops aremost commonly suspended in the water from rafts,frames or longlines, sandwiched in metal or plasticmesh frames, hung in fine mesh lantern nets (shallowwater cages) or pearl nets (deep water cages) orhung individually from strings (ear hanging). 1020. Aquaculture has also been used to restore andreplace overfished stocks of molluscs. In overfishedstocks, a restoration management plan should beadopted to conserve natural genetic diversity as theexpansion of ong>maricultureong> increases the risk on wildpopulations. 1121. Given the specificities of each mollusc culturemethod, different impacts on biodiversity are to beexpected. Most culture methods make use of naturalprimary productivity and thereong>forong>e the carryingcapacity of the system should be carefully considered.In addition, sedimentation from faeces contributesto nutrient flows. Maintenance of culturestructures sometimes includes the use of antifoulingchemicals. Regardless of the applied technique,3 Ikeda M. and Taniguchi N 2002 .Genetic variation and divergence in populations of ayu Plecoglossus altivelis, including endangered subspecies,inferred from PCR-RFLP analysis of the mitochondrial DNA d-loop region. The official Journal of the Japanese Society of Fisheries, 68:18-274 Blankenship, K. 1994. Experiment with Japanese oysters ends abruptly. Bay Journal 10:1-4. Cited in OTA (1995).5 McKenzie C.L. Jr and V.G. Jr. Burrell, 1997. Trends and status of molluscan fisheries in North and Central America and Europe-A synopsis.Marine Fisheries Review, NOAA Technical Report NMFS, 129:1-15.6 Bardach, J. E, J. H. Ryther, and W. O. McKarney. 1972. Farming and Husbandry of Freshwater and Marine Organisms. John Wiley & Sons, Inc.7 Goulletquer P. and M. Héral, 1997. History, present conditions and future of the Molluscan fisheries of North America and Europe. MarineMolluscan production trends in France: from fisheries to aquaculture. Marine Fisheries Review, NOAA Technical Report NMFS, 129:137-164.8 Bardach, J. E, J. H. Ryther, and W. O. McKarney. 1972. Farming and Husbandry of Freshwater and Marine Organisms. John Wiley & Sons, Inc.9 Baluyut, E. A. 1989. Aquaculture systems and practices: a selected review. UNEP/FAO, Rome. ADCP/REP/89/43.http://www.fao.org/docrep/T8598E/t8598e00.htm#Contents10 Bardach, J. E, J. H. Ryther, and W. O. McKarney. 1972. Farming and Husbandry of Freshwater and Marine Organisms. John Wiley & Sons, Inc.11 Stotz W, 2000 When aquaculture restores and replaces an overfished stock: Is the conservation of the species assured? The case of the scallopArgopecten purpuratus in the northern Chile. Aquaculture International, 8: 237-24713


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversitythe water column and the sea floor are subject toalteration in their biological composition. In thecase of land-based abalone culture, artificial food isused as supplement to natural feed. This requirestreatment of effluents in order to reduce impactson the natural ecosystem. 122. Crustaceans22. Shrimp ong>maricultureong> is mostly practised in tropicalregions and some attempts are made to produceshrimp in temperate areas in pond and recirculatingsystems.Broodstock and seed supply23. Until the last decade, the global shrimp andprawn farming industry relied on wild-caught larvaeor larvae produced by wild-caught females carryingfertilized eggs (“berried females”). Theseactivities have had great adverse impacts on naturalstocks. 13 The removal of gravid females reduces theavailability of shrimp larvae, a major source of foodong>forong> many aquatic organisms. Furthermore, thebycatch of non-target species is an impact on theenvironment. With the expansion of shrimp farmingand especially the need to ensure the supply ofdisease-free post-larvae (the stage at which artificialfeeding and growout in tanks starts), the trendis toward maintenance of broodstock in hatcheriesand the complete closing of the life cycle in captivityusing induced spawning techniques. Such controlledreproduction of farmed crustaceans hasgreatly reduced dependence on natural supplies ofseed. A major consideration of such techniques liesin the loss of the genetic diversity of the culturedspecies (in case of escapes).24. Seed overproduction in some hatcheries andtheir subsequent release into the wild results inenhancement of natural populations. 14 Anotherproblem is posed by the transfer of broodstock andhatchery-produced larvae to different growingregions of the globe. In all cases, effects on geneticdiversity should be considered.Growout25. In the early days of shrimp farming, ong>forong> examplein China, shrimp culture was done in “trapponds” where juveniles were allowed to enter andgrow to marketable size. 15 Presently, shrimp aregrown in earthern ponds, concrete raceways andtanks in extensive, semi-intensive, and intensiveculture systems. Environmental impact depends onthe level of stocking density applied: extensive culturerequires large areas and intensive culture useshigh quantities of artificial food and high waterexchanges. Extensive aquaculture promotes thenatural production of the pond, semi-intensiveaquaculture supplements natural production withartificial feed, while intensive aquaculture requiresartificial feed as the addition to the natural organismsin the water as a source of nutrition. 1626. In many countries, shrimp ponds used to berice fields, mangrove ong>forong>ests, fish ponds or salt pans(ong>forong> example, milkfish ponds in the Philippines,mangroves in Ecuador and other countries). 17Rapid expansion of shrimp ong>maricultureong> led to thedestruction of vast areas of mangroves disrupting12 Allen V.J., I.D. Marsden, N.L.C. Ragg, 2000. The use of stimulants as an aid to wean fishery-caught blackfoot abalone Haliotis iris to artificalfood. Journal of Shellfish Research, 29(1):501.13 FAO. 2001. Report of the FAO/Government of Australia Expert Consultation on Good Management Practices and Good Legal and InstitutionalArrangement ong>forong> Sustainable Shrimp Culture, Brisbane, Australia, 4-7 December 2000. FAO Fisheries Report No. 659, Rome, Italy, 70pp.14 Davenport J.; Ekaratne S.U.K.; Walgama S.A.; Lee D.; Hills J.M. (1999) Successful stock enhancement of a lagoon prawn fishery at Rekawa, SriLanka using cultured post-larvae of penaeid shrimp. Aquaculture, 1 October 1999, vol. 180, no. 1, pp. 65-78(14)15 FAO. 1978. Aquaculture development in China. Report on an FAO/UNDP Aquaculture Study Tour to the People's Republic of China, led byT.V.R. Pillay, Aquaculture Development and Coordination Programme, FAO, Rome, Italy, 2 May-1 June 1978.http://www.fao.org/docrep/X5686E/X5686E00.htm16 Baluyut, E. A. 1989. Aquaculture systems and practices: a selected review. UNEP/FAO, Rome. ADCP/REP/89/43.http://www.fao.org/docrep/T8598E/t8598e00.htm#Contents17 The Trade and Environment Database, Case Studies, Thailand Shrimp Farming. http://www.american.edu/TED/THAISHMP.HTM14


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversitythe balance of these special ecosystems. However,efong>forong>ts are now underway to restore mangrovehabitats. In some countries, shrimp aquaculture isnow being practised in inland ponds using transportedseawater. Even though this technique mightbe beneficial in terms of saving mangroves andrestricting the spread of disease, it has negative effectson soils, terrestrial and inland water environments.27. Pond culture systems result in vast flows ofnutrients and solids to natural environments withmarked impacts on ecosystems and their biodiversity.Another major impact associated with shrimpaquaculture is the spread of disease to natural populations.Chemical inputs to the environmentcome from different sources like medicated feedand application of pesticides and insecticides.Shrimp aquaculture production decreased tremendouslyin the past decade due to disease problems,poor management techniques, lack of coastal planningand inappropriate site selection. New techniquesare being developed such as zero exchangesystems that confine the cultured animals andrequire limited amounts of water, thereong>forong>e reducingthe interaction between cultured animals and theenvironment.3. Marine aquatic plant culture28. Macro- and micro-algae and seagrass cultureis mostly practised in temperate, but also in tropicalregions ong>forong> human use (i.e. cosmetics and consumption).In the industrial sector, many uses have beenidentified, such as the development of agar products.Broodstock and seed supply29. Cultured aquatic plants generally have complicatedlife cycles with several intermediate stages.The major source of broodstock is wild collectionof specimens. Most culture of aquatic plants is nowdependent on hatchery production of the early lifestages (monospores, zoospores, gametophytes,sporophytes) which are attached to growing mediaand transferred to marine sites. Other propagationmethods involve fragmentation and protoplasttechniques. In East Asia, selective breeding basedon phenotypic characteristics is widely practised.Growout30. Young plants are cultured by three differentmethods: suspended (longline and raft), bottomcultures at sea, and inland tank cultures.31. In bottom culture, large rocks or artificial substratesuch as various shapes of concrete are placedon the seabed and either seeded with zoospores (anearly life stage) or have sporophytes (young plants)anchored to them using rope. Bottom culture, nowoften used in conjunction with raft culture, is theearliest known ong>forong>m of kelp culture but is stillemployed in China, as well as in Japan and Korea. 1832. In off-bottom culture, monospores (anotherearly life stage) or young plants are either suspendedfrom weighted rope lines or attached directly tolines or culture nets. These ropes and nets areattached to floating rafts, buoyed longlines, fixedlonglines or fixed pole structures and frames.Porphyra, “nori” (laver) concosellis containing oystercultch are attached to culture nets in the laboratory,and the nets are suspended from wooden orbamboo frames anchored to the bottom in shallowcoastal areas or inland seas. 19 Laminaria spp. andUndaria spp., “wakame” is cultured in open wateron longlines that can reach depths of up to 6 metersdepending on water clarity. 20 The fixed off-bottommonoline method is the most common methodused in the culture of Eucheuma spp. Raft orlong-line methods are also used. 21 Gracilaria spp.18 Bardach, J. E, J. H. Ryther, and W. O. McKarney. 1972. Farming and Husbandry of Freshwater and Marine Organisms. John Wiley & Sons, Inc.19 Ibid.20 Ibid.21 FMC BioPolymer website. FAQ on the benefits of cottonii and spinosum seaweed farming. http://www.fmcbiopolymer.com/contents/seaweed_farming/index.cfm?scrn=faq&answer=4#415


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityculture in Chile uses a technique resembling agriculture,where the algae are planted on sand bottoms.4. Finfish33. Finfish culture is practiced in both temperateand tropical waters. In the case of tropical waters,there is a need of biological studies ong>forong> seed production.Species cultured include both catadromousand marine fish.Broodstock and seed supply34. Broodstocks are divided into two main categories:(i) domesticated and (ii) a mixture betweenwild and domesticated. In the case of domesticatedbroodstocks, great concern is expressed regardingthe conservation of genetic diversity. Less impacton genetic diversity is expected if wild fish are usedin combination with domesticated animals.Nevertheless, this last method will put undesiredpressure on wild stocks by promoting the captureof wild organisms. More research is needed inorder ong>forong> the industry to adopt the best techniquein terms of reducing biodiversity impacts. As anexample, the introduction of 100 to 200 Nile tilapiafry supports a 90,000 ton aquaculture harvest, suggestinga low genetic diversity. 2235. Most of the important finfish species are grownfrom larvae or “fry” produced by controlled reproductionin hatcheries. Induced breeding technologyhas progressed through the application of crudepituitary homogenates to the development of highlyactive gonadotropin-releasing hormone analoguesthat can stimulate spawning in recalcitrantspecies or through the manipulation of holdingconditions. 23 24 Of all the major marine finfish speciescultured, salmonids are the main group ong>forong> whichgametes can be stripped from wild fish and combinedlater in the hatchery, the technique most commonlyused ong>forong> seed production. For most tropicaland warm-water (sea bass and sea bream) species, andong>forong> some salmonids held in captivity beong>forong>e breeding,spawning is initiated by hormone application.36. Collection of fry from the natural environmentaffects recruitment into wild populations byreducing the parental stocks. In the case of the collectionof Atlantic glass eel, this could lead to thecollapse of the natural reproductive stocks. 25 InMediterranean, Asian and Latin American countries,seed is still being collected from the wild. InEgypt, ong>forong> example, fry of mullets, sea bream andsea bass still derive primarily from the wild. 2637. In many areas triploid production of seed arecarried out in order to decrease the growth period.A second potential advantage is the production ofsterile offspring. Nevertheless, this requires ensuringthat the fry are all female triploids as the disruptionof gonadal development may not be fullyachieved in males. 27 On the other hand, tetraploidsare cause ong>forong> more concern as they can breed with28 29 30wild populations and produce infertile offspring.22 Beardmore, J. A., Mair, G. C., and Lewis, R. I. (1997) Biodiversity in aquatic systems in relation to aquaculture Aquaculture Research,28(10): 829-839.23 Harvey, B., and J. Carolsfeld. 1993. Induced breeding in tropical fish culture. IDRC. Ottawa, Ont. 144pp.24 Zohar, Y., and C. C. Mylonas. 2001. Endocrine manipulations of spawning in cultured fish: from hormones to genes. Aquaculture 197:99-136.25 EIFAC/ICES. 2001. Report of the EIFAC/ICES Working Group on Eels. Copenhagen, Denmark, 28-31 August 2001.26 FAO. 1996. Aquaculture development and resource limitations in Egypt. FAO Aquaculture Newsletter December 1996, Number 14.http://www.fao.org/fi/newslet/fan14/articl1f.asp27 Kapuscinski, A.R. and D. J. Brister. 2001. Genetic impacts of aquaculture. Pages 128-153 in K.D. Black, ed. Environmental Impacts ofAquaculture. Sheffield Academic Press.28 Guo X.M., and S.K. Allen, 1994. Viable tetraploids in the Pacific oyster Crassostrea gigas (Thunberg) produced by inhibiting polar body I in eggsfrom triploids. Mol. Mar. Bio. Biotechnol., 3:42-50.29 Yamaki M., and Katsutoshi A., 2000. Ploidies of gametes produced by putative tetraploid Amago salmon induced by inhibitionof first cleavage.Bulletin of the Faculty of Fisheries Hokkaido University, 51(3):135-152.30 Rothbard S., W.L. Shelton, I. Rubinstein,Y. Hinits, L. David, 2000. Induction of all female triploids in grass carp Ctenopharyngodon idella byintegration of hormonal sex inversion and ploidy manipulation. Israeli Journal of Aquaculture, 52(4):133-15016


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityIn general, animals produced with such techniquescompete more efficiently ong>forong> resources (food), disruptmating behaviour and success and may affectthe natural stocks. Research is required to elucidatethe potential impacts of such practices.38. Experiments are now under way to producetransgenic fish (genetically modified fish) in orderto enhance perong>forong>mance under growout condition. 31Special care must be taken to prevent broodstocksfrom mixing with wild populations.39. The common practice of transfer of broodstockand fry between different regions of the globecould have an effect on biodiversity through theintroduction of allochthonous species, diseases andother related impacts.40. Effluents from hatcheries are usually rich innutrients and chemical compounds. Recirculatingsystems control water quality and reduce diseaseintroduction. In flow-through systems, a generalpractice is to include a settling pond ong>forong> the treatmentof wast-water beong>forong>e it is returned into theenvironment. Chemicals tend to persist in thewater column and are introduced into natural environments.Regular monitoring of inputs intoaquatic systems must be carried out.Growout41. For most of the major species of finfish, fertilizedeggs are incubated until hatching (a very shortprocess in tropical species, but several months insalmonids) and then conditioned to artificial feedin tanks beong>forong>e transfer to growout facilities (pens,cages, large tanks).42. Cage culture is divided into two main categories:inshore cages and offshore cages, and can beeither floating, fixed or submerged. Inshore cagesare located in protected and usually shallow areaswith generally less water circulation than offshorecages. On the other hand, offshore cages are locatedin deep water and open areas with less protectionfrom storms but with better water exchange.Cage-reared fish are fed supplemental or artificialdiets depending on the stocking density and thelevel of technology applied. 32 In inshore cages, possibleimpacts include water quality degradation,transfer of disease, alteration of the benthic communitybiodiversity, input of antibiotics, antifoulingand other chemicals as well as the risk ofescapes. These impacts can be minimized by theproper management, site selection and continuousmonitoring. In order to reduce potential impacts,clear monitoring parameters must be established.In offshore cages the highest risk results fromescapees. However, total nutrient inputs in the lattercould be similar or even greater than inshoresystems. For both types of cages, nets and mooringsystems provide additional substrate ong>forong> colonization.43. Nets and fish pens are located in shallow, shelteredwaters, and their edges are anchored to thebottom/substrate. In the Philippines, milkfish pensgenerally have a nursery compartment within thegrow-out pen/enclosure. Fish in the nursery compartmentand are not generally given supplementalfeeding except ong>forong> occasional rations of breadcrumbs, rice bran, broken ice cream cones, fishmeal, and ipil-ipil leaf mill. 33 Direct biodiversityimpacts of fish pens involve the disappearance ofbenthic communities over large areas. Strong alterationof hydrodynamics has also been observed.44. A typical fish pond system consists of the followingbasic components: pond compartmentsenclosed by dikes, canals ong>forong> supply and drainage of31 FAO. 2000. The state of the world fisheries and aquaculture 2000. FAO, Rome. ISBN 92-5-104492-9.http://www.fao.org/DOCREP/003/X8002E/x8002e00.htm32 Baluyut, E. A. 1989. Aquaculture systems and practices: a selected review. UNEP/FAO, Rome. ADCP/REP/89/43.http://www.fao.org/docrep/T8598E/t8598e00.htm#Contents33 Ibid.17


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversitywater to and from the pond compartments, andgates or water control structures to regulate entryand exit of water into and from the pond compartments.34 Most mullet farms use shallow ponds andlow stocking densities (less than 1 fish per squaremetre). Milkfish pond culture in the Philippinesfollows a progressive culture scheme, with separate,transition, and rearing ponds. 35 Fish grown in semiintensiveand intensive culture ponds are given supplementaryand full artificial feeds, respectively. 36Large pond systems cause changes in naturalecosystems and have effects on ecosystem diversity.The quality of waste water from ponds depends onthe stocking density, and constant monitoring ofwater quality will ensure the minimization ofimpacts on natural ecosystems.45. Recirculating systems use different levels ofwater inputs. These types of systems are sometimesautomated and include complete water treatmentas well as permanent control of temperature andphysical and chemical parameters. Fish are stockedat high densities and artificial feed is used. Water istreated beong>forong>e it is discharged into the environment.These systems can avoid the negative impactsof other aquaculture systems. However, a proportionof dissolved nutrients are still entering the naturalenvironment. In the case of disease outbreaks,the water can be treated beong>forong>e discharge.Recirculating systems require high initial investmentsand can only be feasible ong>forong> intensive culture.46. Enhancement or ranching is most developedwith marine finfish. This deals with the deliberaterelease of organisms from hatcheries. In enhancement,fry are released in order to restock wild populationswhile in ranching the fish are harvestedfrom artificially enclosed areas. These techniquescould have important impacts on the genetic diversityof wild stocks.5. Echinoderms47. Echinoderms include sea cucumbers and seaurchins, in particular locally important speciesfrom Asia, Australia, and North and South America.Broodstock and seed supply48. Broodstock is collected yearly from wild stocksand spawning is achieved through use of physicalstimulus in laboratory conditions. Urchin larvae aregrown in tanks, and juveniles are released to the sea.Sea cucumber larvae are sometimes collected fromnatural stocks present on seaweeds.Growout49. In general, there are no specific techniques ong>forong>growout. In some cases, intermediate storage ofechinoderms takes place in suspended culture incages, prior to release to natural fishing grounds.C. BIODIVERSITY EFFECTS OF THEMAIN TYPES OF MARICULTURE50. All ong>forong>ms of ong>maricultureong>, regardless of physicalstructure or economic motivation, affect biodiversityat genetic, species and ecosystem levels. At theecosystem level, both goods and services functionscan be affected, with widespread consequences andknock-on long-term effects. Thereong>forong>e, the interconnectednature of aquatic communities requirethat impacts on aquatic ecosystems should be consideredin a holistic manner, both in the short andlong terms. This section presents a summary of themain biodiversity effects of ong>maricultureong>.51. Mariculture can modify, degrade or destroyhabitat, disrupt trophic systems, deplete naturalseedstock, transmit diseases and reduce geneticvariability. For example, coastal mangroves have34 Ibid.35 Ibid.36 Ibid18


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversitybeen converted into shrimp ponds, enclosed orsemi-enclosed waters have been affected by nutrientloading (or stripping), and benthic habitatsaffected by bivalve bottom culture practices as wellas by sedimentation.52. However, ong>maricultureong> could also provide localbiodiversity enhancement under certain circumstances,ong>forong> example birds could be attracted toong>maricultureong> sites 37 and artificial reefs acting asspecies aggregating devices may result in enhancedbiodiversity. In situ coral replanting programmeshave also proved to have a positive effect on reefbiodiversity. 3853. Depending on energy sources used to producebiomass, ong>maricultureong> could be divided into(a) Autochthonous organic-based or “natural”trophic systems, such as kelp culture, and raftculture of mussels or oysters. Such culturepractices derive their energy from solar radiationor nutrient sources already available innatural ecosystems, and tend to have fewernegative effects on biodiversity. In somecases, their impact on biodiversity may evenbe positive;(b) Allochthonous organic-based or “artificial”trophic systems, such as net and pond cultureof fish and shrimps, derive energy mainlyfrom feeds supplied by growers and are morelikely to disrupt the natural ecosystems.54. All the environmental effects are stronglydependent on the sensitivity of a particular ecosystem,or its type. Thus, some wetland habitats andecosystems are particularly vulnerable, such asthose that have been identified as threatened orsensitive, either due to their rarity or their vulnerabilityto change. Such ecosystems include mangroves,estuaries, seagrass beds, coral reefs as well asspecific benthic communities. Specific impacts willdepend on different carrying capacity requirementsong>forong> various culture practices in any givenecosystem, which however are poorly known.55. Culture systems in open waters discharge theirnutrient rich wastes (faeces and uneaten feed)directly into the water and could cause increases introphic status. Semi-enclosed ecosystems such assheltered bays are particularly sensitive to sucheffects. This may lead to blooms of phytoplankton,including toxic species, and their consequentdegradation can drastically reduce oxygen levels.Algal blooms can also cause severe shading ofseafloor vegetation that serves as nursery habitatand refuge ong>forong> finfishes and benthic invertebrates. 39In sheltered bays the effects of such waste sedimentationon the sea bottom tend to be confined towithin 50 or 100 meters of the site. However, inbays swept by strong currents the nutrients mayspread widely and spark algal blooms within days 40 ,although Beveridge 41 and Gowen and Bradbury 42report that strong tidal currents tend to dilutewastes beong>forong>e they can cause hypernutrification oreutrophication. Both effects are culture densitydependent.43 44 Scallops and oysters, ong>forong> example, individuallyproduce up to 50~60g and 120g faeces indry weight respectively each year. 45 Some of this37 Davenport, J., K. Black, G. Burnell, T. Cross, S. Culloty, S. Ekaratne, B. Furness, M. Mulcahy and H. Thetmeyer. 2003. Aquaculture: The EcologicalIssues, by Malden, MA, British Ecological Society/Blackwell Science, 89p.38 Ekaratne, personal communication.39 Bricelj, V. M., and D. J. Lonsdale. 1997. Aureococcus anophagefferens: causes and ecological consequences of brown tides in U.S. mid-Atlanticcoastal waters. Limnology and Oceanography 42:1023-1038. Cited in Smith.40 Silvert, W. Spatial Scales of Mariculture Impacts. Habitat Ecology Division From a paper presented at a workshop in Bergen, to be published inFisken og Havet. Available at: http://www.mar.dfo-mpo.gc.ca/science/mesd/he/staff/silvert/scales.html.41 Beveridge, M. C. M. 1996. Cage aquaculture, 2nd Ed. Fishing News Books, Oxong>forong>d.42 Gowen, R. J., and N. B. Bradbury. 1987. The ecological impact of salmon farming in coastal waters: a review. Oceanorg. Mar. Biol.Rev. 25:563-575.43 Ibid.44 Wu, R. S. S., K. S. Lam, D. W. MacKay, T. C. Lau, and V. Yam. 1993. Impact of marine fish farming on water quality and bottom sediment: a casestudy in the sub-tropical environment. Marine Environmental Research 38:115-45.45 Tang, Q., and J. Fang. Impacts of intensive ong>maricultureong> on coastal ecosystem and environment in China and suggested ong>sustainableong> managementmeasures. Yellow Sea Fisheries Research Institute, Qingdao, 266071. http://www.aquachallenge.org/abstracts/tang.html19


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversity58. The organophosphate class of chemicals likedichlorvos and trichlorphon used outside theUnited States of America to control sea lice (parasitecopepods that feed on salmonid mucus)includes nerve gases and many insecticides. Effectson the marine environment are not well studied,though are usually assumed to be negative.However, supporters of the use of the carbamateinsecticide Sevin to kill burrowing shrimp (whichundermine intertidal zone sediments used ong>forong> oysterbeds) believe that by stabilizing sediments theinsecticide promotes greater biological diversity.59. Chemicals are also used as antifouling agentsand as disinfectants. Antifoulants such as TBT arebanned in developed countries ong>forong> aquaculturepurposes, but are still used in some other countries,where they continue to impact on biodiversity.Sandnes and Ervik 51 report that as salmon productionin Norway has increased the relative usage ofantifoulants has declined, with the exception ofcopper, which rose from 119 tonnes in 1991 to 174tonnes in 1995.60. Hormones are used to induce or prevent reproductivematuration, ong>forong> sex reversal and to promotegrowth. Bath and feed-incorporated applications ofhormones are obviously more of a concern thancontrolled injection into individual broodstockanimals because they become readily released intosurrounding waters where they can persist in theenvironment or in aquaculture products. Hormoneuse is not well documented and is sometimes carriedout without adequate understanding of thequantities needed.61. Parasites in cultured stock pose problems notonly ong>forong> aquaculturists but also ong>forong> other organismsin the environment. In British Columbia, ong>forong> example,one theory ong>forong> the rise of Parvicapsula infectionin migrating Pacific salmon is acquisition froma fish farm. The parasite is suspected to be linked toprofound changes in migratory behaviour ofsalmon that leads to massive pre-spawning mortalityand may be responsible ong>forong> decimation ofdiversity at the population level. 5262. While there is a welcome trend in capture andculture fisheries management to consider harvestedspecies as part of an ecosystem rather than “standalone”targets, the effects of ong>maricultureong> on aquaticecosystems have been little studied. Given the scaleof culture of some of the major species, the effectson the different hierarchical levels of biodiversitycan be far-reaching.63. The high value marine carnivorous species thatare farmed require feeds incorporating animalsources of proteins. The most obvious effect offarming these carnivorous species such as salmon,trout, and sea bream is that more protein is fed tothe fish than is later harvested ong>forong> human consumption.Most of this feed comes from marinesources in the ong>forong>m of fish meal and fish oils, andthe percentage of fish meal incorporated into fishfeed has been increasing from 10% in 1988, to 17%in 1994 to 33% in 1997. 53 However, a large proportionof fish meal is also diverted to pig and poultryfeeds. The fish meal industry, partly driven by globaldeficits in fish oils 54 , is actively seeking plant proteinreplacements. Fish protein and lipids presentlycome from large fisheries ong>forong> small pelagic fish, suchas anchoveta, Chilean jack mackerel and Atlanticherring. These fisheries comprise four of the fivetop global fisheries. Although plant proteins are51 Sandnes, K., and A. Ervik. 1999. Industrial marine fish farming. Pages 97-107 In N. Svennevig, H. Reinertsen, and M. New (eds.). Sustainableaquaculture: food ong>forong> the future? A. A. Balkema, Rotterdam. 348 pp.52 C.Wood, personal communication 2002.53 Davenport, J., K. Black, G. Burnell, T. Cross, S. Culloty, S. Ekaratne, B. Furness, M. Mulcahy and H. Thetmeyer. 2003. Aquaculture: The EcologicalIssues, by Malden, MA, British Ecological Society/Blackwell Science, 89p.54 Sandnes, K., and A. Ervik. 1999. Industrial marine fish farming. Pages 97-107 In N. Svennevig, H. Reinertsen, and M. New (eds.). Sustainableaquaculture: food ong>forong> the future? A. A. Balkema, Rotterdam. 348 pp.21


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversitybeing developed ong>forong> inclusion as protein sources infish feeds, complete replacement of fish oils in fishmeals may not be possible since they have a beneficialeffect on in resistance against fish diseases.64. Harvesting small fish ong>forong> conversion to fishmeal leaves less in the food web ong>forong> other commerciallyvaluable predatory fish, such as cod, and ong>forong>other marine predators, such as seabirds and seals.Pauly et al. 55 56 identified a significant trend in aquacultureof “farming up the food chain” that theyconsider in combination with the global problemof “fishing down the food chain”. However, thisstatement continues to attract debate. 57 Increasingintensification of aquaculture, especially in Asia,and its concentration on higher-value carnivorousspecies, is inexorably raising dependence on capturefisheries through increased feed production.The competitive nature imposed on marine fisheriesby culture fisheries merits further investigation.65. Bivalve culture takes nutrients away from themarine food web, but only affects biodiversityadversely if the carbon and nitrogen removed fromthe water column becomes excessive, leaving lessong>forong> other herbivores and phytoplankton, therebyaffecting the growth and reproduction of zooplanktonand other herbivorous marine animals. 58Bivalves do take suspended seston (particulate mattersuspended in water) and change it into denserparticles that fall to the bottom. 59 Permanent extensivebivalve culture may bring about changes in thecoastal food web 60 61 causing eutrophication.66. The loss or alteration of habitat becomes a biodiversityeffect when it changes living conditionsong>forong> other species. Seed collection from habitatssuch as lagoon bottom habitats using destructivegear results in habitat destruction or/and alteration.Mariculture takes up space, often very largeamounts of it, not only in bays and oceans but alsoon nearby ong>forong>eshores. The sheer occupying of acresof water can affect migratory routes and feedingpatterns of a wide variety of non-target species.Salmon farms, ong>forong> example, are believed by some tointerrupt the free movement of wild migratingsalmon and feeding killer whales. 62 Underwaterexploders and other acoustic devices intended todeter predators may also increase the stress on nontargetanimals.67. Converting tidal wetlands ong>forong> shrimp pondsand building roads, dikes, and canals threatensbenthic habitat diversity in the tropics, particularlyin Latin America and Asia. 63 Tidal marshes andmangroves that serve as nursery grounds ong>forong> wildshrimp and fish populations are lost, and less mangroveand marsh grass detritus enters coastal foodwebs. 64 The draining of ponds ong>forong> harvest releases55 Pauly, D., V. Christensen, J. Dalsgaard, R. Froese, and F. Torres, Jr. 1998. Fishing down marine food webs. Science 279:860-863.56 Pauly, D., R. Froese, L. Y. Liu, and P. Tyedmers. 2001. Down with fisheries, up with aquaculture? Implications of global trends in the meantrophic levels of fish. Presented at AAAS-sponsored mini symposium The Aquaculture Paradox: Does Fish Farming Supplement or DepleteWorld Fisheries, 18 February, 2001. San Francisco. 12 p.57 Tidwell, J.H. and G. L. Allan. 2001. Fish as food: aquaculture's contribution. Ecological and economic impacts and contributions of fishfarming and capture fisheries EMBO reports 2: 958-96358 Tang, Q., and J. Fang. Impacts of intensive ong>maricultureong> on coastal ecosystem and environment in China and suggested ong>sustainableong> managementmeasures. Yellow Sea Fisheries Research Institute, Qingdao, 266071. http://www.aquachallenge.org/abstracts/tang.html59 Grant, J. 1999. Ecological constraints on the sustainability of bivalve aquaculture. In N. Svennevig, H. Reinertsen, and M. New (eds.). Sustainableaquaculture: food ong>forong> the future? A. A. Balkema, Rotterdam. 348 pp.60 Horsted, S. J., T. G. Nielsen, B. Riemann, J. Pock-Steen, and P. K. Bjornsen. 1988. Regulation of zooplankton by suspension-feeding bivalves andfish in estuarine enclosures. Mar. Ecol. Prog. Ser. 48:217-224.61 Tenore, K. R., L. F. Boyer, R. M. Cal, J. Corral, C. Garcia-Fernandez, N. Gonzalez, E. Gonzalea-Gurriaran, R. B. Hanson, J. Iglesias, M. Krom, E.Lopez-Jamar, J. McClain, M. M. Pamatmat, A. Prez, D. C. Rhodas, G. deSantiago, J. Tietjen, J. Westrich, and H. L. Windom. 1982. Coastalupwelling in the Rias Bajas, NW Spain: contrasting the benthic regimes of the Rias de Arosa and de Muros. J. Mar. Res. 40:701-772.62 Morton, A. B., and H. K. Symonds, 2002. Displacement of Orcinus orca (L.) by high amplitude sound in British Columbia, Canada. ICES Journalof Marine Science 59:71-80.63 Smith, C. 2000. Global Change and Biodiversity Linkages across the Sediment-Water Interface. Bioscience. Full article available at:www.bioscience.org64 Naylor, R. L., R. J. Goldburg, J. H. Primavera, N. Kautsby, M. C. M. Beveridge, J. Clay, C. Folke, J. Lubchenco, H. Mooney, and M. Troell. 2000.Effect of aquaculture on world fish supplies. Nature 405:1017-1024. Cited in Smith.22


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversitydiseases, antibiotics, and nutrients into estuarineand coastal waters. Despite the possibly large-scaleimplications, the effects in the coastal zone remainpoorly studied. 65 Conversion of new habitats ong>forong>brackish-water prawn farming by the transport ofsalt water to inland ponds, as well as conversion ofproductive rice growing areas to prawn ponds,changes their associated biodiversity.68. The best-known example of habitat alterationarising from ong>maricultureong> is the effect of shrimpfarming on mangrove ecosystems, which have veryhigh species diversity both in the water and on landand contribute about one-third of yearly landingsof wild fish in South East Asia. Abandoned shrimpponds serve as a threat to contiguous coastal habitatsand their biodiversity.69. The local or more widespread effects on nontargetspecies such as the by-catch of seed collectionfrom the wild have not been well studied. Inculture systems where there are no methods ong>forong>artificial control of reproduction, or where suchmethods exist but are beyond the means of localfarmers, manual collection of fry ong>forong> growout canremove significant amounts of biomass and biodiversity.For example, the collection of one tigershrimp larva involves the removal of 1400 othermacrozooplankton individuals. 66 Naylor et al. 67 reviewthe effects of fry collection on natural seedstock,noting that 85% of the larvae collected ong>forong> milkfishfarming in the Philippines, ong>forong> example, are fromspecies other than milkfish, and are discarded - asignificant bycatch. Although hatchery reproductiontechniques are available ong>forong> some species, inpoorer areas where hormonal or environmentalmanipulation of broodstock is impossible, wild fryare still resorted to.70. In net-pen culture, crowded and stressful conditionsfrequently lead to outbreaks of infection.Sometimes the infections result from organismsnaturally present in wild fish; in other cases, thedisease organism is an exotic one. Salmon net-penfarming provides an example of the spread of exoticpathogens. 68 In 1985, a virulent strain of the bacteriumAeromonas salmonicida, which causes thedisease furunculosis, was believed to have beenbrought from Scotland to Norway, 69 spreading tosalmon farms and thence to wild salmon andkilling large numbers of fish. 70 Bivalve and shrimpfarming can also cause disease transmission. Wildbroodstock of Pacific white shrimp (Penaeus vannamei)infected with white spot disease (WSSV)have been moved to previously disease-free regions 71while Taura Syndrome, caused by the TSV virus,may have been spread through shrimp cultures inLatin America by the transfer of diseased postlar-65 Smith, C. 2000. Global Change and Biodiversity Linkages across the Sediment-Water Interface. Bioscience. Full article available at: www.bioscience.org66 Davenport, J., K. Black, G. Burnell, T. Cross, S. Culloty, S. Ekaratne, B. Furness, M. Mulcahy and H. Thetmeyer. 2003. Aquaculture: The EcologicalIssues, by Malden, MA, British Ecological Society/Blackwell Science, 89p.67 Naylor, R. L., R. J. Goldburg, J. H. Primavera, N. Kautsby, M. C. M. Beveridge, J. Clay, C. Folke, J. Lubchenco, H. Mooney, and M. Troell. 2000.Effect of aquaculture on world fish supplies. Nature 405:1017-1024. Cited in Smith.68 Kent, M. L. 1994. The impact of diseases of pen-reared salmonids on coastal marine environments. Pages 85-95 In A. Ervik, P. Kupka, P. Hansen,and V. Wennevik (eds.). Proceedings of the Canada-Norway workshop on environmental impacts of aquaculture. Bergen, Norway: NorwegianInstitute of Marine Research. Cited in Ellis and Associates (1996). Cited in Goldburg.69 Munro, A. L. S. 1988. Advantages and disadvantages of transplantations. Pages 75-83 In E. Grimaldi, and H. Rosenthal (eds.). Efficiency in aquaculture production: disease control. Proceedings of the 3rd Annual International Conference on Aquafarming “AQUACOLTURA ’86,” Verona,Italy. Edizioni del Sole 24 Ore, Milan, 227 pp. Cited in Goldburg.70 Heggberget, T. G., B. O. Johnsen, K. Hindar, B. Jonsson, L. P Hansen, N. A. Hvidsten, and A. J. Jensen. 1993. Interactions between wild and cultured Atlantic salmon: a review of the Norwegian experience. Fisheries Research 18:123-146. Cited in Goldburg.71 Wang, Y. L. 1999. Utilization of Genetic resources in Aquaculture: A farmer’s view ong>forong> ong>sustainableong> development. R. S. V. Pullin, D. M. Bartley, andJ. Kooiman (eds.). Towards policies ong>forong> conservation and ong>sustainableong> use of aquatic genetic resources. ICLARM Conf. Proc. 59. 277 pp.72 Lightner, D. V. 1999. The Penaeid shrimp viruses TSV, IHHNV, WSSV, and YHV: current status in the Americas, available diagnostic methods,and management strategies. Journal of Applied Aquaculture 9(2):27-52.23


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityvae and broodstock. 72 The impact of this introducedvirus on its recipient environment is still73 74unknown. The Japanese oyster drill (Ocenebrajaponica) and a predatory flatworm(Pseudosylochus ostreophagus) were brought toAmerican waters along with the Pacific oyster, nowthe mainstay of bivalve farming in North America.However, these parasites have contributed to thedecline of native West Coast oyster stocks. 75 Thecase of MSX in the USA, Bonamia in Europe providefurther examples of poorly managed aquaculturepractices. However, a considerable amount ofguidelines and legislation relating to disease regulationand control have been developed, such as thoseof the International Council ong>forong> Exploration of theSeas (ICES), Network of Aquaculture Centres inAsia-Pacific (NACA), Food and AgricultureOrganization (FAO), and European Inland FisheriesAdvisory Commission (EIFAC).71. The genetic effects of ong>maricultureong> are variedand highly significant ong>forong> biodiversity. Unlike manyof the other effects discussed so far, understandinggenetic effects demands a high level of understandingof the genetic structure of both the farmed andwild populations, something we do not have ong>forong>any species. The field of fish molecular genetics isjust starting to expand rapidly as new analyticaltechniques become available. For now, predictingthe genetic effects of ong>maricultureong> will remain difficult,and many prognostications may turn out to bewrong. The genetic effects of cultured marine animalsare either inadvertent (through escapes of culturedanimals) or deliberate (enhancement or searanching).72. Studies of hatchery populations suggest that76 77such loss of genetic diversity is common (ong>forong> fishand ong>forong> invertebrates). 78 79 Such reduced interpopulationvariation is not necessarily bad ong>forong> culturedpopulations, but can have a long-term impact onspecies survival if the farmed stocks intermingle80 81with wild neighbours. This situation occurswhen the species being farmed is a local one, andmight be called “inadvertent enhancement”. It isbest studied in salmon aquaculture. It is knownthat the use of a smaller number of individuals ong>forong>breeding programmes would result in inbreeding,crossing of two or more locally adapted populationsleads to outbreeding depression because ahigh level of local adaptation occurs in each population.Though this outbreeding depression usuallydoes not affect fitness in the first generation ofprogeny, subsequent progeny generations areaffected by a reduction in fitness, as has beendemonstrated with Pacific salmon in one recentstudy. 82 The escape of fertile hybrids of closelyrelated species that is being presently being carriedout in sturgeon breeding programmes could bringabout genetic changes, the effects of which are yetunknown. Another undesirable effect on biodiversityat the genetic level could be the loss of co-adaptedgene complexes through repeated inbreeding.73 Boyd and Clay, 1999. cited in Wang 1999.74 Flegel, T. 1998. Shrimp disease epizootics: significance of international pathogen transfer. Pages 51-52 In Regional programme ong>forong> the development of technical guidelines on quarantine and health certification, and establishment of inong>forong>mation systems, ong>forong> the responsibility movementof live aquatic animals in Asia. TCP/RAS/6714. Field Doc. No. 1. FAO/NACA/OIE, Bangkok.75 Clugston, J. P. 1990. Exotic animals and plants in aquaculture. Reviews in Aquatic Sciences 2(3,4):481-489. Cited in Goldburg.76 Verspoor, E. 1988. Reduced genetic variability in first generation hatchery populations of Atlantic salmon (Salmo salar). Canadian Journal ofFish and Aquatic Science 45:686-690. Cited in Smith 1999.77 Koljonen, M. L. 1989. Electrophoretically detectable genetic variation in natural and hatchery stocks of Atlantic salmon in Finland. Hereditas110:23-35. Cited in Smith 1999.78 Durand, P., K. T. Wada, and F. Blanc. 1993. Genetic variations in wild and hatchery stocks of the black pearl oyster Pinctada margaritifera fromJapan. Aquaculture 110:27-40. Cited in Smith 1999.79 Benzie, J. A. H., and S. T. Williams. 1996. Limitations in the genetic variation of hatchery produced batches of giant clam Tridacna gigas.Aquaculture 139:225-241. Cited in Smith 1999.80 Ibid.81 Gharrett, A. J., and W. W. Smoker. 1993. A perspective in the adaptive importance of genetic infrastructure in salmon populations to oceanranching in Alaska. Fis. Res. 18:45-58. Cited inSmith 1999.82 Davenport, J., K. Black, G. Burnell, T. Cross, S. Culloty, S. Ekaratne, B. Furness, M. Mulcahy and H. Thetmeyer. 2003. Aquaculture: The EcologicalIssues, by Malden, MA, British Ecological Society/Blackwell Science, 89p.24


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversity73. The production of sterile fish is often advancedas a mitigating technology. However, although sterilefish cannot establish wild populations or interbreedwith wild fish, they can still compete withwild fish ong>forong> food, spread disease, and disturb wildnesting sites. Escaped or released fertile tetraploidsmay attempt to breed with wild fish and disruptoverall spawning success. Gene transfer (not yetused in commercial ong>maricultureong>) may have ecologicaleffects if the introduced DNA causes majorchange in the ecological role of the transgenic fish(by, ong>forong> example, increasing its size or its ability touse new food sources). Transgenic fish given a geneto speed growth, ong>forong> example, could out-competewild fish ong>forong> food or spawning sites, while fish engineeredong>forong> cold-tolerance might intrude on theranges of more northerly species. Unanticipatedpleiotropic (multiple) effects may also appear.74. Most animals farmed on land are highlydomesticated, and without human protection theywould likely fail to survive in the wild. Organismsused in aquaculture on the other hand are still relativelywild, and may easily survive and reproduceoutside their natural ranges. 83 Because much of theworld’s aquaculture relies on species outside theirnative range, escapes are a constant biodiversityconcern. In the short term, escapes of hatcheryspecies may swamp wild populations through sheerweight of numbers. Skaala 84 stated that the numberof Atlantic salmon (Salmo salar) escaping fromfish farms in Norway exceeded the number of wildfish harvested in Norway. 85 A comparison of wildand farmed Atlantic salmon showed that farmedfish had higher growth rates and were more aggressivethan wild fish, thus posing a threat to nativepopulations that were already depleted by environmentalfactors. 8675. Many alien marine species resulting fromescaped cultured stocks have become firmly establishedfar from their native ranges and are culturallyaccepted as “just more biodiversity”. However,when self-sustaining populations of escapesbecome established, they could interact with nativecommunities in a number of ways, including predation,competition and even elimination of nativespecies. Japanese oyster and Manila clam, ong>forong> example,are treasured by recreational fishermen on thePacific coast of North America as well as in Europe.The risk is probably greater with escape of speciesoccupying similar niches to local ones, because theyare more likely to interact with native populationsand affect their survival. The ability of natural populationsto recover from introgression of farmedgenes has been very little studied.83 Courtenay, W. R., Jr., and J. D. Williams. 1992. Dispersal of exotic species from aquaculture sources, with emphasis on freshwater fishes. Pages49-81 In A. Rosenfield, and R. Mann (eds.). Dispersal of living organisms into aquatic ecosystems. College Park, MD: Maryland Sea GrantCollege, University of Maryland. Cited in Goldburg.84 Skaala, O. 1995. Possible genetic and ecological effects of escaped salmonids in aquaculture. Pages 77-86 In Environmental impacts of aquaticbiotechnology. OECD, Paris. Cited in Penman 1999.85 Penman, D. J. 1999. Biotechnology and aquatic resources: genes and genetically modified organisms. Pages 23-33 In R. S. V. Pullin, D. M. Bartley,and J. Kooiman (eds.). Towards policies ong>forong> conservation and ong>sustainableong> use of aquatic genetic resources. ICLARM Conf. Proc. 59. 277 pp.86 Einum, S. and I. A. Fleming. 1997. Genetic divergence and intyeractions in the wild among native, farmed and hybrid Atlantuc salmon.Journal of Fish Biology 50:634-651. Cited in Smith 1999.25


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversity3. AVOIDING THE ADVERSE EFFECTS OF MARICULTUREON MARINE AND COASTAL BIODIVERSITY76. While ong>maricultureong> has a variety of adverseeffects on biodiversity, many of these effects can bemitigated or eliminated. In some cases, it is evenpossible to produce some positive biodiversityrelatedeffects. It is important to mention that ong>maricultureong>based on allochthonous feed (most finfishand crustaceans) could have larger and more significantadverse effects than ong>maricultureong> based onauthochthonous feed (filter feeders, macroalgae,deposit feeders). The areas offering the most promiseong>forong> avoiding adverse biodiversity effects of ong>maricultureong>include reducing waste by better management,changes in nutrition (reong>forong>mulation offeeds, reduction in use of animal protein, improvingutilization) and technological improvementssuch as “enclosed systems”. In such enclosedtanks or ponds, it is possible to treat the effluent inorder to avoid outflow of chemicals, antibiotics, diseases,as well as excess nutrients. Annex II belowdescribes problems, impacts, main mitigation tools,and the results of mitigation.77. Better management practices ong>forong> non-enclosedsystems, include:(a) Most importantly, proper site selection. Thelocation of cages, pens, rafts, etc., shouldensure proper water circulation to satisfyboth the needs of ong>maricultureong> and the flushingof nutrients and wastes;(b) Secondly, optimal management, includingproper feeding to decrease conversion ratios.Proper feeding requires proper training and agood knowledge of the behaviour of organismsto be fed. Often workers feeding finfishor crustaceans have poor knowledge of whatthey do, and the basis of feeding practices.This is true in particular in developing countries.It should be noted that cheap labouroften works against biodiversity simplybecause the lack of proper managementknowledge and training investment.78. Other mitigation measurements include culturingdifferent species together (polyculture)to make better use of available resources (such assalmon and bivalve culturing or salmon andmacroalgae) and coupling ong>maricultureong> with otheractivities such as artisanal fisheries and sport fishing.However, all such ong>forong>ms of mitigation are87 88effective only if chemicals and antibiotics are avoidedin intensive production.79. Enclosed, and especially re-circulating systemsrequire, ong>forong> many ong>forong>ms of aquaculture, hightechnological development and capital investment,making the use of such technology impossible ong>forong>many species and countries. However, future developmentof ong>maricultureong> should proceed in thisdirection in order to minimize impacts of everykind. This is particularly true ong>forong> the production offin fish and crustaceans.80. Other impacts such as dependence on wildseed, reducing the use of chemical additives andtreatments that promote ecosystem changes, andreducing disease transmission between culturedand wild stocks can be avoided with better managementpractices and other technologicalimprovements, which are discussed here in moredetail. For all of the ong>forong>egoing strategies, developmentof appropriate policies and legislation is anoverarching necessity. Responsible ong>maricultureong>(codes of conducts, licence permits), policies andregulation should reinong>forong>ce mitigation measurements.81. Mariculture could also be considered as havingpositive effects when, under certain circumstances,it provides seed ong>forong> sea-ranching and recovery ofwild stocks, endangered species, or even improvesproductivity and biodiversity.87 Soto, D. and F. Jara. 1999. Relevance of Ecosystemic services provided by species assemblages: coupling salmon farming with biodiversity useand management. 1999. In: Schei, Sandlund and Stran (Eds), Norway/UN Conference on the ecosystem approach ong>forong> ong>sustainableong> use of biodiversitypp 133-137.88 Soto, D. and F. Jara Using natural ecosystemic services to diminish salmon farming foot –print in southern Chile. In T. Berth (Editor).“Ecological and genetic Implications of Aquaculture Activities”. Kluwer Acad. Press. Accepted.26


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityA. BEST SITE SELECTIONAND BETTER MANAGEMENTTO REDUCE NUTRIENTINPUT EFFECTS82. Proper site selection is usually the best tool ong>forong>management and mitigation of nutrient inputs tothe environment. In some cases such nutrientinputs could have positive effects on local productivityand biodiversity. The key issue is not to allownutrients to be lost to bacterial degradation but toenter natural food webs or artificial food webs inthe case of polyculture.83. Mathematical modelling can help estimate therelative impacts of a ong>maricultureong> operation. Forsuch modelling however, basic inong>forong>mation, such asestimates of other nutrient inputs to bodies ofwater, is often hard to find. 89 Cooperation withother sectors is needed. Types of mathematicalmodels include mass balance models and hydrologicalmodels ong>forong> siting, as well as the use of geographicinong>forong>mation systems (GIS) tools. In addition,the application of integrated marine andcoastal area management (IMCAM) can help optimizespatial distribution and help mitigate theeffects of ong>maricultureong>. Examples include modelsdeveloped ong>forong> the coast of Norway 90 and ong>forong> mostlakes with salmon farming in Chile. 9184. The use of enclosed or recirculating systems isan option when no others are available and whenmonitoring programs show a negative environmentaleffect or an overloaded carrying capacity inrelation to nutrients. Replacing net pens with bagssuspended in seawater has been endorsed as anoption, which also helps avoid the escape of exoticspecies; however, the initial capital outlay is higher. 92Nevertheless, closed systems offer much better controlof feeding and better flesh quality due toincreased exercise, and are slowly becoming established(www.futuresea.com). Since netpens externalizecosts to the environment, future policy andregulations that impose environmental penaltieson such systems may help the development ofaquaculture systems that produce less waste. 9385. Waste can also be reduced by improved filtrationand fallowing. Technological means of collectingsuspended solids include biofilters that transong>forong>mexcreted nitrogen into nitrite, nitrate, andfinally nitrogen gas. 94 In Australia, a study of submergedflow biofilter systems built in modularong>forong>m showed complete denitrification of fish farmwaters could be achieved, with approximately 40percent of the phosphorus removed as well. 95Shutting down ong>maricultureong> sites ong>forong> months oryears can allow accumulated nutrients to breakdown or disperse. 9686. Large shellfish culture beds may lead toincreased excess sediment accumulation. This ismainly due to the biodeposit production by shellfish,which are silting underneath rearing structures.Since bivalves feed on natural material carriedby the water column, there is no net additionof organic matter into the environment, althoughparticle density changes. This organic matter accumulationmay result in potential eutrophication89 Pillay, T. V. R. 1992. Aquaculture and the environment. Cambridge, MA: Fishing News Books, 191 pp. Cited in Goldburg.90 Ervik, A, P. K Hansen, J. Aure, P. Johannessen and T. Jahsen. 1997. Regulating the local enviromental impact of intensive marine fish farming I.The concept of the MOM system. Aquaculture 15: 85-94.91 Soto, D. 2000. Situación actual de los efectos ambientales de la salmonicultura en el mundo y en Chile. Documento de investigación bibliografica. Salmón Chile Santiago: 62 p.92 British Columbia Environmental Assessment Office. The Salmon Aquaculture Review Final Report. ISBN 0-7726-3317-7 (set).http://www.eao.gov.bc.ca/project/aquacult/salmon/report/final/vol1/toc.htm93 Goldburg, R., and T. Triplett. 1997. Murky waters: environmental effects of aquaculture in the US. The Environmental Defense Fund. 197 pp.Available at: http://www.environmentaldefense.org/pdf.cfm?ContentID=490&FileName=AQUA.PDF94 Ackeong>forong>s, H. 1999. Environmental impacts of different farming technologies. Pages 145-169 In N. Svennevig, H. Reinertsen, and M. New (eds.).Sustainable aquaculture: food ong>forong> the future? A. A. Balkema, Rotterdam. 348 pp.95 Abeysinghe, D. H., A. Shanableh, and B. Rigden. 1996. Biofilters ong>forong> water reuse in aquaculture. Water Science and Technology 34(11):253–260.IWA Publishing . Abstract and link to full article available at: http://www.iwaponline.com/wst/03411/wst034110253.htm96 Pillay, T. V. R. 1992. Aquaculture and the environment. Cambridge, MA: Fishing News Books, 191 pp. Cited in Goldburg.27


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversitywith biodiversity losses on the bottom. By way ofexample, this accumulation maximizes the developmentof certain seafloor benthic biota, such asbacteria and deposit feeding species. To address thisissue, improved site selection represents an efficientmitigation process, considering the local carryingcapacity, and the capacity of the benthos to processorganic matter. The hydrodynamics of the siteshould be appropriate in order to limit local siltation.Similarly, the rearing structures should facilitatehydrodynamics. By using these mitigationtechniques, a reduced effect on local benthic biodiversityis expected, as well as recovery of pelagiccommunities and improvements in ecosystem97 98 99processes.B.87. Extensive, large scale shellfish ong>maricultureong> maylead to a high stocking biomass and filter feedingcapacity, impacting other herbivores, and the primaryproduction of the water column. Overstockingresults in decreased planktonic biomass, and a qualitativeand a quantitative shift in pelagic communities,and thereong>forong>e food webs. Improving site selectionand establishing thresholds ong>forong> stocking biomassbased upon a sufficient primary productivityto sustain filter feeding represents an efficient mitigationprocess. Similarly, selecting species or/andstrains can reduce pressure on phytoplankton biomass100 101 102production.REDUCING WASTEBY BETTER MANAGEMENT88. The degree of impact from effluent wastes isdependent on husbandry parameters, includingspecies, culture method and feed type, as well as onthe nature of the receiving environment in terms ofphysics, chemistry and biology. 103 Waste frommarine fish farms can contain high concentrationsof organic and inorganic nutrients. It is clear that inthe case of culture methods which involve the useof fishmeal-based feeds, there will be a transfer ofnutrients into the receiving waters (as well as originalnutrient ratios) that may have the potential tolead to increases in nutrient concentrations andultimately to eutrophication. Euthrophication isdefined as “an increase in rate of supply organicmatter to an ecosystem”. 104 Whether euthrophicationwill occur as a consequence of nutrient additionwill depend on the state of the receiving environmentwhich may vary spatially, over short timescalesor seasonally, depending on which factorslimit primary production. 105Improving efficiency of feeding process89. Minimizing the input of nutrients can beachieved by improving the efficiency of food conversion.This can be done through improving feedong>forong>mulations, resulting in better palatability and97 Heral M, 1990. Traditional oyster culture in France. Aquaculture, V.1, Barnabe Ed., Bases biologiques Lavoisier, Tec.&Doc., 342-387.98 Rice M.A., A. Valliere, M. Gibson, A. Ganz, 2000. Ecological significance of the Providence river quahogs:poulation filtration. Journal of Shellfishresearch, 19, 1:580.99 Lenihan, H.S. 1999. Physical-biological coupling on oyster reefs: how habitat structure influences individual perong>forong>mance. EcologicalMonographs 69:251-275.100 Burnell G., P. Goulletquer, S. Stead, 2001. Aquaculture and its role in Integrated Coastal Zone Management. EAS, Conference, Oostend Belgium,April 19-21, 2001. Summary document, 34p.101 Goulletquer P. and M. Héral, 1997. History, present conditions and future of the Molluscan fisheries of North America and Europe. MarineMolluscan production trends in France: from fisheries to aquaculture. Marine Fisheries Review, NOAA Technical Report NMFS, 129:137-164102 Heral M, 1990. Traditional oyster culture in France. Aquaculture, V.1, Barnabe Ed., Bases biologiques Lavoisier, Tec.&Doc., 342-387.103 Wu, R.R.S. 1995 The environmental impact of marine fish culture – towards a ong>sustainableong> future. Marine Pollution Bulletin 31: 159 – 166104 Nixon, S.W. 1995 Coastal marine eutrophication: a definition, social causes and future concerns. Ophelia 41: 199 – 219.105 Black, K.D. 2001 Sustainability of aquaculture In “Environmental Impacts of Aquaculture” (Black, K.D. ed.) Sheffield Academic Press, pg. 199 –21228


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityuptake and by reduction in food wastage.Minimizing effects could also be achieved by usingsome efficient strains of fish, shellfish etc.90. Reduction in the input of waste feed can beachieved through a variety of methods including:use of acoustic detectors in marine cages to reduceloss of feed pellets, use of sensors that detect whenfish reduce feeding activity, linked to input controllersas well as through the use of systems ong>forong>collection and recovery of waste feed.91. Raising the awareness of farm workers to theeffects, both environmental and economic, of feedwastage, and training in efficient hand feeding cancontribute to a reduction in feed usage where automatedand controlled feeding systems are not available.92. In the case of Atlantic salmon production, feedconversion ratios (FCRs) have been improvingcontinuously in the past decades as feeds haveincreasingly become tailored to the dietary needs ofcultured species and as feed wastage has beenreduced due to economic, and to some extent, environmentalpressures. Ennel 106 reported that themean FCR in the Nordic area in 1976 was 2.08 buthad fallen to 1.25 inn 1994 and was further reducedto 1.25 in 1995. Similar reductions in FCRs have beenreported from other salmon producing countries.Reduction of nitrogen and phosphorus in diets93. Nitrogen is generally assumed to be the nutrientlimiting phytoplankton growth in marinewaters. Minimizing the direct input of nitrogenouswastes to the environment from finfish farms canthus minimize potential eutrophication effects.Hall et al 107 found that 67 - 80% of the nitrogenadded to cage system is lost to the environment.The majority (50 - 60% of the total nitrogen) is lostin dissolved ong>forong>m, either directly from the fish or bybenthic flux from solid waste beneath the cages.The level of nitrogen in feeds has decreased as feedong>forong>mulation becomes closely aligned with thedietary requirements of the fish. In particular,modern diets tend to contain more lipid and lessprotein which has contributed to a general reductionof food conversion ratios and a reduction ininputs of nitrogenous waste.94. In the last twenty years the feed conversionratio ong>forong> Norwegian salmon feeds has been cut byabout half, resulting in 80% fewer solids being dischargedfrom salmon farms. 108 From 1974 to 1994,Ackeong>forong>s and Enell 109 110 report a drop in the feedcoefficient (amount of feed/amount of fish) ong>forong> fishraised in cages and pens in Nordic countries from2.3 to less than 1.3. Simultaneously, the nitrogencontent in the feed has fallen to 6.8% (from 7.8%)and the phosphorous content to less than 1% from1.7%. These percentages translate into decreases indischarges of phosphorous and nitrogen from netcage farming of finfish, expressed in kilograms pertonne produced, from 31 kg to less than 9.5 kg ong>forong>phosphorous and from 129 to 53 kg ong>forong> nitrogen. 11195. Shrimp farming should consider the use of naturalfeed items in the pond, such as zooplankton106 Enell, M. 1995. Environmental impact of nutrients from Nordic fish farming. Water Science and Technology 31(10):61–71. SwedishEnvironmental Research Institute (IVL), P.O. Box 21060 S-100 31 Stockholm Sweden. IWA Publishing. Abstract available athttp://www.iwaponline.com/wst/03110/wst031100061.htm107 Hall, P.O.J., Holby, O., Kollberg, S. and Samuelson, M.O. 1992 Chemical fluxes and mass balances in a marine fish cage farm. 4 Nitrogen MarineEcology Progress Series 89, 81 – 91.108 Lopez Alvarado, J. 1997. Aquafeeds and the environment. Pages 275-289 In A. Tacon and B. Basurco (eds.). Feeding tomorrow’s fish.Proceedings of the CIHEAM Network on Technology of Aquaculture in the Mediterranean, June 24-26, 1996. Cahiers, Options Mediterranees.Jointly organized by CIHEAM, IEO, and FAO. Cited inGoldburg.109 Ackeong>forong>s, H., and M. Enell. 1990. Discharge of nutrients ong>forong> Swedish fish farming to adjacent areas. AM-BIO 19(1):28-35.Cited in Ackeong>forong>s 1999.110 Ackeong>forong>s, H., and M. Enell. 1994. The release of nutrients and organic matter from aquaculture systems in Nordic countries. Journal of AppliedIchthyology 10(4):225-241. Cited in Ackeong>forong>s 1999.111 Enell, M. 1995. Environmental impact of nutrients from Nordic fish farming. Water Science and Technology 31(10):61–71. SwedishEnvironmental Research Institute (IVL), P.O. Box 21060 S-100 31 Stockholm Sweden. IWA Publishing. Abstract available athttp://www.iwaponline.com/wst/03110/wst031100061.htm29


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityand benthic organisms to supplement the ong>forong>mulateddiets. This practice will reduce the allochthonousloading into the ponds. 112 Pond managementpractices such as aeration, feeding rate and stockingrate should aim to enhance natural food in theponds.96. Formulated feed low in phosphorus and nitrogenshould be used in shrimp culture to reduce theoccurrence of eutrophication in pond water as wellas in associated water bodies. However, progress isvery slow, perhaps because of the lack of environmentalawareness among producers of shrimp feed.Improved shrimp pond management97. Shrimp farmers normally release enriched pondwaters during water exchange and flushed organicmatter from the pond bottom at the end of eachharvest to the estuary causing serious eutrophicationproblems. A decrease in the frequency of waterexchange should alleviate problems of eutrophicationin the estuary. In disease-prone or pollutedareas, culture practices show a shift towards closedculture system where water from external sources isnot required during the culture period. 11398. Use of probiotics, preferably local ones, shouldimprove the water quality of the ponds resulting ina better food conversion ratio, higher shrimp productionand cleaner effluents. 11499. Removal of sludge from shrimp pond bottomafter every harvest and extraction of nutrients fromthe sediments should not only prevent eutrophicationin the estuary, but also the recovery of nutrientsong>forong> the mass culture of algae ong>forong> shrimp hatcheries. 115In addition, pond management should ensure thatall pond effluents should be treated in a reservoircontaining macro-algae, bivalves and fish todecrease the turbidity and reduce nitrogen andphosphorus beong>forong>e being released into the sea orrecycled to the ponds. In other cases there could beefficient coupling of filter feeders and shrimp.100. Despite the many adverse environmentalimpacts arising from shrimp farming, with propertechnology and farming management, the industrycan be made ong>sustainableong>. Greater training andawareness should be given to all entrepreneurs andstakeholders, including the labourers involved inpond management.C. USE OF ENCLOSED ANDRE-CIRCULATING SYSTEMS (BOTH FORFINFISH AND SHRIMP CULTURE)101. Closed systems can contain domesticatedspecies and prevent them from mixing with wildpopulations, keeping most particulate nutrientsfrom going to the environment and also reducingto a great extent the outputs of dissolved nutrients. 116Although such water-recycling facilities are expensive,they present greater opportunities ong>forong> longrangeplanning at diminished risk ong>forong> the cultureitself and avoid excess nutrient export to naturalcoastal systems. Improvements in the design andengineering efficiencies of modern recycled-waterplants allow ong>forong> higher stocking densities, less disease,fewer breakdowns and lower operating costsas well as the reduction of eutrophication potentialto coastal waters.102. Most enclosed systems can incorporate mechanismsto reduce nutrient inputs to coastal zones.112 Shishehchian, F., F.M. Yusoff, M.S. Kamarudin and H. Omar. 1999. Nitrogenous excretion of Penaeus monodon post larvae fed with differentdiets. Marine Pollution Bulletin 39: 224-227113 Kongkeo H. 1995. How Thailand made it to the top. Infofish International 1/95 (January-February issue)114 Devaraja, T.N. F.M. Yusoff and M. Shariff. 2002. Changes in bacterial populations and shrimp production in ponds treated with commercialmicrobial products. Aquaculture. 206:245-256115 Yusoff, F.M. H.B. Matias, K. Zarina and S.M. Phang. 2001. Use of interstitial water extracted from shrimp pond bottom sediments ong>forong> marinealgal culture. Aquaculture. 201 (3-4): 263-270.116 Ackeong>forong>s, H. 1999. Environmental impacts of different farming technologies. Pages 145-169 In N. Svennevig, H. Reinertsen, and M. New (eds.).Sustainable aquaculture: food ong>forong> the future? A. A. Balkema, Rotterdam. 348 pp30


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityThe simplest systems are settling tanks ong>forong> particulateorganic matter which can be cleaned periodically.Such systems are widely used ong>forong> freshwatersalmon smolt production where biofilters, aeratedsettling tanks, are commonly used. However mostof these systems are not particularly efficient inremoving dissolved nitrogen, which may causeeutrophication. More sophisticated re-circulating systemscan recycle up to 80% of the water in the tanks.D. INTEGRATED MARICULTURE(POLYCULTURE)103. Polyculture has a long history in freshwateraquaculture (especially in China) and could beapplied more in the marine environment. Inmarine polyculture, bivalves, seaweed, and marinefinfish are produced together. By using such complementaryspecies, the waste of one can be convertedto protein by the others. In finfish production,ong>forong> example, feed that is not consumed filtersdown to suspension-feeding bivalves, or mixes withfecal waste and is taken up by primary producerssuch as seaweed (harvested directly), or by phytoplankton,which is then consumed by bivalves.104. Effluents rich in organic matter from shrimpculture can also be utilized by bivalves. Manyspecies can filter out small particles and also utilizemicroalgae from the effluent. These can be commerciallyvaluable species ong>forong> harvest or non-valuablespecies ong>forong> use as fish-meal. This ong>forong>m of cultureshows much promise in increasing sustainabilityin many types of aquaculture since it maintainsa balance of nutrients in the environment 117 andincreases the efficiency of protein production. 118 InNorthern China, ong>forong> example, kelp is cultured inthe outer portions of Sungo Bay, using nitrogenexcreted by the 2 billion scallops produced thereyearly. The potential competition of kelp with phytoplanktonthat might reduce the food supplyavailable to scallops has not, however, been investigated.119 In Chile, salmon are farmed in polyculturewith the red alga Gracilaria chilensis, whichremoves dissolved nitrogen and phosphorus andcan be sold. 120105. It should be noted that mitigation of theeffects of ong>maricultureong> nutrient input on marineecosystems requires knowledge of local and regionalcarrying capacities to receive nutrients as well asknowledge of food webs and ecosystem processes.Such studies are usually lacking from most environmentalimpact assessments and licensing ofpermits. There is also the need to articulate andcouple ong>maricultureong> with artisanal and sport fisheriesas a way of helping nutrients to cycle andproduce additional positive effects or neutralizepotential negative effects.E. PRODUCTION OF LARVAEIN AQUACULTURE FACILITIES RATHERTHAN FROM THE WILD106. In culture systems, where there are no methodsong>forong> artificial control of reproduction, or wherethey are beyond the means of local farmers, manualcollection of fry ong>forong> growout can remove significantamounts of biomass, impacting wild stocks.This should be correlated to the impact of fishingjuveniles beong>forong>e any reproductive contribution.Although under-documented, intense collection ofjuveniles can lead to disruption of natural recruitmentof local populations, thereong>forong>e affectingspecies and fisheries sustainability. Moreover, ashift in plankton biodiversity, food webs, and habi-117 See, ong>forong> example, Wilkinson, S. B., W. Z. Zheng, J. R. Allen, N. J. Fielding, V. C. Wanstall, G. Russell, and S. J. Hawkins. 1996. Water qualityimprovements in Liverpool docks: the role of filter feeders in algal and nutrient dynamics. Marine Ecology 17:197-211. Cited in Grant 1999.118 Bodvin, T., M. Indergaard, E. Norgaard, A. Jansen, and A. Skaar. 1996. Clean technology in aquaculture – a production without waste products?Hydrobiologia 327:83-86. Cited in Grant 1999.119 Grant, J. 1999. Ecological constraints on the sustainability of bivalve aquaculture. In N. Svennevig, H. Reinertsen, and M. New (eds.).Sustainable aquaculture: food ong>forong> the future? A. A. Balkema, Rotterdam. 348 pp.120 Troell, M., et al. 1997. Integrating marine cultivation of Gracilaria chilensis (Gracilariales, Rhodophyta) and salmon cages ong>forong> reducing environmental impact and increased economic output. Aquaculture 156:45-61.31


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversitytat destruction are expected. It should be emphasizedthat these impacts are highly dependant onthe species reproductive strategy and ecosystemsensitivity. Harvesting wild seeds, followed bytransfers might also lead to a loss of biodiversitythrough effects on genetic resources heterogeneityof native stocks. Although it may impact socialactivities, an efficient mitigation process is to producelarvae in aquaculture facilities so as to sustainaquaculture production. Implementation of such aplan can lead to recovery of affected biodiversity.However, hatchery production can also affect biodiversityif not properly managed.107. New technologies such as cryo-preservationcould be considered as a mitigation process to limitpressure on wild populations and optimize broodstock management and seed supply at the hatcherylevel. Additionally, there is a critical need ong>forong> geneticdatabases to assess wild genetic resources andong>forong>ecast impacts from cultured species.F. MITIGATING THE EFFECTSOF ANTIBIOTICS108. The overuse of antibiotics has caused widespreadconcern about the emergence and selectionof resistant bacteria. It is generally accepted thatantibiotic resistance is associated with the frequencyof use in the environment. 121109. Training should be provided in the use, andthe harmful effects of, antibiotics to ensure theirproper administration. In many cases, the outbreakof disease is due to poor health management practicesresulting in stress, and thus making the culturedanimals more susceptible to diseases. Proactivemonitoring and use of proper diagnostic tools areoften best practices to avoid a disease outbreak.110. Regulations to reduce the use of antibioticsmust be drawn up and enong>forong>ced. More attentionshould be paid to the reduction of stress factors byimproving health management practices. There hasbeen a general move in some countries in theindustry away from heavy use of man-made chemicalsand toward lower stocking densities and theuse of probiotics (to improve water quality).111. This situation, combined with public resistanceto antibiotic use in some countries, has led tointensive research on vaccines ong>forong> infectious diseasesof farmed marine animals. Vaccination cantreat some infectious diseases highly effectively, 122ong>forong> example coldwater vibriosis, once a seriousproblem ong>forong> salmon farms in Norway. 123 Sandnesand Ervik 124 indicated a dramatic reduction in theuse of antibiotics after the discovery of the vaccineagainst furunculosis. The use of antibiotics wasreduced from 585 gr./ton of produced salmon in1987 to 8 gr./ton in 1995.112. Vaccines can be administered orally or byinjection or through immersion or spraying. 125Major diseases ong>forong> which vaccines have been developedinclude furunculosis, coldwater vibriosis, vibriosis,yersiniosis, and edwardsiellosis. 126 In Norway,121 Hamilton-Miller JMI. 1990. The emergence of antibiotic resistance: myths and facts in clinical practice. Interns. Cares Med. 16 (Suppl. 13): 206-211, and others.122 Hastein, T. 1995. Disease problems, use of drugs, resistance problems and preventive measures in fish farming worldwide. Pages 183-194 In H.Reinertsen, and H. Haaland (eds.). Sustainable fish farming, Proceedings of the First International Symposium on Sustainable Fish Farming,August 28-31, 1994. Oslo, Norway. Rotterdam: A. A. Balkema. Cited in Goldburg.123 Norwegian Fish Farmers’ Association. 1990. The Norwegian fish farming industry in harmony with the environment. Trondheim/ Tromso,Norway: Norwegian Fish Farmers’ Association. Cited in OTA (1995). (Cited in Goldburg.)124 Sandnes, K., and A. Ervik. 1999. Industrial marine fish farming. Pages 97-107 In N. Svennevig, H. Reinertsen, and M. New (eds.). Sustainableaquaculture: food ong>forong> the future? A. A. Balkema, Rotterdam. 348 pp125 Avault, J. W. 1997. Prevention of diseases: some fundamentals reviewed. Aquaculture Magazine (March/April. 1997):78-83. Cited in Goldburg.126 Hastein, T. 1995. Disease problems, use of drugs, resistance problems and preventive measures in fish farming worldwide. Pages 183-194 In H.Reinertsen, and H. Haaland (eds.). Sustainable fish farming, Proceedings of the First International Symposium on Sustainable Fish Farming,August 28-31, 1994. Oslo, Norway. Rotterdam: A. A. Balkema. Cited in Goldburg.32


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityong>maricultureong> of salmon increased after the reductionin the use of antibiotics in 2000.113. Further research should be encouraged in thisarea, and should include the close involvement offarming companies. Often there will be the need ong>forong>economic assistance with such technological development,especially ong>forong> developing countries.G. MITIGATING THE EFFECTSOF PESTICIDES,PISCICIDES AND PARASITICIDES114. Pesticides and piscicides are used to removepest species from the surrounding environment.Residues are often highly toxic and may persist ong>forong>weeks in the water and sediment often killing nontargetorganisms. Lower stocking densities, largeenough distances between farms, prophylacticmethods and general management procedures(which includes proper training) should greatlyhelp prevent the use of chemicals to control externalparasites. Alternatively, totally self-containedsystems should be used. Further detail on the use ofchemicals and antiobiotics, as well as on mitigationmeasures, can be found in GESAMP report No. 65. 127H. REDUCING THE USE OF HORMONES115. Alternatives ong>forong> the use of hormones include(a) Proper genetic-selection programmes, whichcould provide better offspring and enhancecertain traits otherwise achieved by usinghormones;(b) Use of photoperiod management in industrialproduction of salmon. This is probably oneof the most promising mitigation tools ong>forong>the use of hormones in the field of salmonproduction. Similar techniques could bedeveloped ong>forong> other species;(c)Cryo-preservation could be considered as amitigation process to optimize broodstockmanagement and seed supply at the hatcherylevel.I. PREVENTING DISEASE TRANSMISSION116. Prevention should be encouraged as a mitigationprocess ong>forong> disease transmission since no curesexist ong>forong> several diseases in cultured species.Improved monitoring programmes ong>forong> known andemerging diseases should be encouraged, as well asthe use of biomolecular tools ong>forong> diagnostics.117. Mitigation should include contingency measurementssuch as quarantine stations and completeself-containment of infected organisms to be treatedor to be transported ong>forong> elimination. Effluent ofcontained systems should be treated with ultravioletor ozone.118. To avoid diseases, protocols ong>forong> quarantine andmovement of animals should be in place to minimizetransmission of diseases. International codesof practice, agreements and technical guidelinesused to minimize the risk of diseases associatedwith movement of aquatic animals should beadopted. Examples of such are the OIEInternational Aquatic Animal Health Code andDiagnostic Manual ong>forong> Aquatic Animals Diseasesand Code of Practice on the Introductions andTransfers of Marine Organisms of the InternationalCouncil ong>forong> Exploration of the Seas (ICES). In addition,there is a need ong>forong> regionally-orientated guidelinessuch as the most recent (2000) FAO/Networkof Aquaculture Centres in Asia-Pacific (NACA) AsiaRegional Technical Guidelines on HealthManagement ong>forong> the Responsible Movement of LiveAquatic Animals and the Beijing Consensus andImplementation Strategy. Collaboration betweenregional and International agencies such as NACA,127 GESAMP (IMO/FAO/UNESCO-IOC/WMO/WHO/IAEA/UN/UNEP Joint Group of Experts on the Scientific Aspects of MarineEnvironmental Protection). 1997. Towards safe and effective use of chemicals in coastal aquaculture. Reports and Studies, GESAMP. No. 65.Rome, FAO. 1997. 40 p.33


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityOIE, ICES and FAO should be further strengthened,and should include close collaboration on theissues related to transboundary movement ofaquatic animals.119. The use of indigenous species ong>forong> cultureshould be encouraged. In addition, strengtheningof aquatic animal health capacity, along withimproved laboratory facilities, control protocolsand therapeutic strategies should be put in place tominimize losses due to disease transmission.120. In addition to the above, the establishmentand implementation of a harmonized regional certificationsystem, establishment of regional referencelaboratories ong>forong> standardization and validationof diagnosis, and establishment of regionaltraining programmes in aquatic animal healthissues including trans-boundary movement, riskassessment and contingency plans, are vital ong>forong> preventingdisease transmission.J. PREVENTING ESCAPESExotic species121. Although geographic constraints may be difficultto address, especially in developing countries,ong>maricultureong> of endemic species should be encouraged.Appropriate safeguards to conserve geneticdiversity should accompany ong>maricultureong> operations.Risk analysis and/or environmental riskassessment can be carried out beong>forong>e any introductionso as to assess likely impacts, and quarantineprocedures followed. 128 Improved managementpractices can limit the spread of escapes, includingsite selection outside their reproductive range toavoid reproduction. Use of sterile individuals canalso be recommended when the risk to interactwith native population is limited. Other contingencymeasurements should be mandatory in caseof accidental escapes. As an example, a large-scaleescape took place in Chile during 1995-96, andlocal fishermen took care of a large proportion ofthe escaped salmon, 129 demonstrating that recoveryof escapees is possible.Native species122. Farmed native species may cause a decrease inintra-specific genetic variability when released tothe environment. Similarly, transferring seed withinthe geographical range of the species may affectgenetic variability. Thereong>forong>e, a proper broodstockmanagementplan is critical. An alternative mitigationapproach is to limit the spread of the selectedstrains by supporting the production of sterileindividuals.128 ICES. 1995. ICES Code of Practice on the Introductins and Transfers of Marine Organisms 1994.129 Soto, D., F. Jara and C. Moreno. 2001. Escaped salmon in the Chiloe and Aysen inner seas, southern Chile: facing ecological and social conflicts. Ecological Applications Vol. 11, No. 6, pp. 1750-1762.34


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversity4. ENHANCING THE POSITIVE EFFECTS OF MARICULTUREON MARINE AND COASTAL BIOLOGICAL DIVERSITY AND PRODUCTIVITY123. Mariculture could help preserve biodiversitywhen, as a successful economic activity, it can providelocal relief to the pressure on commonly harvestedaquatic species. However, globally and indirectly,aquaculture has been blamed ong>forong> over-harvestingof aquatic resources to obtain fishmeal, 130although ong>maricultureong> is a more efficient fishmealuser than other ong>forong>ms of food production. 131124. Nutrient loads from ong>maricultureong> can generateeutrophication and also cause biodiversity losses.However nutrient loads in oligotrophic tomesotrophic coastal zones could enhance productivityand increase biodiversity, although these arechanges from natural conditions. One way todiminish the ecological footprint of salmon farmingis to prevent nutrients from being lost to bacterialdegradation 132 . This can be achieved by findingalternative pathways (to direct bacterial degradation)that will utilize native species and ecosystemprocesses. Coupling these processes to the ong>maricultureong>activity is still a challenge. Some ecologicalhypotheses have proposed that increased nutrientinputs could provide extended food webs 133 andpossibly increased biodiversity, at least within acertain range.125. Best-site selection (including optimal flushingand dispersal of nutrients) could actually promotean increase of local and total productivity, especiallyin oligotrophic and mesotrophic systems, particularlywhen additional substrate heterogeneity,such as building of artificial reefs to soft bottomareas, is provided. 134 Angel et al 135 showed a relevantimprovement of environmental conditionsaround fin fish farms by using artificial reefs. Otherpossibilities include coupling with some ong>forong>ms ofshellfish culture or natural shellfish beds. All thesepossibilities should be explored.126. Additionally, some ong>forong>ms of ong>maricultureong>, suchas shellfish and macro-algae production, couldcontribute to biodiversity enhancement by providinghabitat structure and food. Such effect couldenhance food web structure, fluxes, and interactionbetween ong>maricultureong> and wild fish and invertebrates.127. Although not directly connected to ong>maricultureong>,overfishing and other activities affect biodiversityand produce depletion of wild stocks.Mariculture, under controlled reproductive activity,could be considered as a mitigation process ong>forong>biodiversity recovery from the effects of fishing.However, this should be addressed through a geneticallysound broodstock management plan in orderto avoid reducing genetic variability.130 Soto, D. and F. Jara. 1999. Relevance of Ecosystemic services provided by species assemblages: coupling salmon farming with biodiversity useand management. 1999. In: Schei, Sandlund and Stran (Eds), Norway/UN Conference on the ecosystem approach ong>forong> ong>sustainableong> use ofbiodiversity pp 133-137.131 Tidwell, J.H. and G. L. Allan. 2001. Fish as food: aquaculture's contribution. Ecological and economic impacts and contributions of fishfarming and capture fisheries EMBO reports 2: 958-963132 Folke, C, N. Kautsky & M. Troell (1997). Salmon farming in contex: response to Black et al. Journal of Experimental Management 50: 95-103133 Person, L. 1994. Natural patterns of shifts in fish communities – mechanisms and constrains on perturbation sustenance. In: G. Cowx (Ed)“Rehabilitation of freshwater fisheries”, pp 421-434. Fishig News Books, Blackwell, U.K.134 Jara, F. and R. Cespedes. 1994. An experimental evaluation of habitat enhancement on homogeneous marine bottoms in southern Chile.Bulletin of Marine Science 55:295-307.135 Angel, D. N. Eden, S. Breitstein, A. Yurman, T. Katz and E. Spanier. 2002. In situ biofiltration: a means to limit the dispersal of effluents frommarine finfish aquaculture. Hydrobiologia 469: 1-10.35


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversity5. MARICULTURE GUIDELINES RELATED TO BIODIVERSITYA. PRINCIPLES AND STANDARDS128. Although no set of internationally agreed criteriahas yet been developed specifically ong>forong> theenvironmental regulation of aquaculture operations,many national and regional regulations andlaws, largely based on scientifically accepted environmentalcriteria, have been adopted. However,the ICES recently prepared draft guidelines ong>forong> thepreparation of environmental impact assessmentdocuments related to shellfish ong>maricultureong> 136 andthe European Union funded the MARAQUA project,which also presented scientific principles underlyingthe monitoring of the environmental impactsof aquaculture. A variety of principles and standardsare voluntarily being applied to the industryin an attempt to decrease its environmental impactand improve its public image. In addition, in itsdecision VI/7 A, the Conference of the Parties tothe ong>Conventionong> on Biological Diversity adoptedguidelines ong>forong> incorporating biodiversity-relatedissues into environmental impact assessments.129. Article 9 of the FAO Code of Conduct ong>forong>Responsible Fisheries provides a set of voluntaryprinciples and standards that, if applied, ensurethat potential social and environmental problemsassociated with aquaculture development are dulyaddressed and that aquaculture develops in a ong>sustainableong>manner. However, providing an enablingenvironment ong>forong> ong>sustainableong> development in ong>maricultureong>is not only the responsibility of governmentsand aquaculture producers, but also theresponsibility of scientists, media, financial institutionsand special interest groups. Additional principlesand standards include the ICES Code ofConduct, and NACA Code.B. CERTIFICATION130. Aquaculture operations can be certified as: (i)producing cultured species to guidelines or codesof practice, (ii) producing cultured species to reputableand recognized standards, or (iii) throughoperational audits and assessments as producingspecies to defined criteria. The following sectiondiscusses these three methods of certification:(a) Aquaculture operations are officially certifiedas producing cultured species according toguidelines or codes of practice, sometimesfollowed by Eco-labeling of the product. Forexample, the Global Aquaculture Alliance(GAA) is an international, non-profit tradeassociation, which promotes environmentallyresponsible aquaculture through an ecolabelingprogramme called the “ResponsibleAquaculture Program”, which includes codesof conduct ong>forong> responsible aquaculture andcertification production standards. There areother schemes putting more emphasis onthird-party certification. As an example, theGAA Codes of Practice ong>forong> ResponsibleShrimp Farming include sections on mangroves;site evaluation; design and construction;feeds and feed use, shrimp health management;therapeutic agents and other chemicals;general pond operations; effluents andsolid wastes; and community and employeerelations;(b) Aquaculture operations may be certified asproducing cultured species to reputable andrecognized organic standards. For example,the International Federation of OrganicAgriculture Movements Basic Standards(IFOAM) provide organic production standardsong>forong> agriculture and aquaculture that areused by certifying bodies and standard-settingorganizations worldwide as a frameworkong>forong> development of certification criteria.136 See http://www.ices.dk/reports/MCC/2002/WGEIM02.pdf.36


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversity(c)IFOAM includes criteria ong>forong> rearing of fishand servicing of cages; water quality; feeding;health; fish re-stocking, breeding and origin;propagation of fish stocks and breeding; andtransport, killing and processing. Someorganizations that are using IFOAM standardsare The Naturland Standards ong>forong> theProduction of Salmon and Other Cold WaterFish (primarily in use in Germany andIreland ong>forong> trout and salmon farming), KRAVKontroll AB Organic Standards 1999 (certifiessalmon, trout, Arctic char and Browntrout farming in Sweden), NationalAssociation ong>forong> Sustainable AgricultureAustralia (used in Australia, PNG, Sri Lankaand Indonesia), BioGro New ZealandProduction Standards and AgroEco (based inHolland, organic shrimp farming inEcuador);Aquaculture operations may be certified,through operational audits and assessments,as producing cultured species to defined criteria.Certification is followed by ecolabellingof the product and often requiresthe implementation of a documentedEnvironmental Management System (EMS).The International Organization ong>forong>Standardization (ISO) has developed sets ofgeneric management system standards, whichprovide general standards and criteria ong>forong> thedevelopment of an EMS. The ISO 14001Environmental Management System has beenused by various organizations as a basis ong>forong>environmental certification. One such organizationis the European Eco-Managementand Audit Scheme (EMAS). 137 EMAS is amanagement tool ong>forong> companies and otherorganizations to evaluate, report and improvetheir environmental perong>forong>mance. Participationis voluntary and extends to public or privateorganizations operating in the European Unionand the European Economic Area. An increasingnumber of candidate countries are alsoimplementing the scheme in preparation ong>forong>their accession to the EU. Some companies,local authorities and other organizations outsidethe European Economic Area are alreadyputting EMAS into practice inong>forong>mally andbenefiting from continuous improved environmentalperong>forong>mance.131. Appropriate monitoring programmes areessential ong>forong> achieving and maintaining an environmentallyfriendly ong>maricultureong> industry. GESAMP 138has produced a working definition ong>forong> monitoringin relation to aquaculture as “the regular collection,normally under regulatory mandate, of biological,chemical or physical data from predefined locationssuch that ecological changes attributable toaquaculture wastes can be quantified and evaluated”.GESAMP also emphasise that in order to haveefficient regulatory tools, monitoring programmesmust be integrated with simulation models that canbe predict the impact of a given operation andrespond with remedial action if the threshold levelsong>forong> environmentally acceptable impact arebreached. However, there is no definition of whatsuch environmentally acceptable impact means,and what indeed are safe limits ong>forong> impacts.132. Monitoring and regulating the productionprocess and the extent of the operation is also aprerequisite to integrating ong>maricultureong> into coastalzone planning. It is only when adequate data areavailable that environmental, including biodiversity,and ong>maricultureong> needs can be securely ong>forong>mulated.It thereong>forong>e follows that integration will be successfulwhen all participants (users of the coastalresource) are able to identify their environmentalneeds and impacts while demonstrating a highlevel of credibility in their assessments. To increasepublic confidence, it is recommended that the137 European Eco-Management and Audit Scheme. http://europa.eu.int/comm/environment/emas/index_en.htm138 GESAMP (IMO/FAO/UNESCO-IOC/WMO/WHO/IAEA/UN/UNEP Joint Group of Experts on the Scientific Aspects of MarineEnvironmental Protection). 1996. Monitoring of Ecological Effects of Coastal Aquaculture Wastes. Reports and Studies, GESAMP. No. 57. Rome, FAO.45 p.37


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityresults of ongoing monitoring programmes areaccessible to the public.133. Setting threshold levels ong>forong> environmentalimpacts or environmental quality standards (EQS)requires a close cooperation between authoritieswho can determine what impact is acceptable, andscientists who understand what this means inmeasurable parameters. In many countries, the taskis determined by environmental quality objectives(EQO) from which EQS values are derived. AnEQO/EQS system is appropriate since it will contributeto transparent regulatory systems that arebased on political decisions and public acceptance.This approach opens the possibility of definingzones with different allowable impacts and accordingly,different EQS values. 139134. Monitoring programmes must concentrate onthe main impacts of ong>maricultureong>. It has been suggestedthat the following criteria should be used to select theimpacts on which to place the main emphasis:(a) The sum of the impacts must have relevanceong>forong> both the environment and the ong>maricultureong>operation;(b) The impact must be convenient ong>forong> monitoring,ong>forong> example, routine analytical methodsmust be available and the signals must be distinguishableong>forong> background levels;(c) Scientific inong>forong>mation must be available to setadequate EQS;(d) The monitoring must be cost efficient, as manyong>maricultureong> operations are small enterprises.C. AQUACULTURE LAWSAND REGULATIONS135. Due to growing global concerns over the environmentalimpact of aquaculture and its effects onbiodiversity, many countries have enacted laws thatspecifically regulate the aquaculture industry.Unong>forong>tunately, many countries still depend onmore general environmental protection laws orlocal environmental plans that are sometimes hardto enong>forong>ce in relation to aquaculture operations orare vulnerable to political or legal manipulation.Many countries require environmental impactassessments (EIAs) to be carried out ong>forong> proposedaquaculture projects, leaving established operationsunregulated.136. Some examples of aquaculture-related lawsand regulations include:(a) To date most EU Member States have determinedthat only finfish aquaculture projectsshould be subject to EIA and few shellfishprojects, regardless of scale, have been subjectto EIA. The MARAQUA project recommended,however, the adoption of the EIA processong>forong> all aquaculture operations;(b) There are significant cost implications in carryingout a full EIA ong>forong> new developments,particularly ong>forong> smaller operators that dominatethe industry in many countries. Such asituation may be resolved somewhat byimplementing a “scaled down” version of anEIA ong>forong> proposed developments. As an alternativeto a full EIA Fernandes et al 140 recommendedthat in some instances environmentalstudies of a more limited nature could becarried out and the results provided to theregulatory authorities in the ong>forong>m of an“Environmental Report” when making anapplication ong>forong> a fishfarming permit.(c) ICES (2002) concluded that there is a needong>forong> the refinement of criteria to determine ifan EIS is required ong>forong> shellfish operation andrecommended that further work should becarried out to determine appropriate thresholdcriteria to determine which type of shellfishprojects should be subject to: i) an EIA,ii) and environmental report or iii) no environmentalassessment;139 Henderson A.R. and I.M. Davies. 2000. Review of aquaculture, its regulation and monitoring in Scotland. Journal of Applied Ichthyology, July2000, vol. 16, no. 4-5, pp. 200-208140 Fernandes, T.F., K.L. Miller et P.A. Read. 2000. Monitoring and regulation of marine aquaculture in Europe. J. Appl. Ichthyol. 16: 138-143.38


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversity(d)(e)(f)(g)(h) Sri Lanka’s National Environmental ActIn Malaysia, an EIA is required ong>forong> “land19.300); 144 (92/43/EEC) are important in this regard.based aquaculture projects accompanied byclearing of mangrove swamp ong>forong>ests coveringan area of 50 hectares or more,” pursuantto the Environmental Quality (PrescribedActivities) (Environmental Impact Assessment)Order 1987 of the Environmental Quality Act1974. However, the EIA law in relation to(NEA) requires an EIA ong>forong> any fisheries projectlarger than 4 hectares and prohibits anyperson from discharging, depositing or emittingwaste into the environment that willcause pollution without a license issued bythe authority or in accordance with standardsprescribed under the act. This involves theaquaculture projects is weak. There is a voluntaryissuing of license by the Central“Code of Practice ong>forong> Aquaculture” (6thSept 1999); 141Environmental Authority (CEA). In addition,the Fisheries & Aquaculture Resources ActNew South Wales (Australia) regulates aquacultureNo. 2 of 1996, includes rules ong>forong> the manage-pursuant to Part 6 of the Fisheriesment, regulation, conservation and develop-Management Act, the Fisheries Managementment of fisheries and aquatic resources in SriAquaculture Regulations 1995 and by theLanka. 145Environmental Planning and Assessment Act.These laws designate aquaculture as a “designated137. In recent years, the increasing global concerndevelopment,” which requires an EIA; 142 ong>forong> the destruction of mangrove habitat by aqua-In 1996 the Supreme Court of India ordered culture operations, most commonly shrimp farmingthe closure and rehabilitation of several nontraditionalin brackish-water ponds, has led to more strin-large-scale aquaculture industries gent regulations. In 2000, only Belize and Ecuadorthat have caused harm to India’s coastal areas. had laws in place that specifically prohibit theTraditional approaches and improved traditionaldestruction of mangroves resulting from aquacul-methods of aquaculture were allowed ture projects, while other countries, such as Costato continue. The Supreme Court based its Rica, Malaysia, India, Thailand and China, dependorder on the reasoning that aquaculture is an on EIAs or moratoriums on development projectsindustry and is hence prohibited under the in mangroves, and general environmental regulations.Coastal Regulation Zone (CRZ) notification(which prohibits new industries or expansionwithin the CRZ area); 143138. Other legislation is in place that should beIn Chile, an EIA could be required ong>forong> any considered when assessing proposals ong>forong> ong>maricultureong>project proposed in coastal areas pursuant toprojects. In the European Union, the Birdsthe Environmental Framework Law (No. Directive (79/409/EEC) and the Habitats Directive141 The Environmental Law Alliance Worldwide (E-LAW). 2000. Survey of laws on aquaculture. Available on the Industrial Shrimp Action Networkwebsite at http://www.shrimpaction.com/ESurvey.html142 Ibid.143 Bonora, M. 1999. Shrimp Aquaculture in India. The Shrimp Sentinel Online, National Reports.http://www.earthsummitwatch.org/shrimp/index.html144 The Environmental Law Alliance Worldwide (E-LAW). 2000. Survey of laws on aquaculture. Available on the Industrial Shrimp Action Networkwebsite at http://www.shrimpaction.com/ESurvey.html145 The Environmental Law Alliance Worldwide (E-LAW). 2000. Survey of laws on aquaculture. Available on the Industrial Shrimp Action Networkwebsite at http://www.shrimpaction.com/ESurvey.html39


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityD. SPECIFIC CRITERIA ON THE EFFECTSOF MARICULTURE ON BIODIVERSITY139. Although the Group was unable to discoverany established sets or reviews of ong>maricultureong> criteria,some examples of specific criteria that havebeen adopted as indicators of environmentallysound or ong>sustainableong> aquaculture can be cited.140. For example, the Government of Japan hasenacted regulations to ensure ong>sustainableong> aquaculture,with regard to improvement and preservationof aquaculture grounds and the spread of disease.In the case of surface aquaculture, it was determinedthat oxygen levels in cages should be morethan 4.0 ml/L of sea water, the quantity of sulfide inthe mud under cages should be less than the oxygenavailable to reset the sulfide, and benthos, such aslugworms, should be present in the mud under thecages. 146141. Norway has established quality criteria ong>forong>fish oil used in fish feed by commercial fish farmers.The feed must contain 5% free fatty acids, have atotal oxidation value of 30 and contain only 0.5%water and impurities. 147 This is significant becauseincreasing the fat content in feeds helps reducewastage by supplying a ready energy source andreducing the nitrogenous waste producing breakdownof protein ong>forong> energy.146 The International Organization ong>forong> Standardization. http://www.iso.ch/iso/en/ISOOnline.frontpage147 Albrektsen, S., Ø. Høstmark, and K. Hamre. 2001. Fish silage - effects on fish oil quality and on growth perong>forong>mance and quality of Atlanticsalmon (Salmo salar L.). Cultivation of Salmon II Conference, 7-10 May, 2001. Bergen, Norway, Abstract available as pdf file at:http://www5.imr.no:8080/salmon/innhold.htm40


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityANNEX ICOMPOSITION OF THE AD HOC TECHNICAL EXPERT GROUPON MARICULTURETechnical experts:Mr. A.K. Armah, GhanaMs. Daisy C. Arroyo Mora, Costa RicaMr. Stefano Cataudella, ItalyMr. S.U.K Ekaratne, Sri LankaMs. Vlasta Franicevic, ´ CroatiaMr. Phillippe Goulletquer, FranceMr. Manal Nader, LebanonMr. Fabian Pina Amargos, CubaMs. Shyama Rathacharen, MauritiusMr. Arturas Razinkovas, LithuaniaMr. Tetsuo Seki, JapanMr. Mohamed Shariff, MalaysiaMs. Doris Soto, ChileMr. Uwe Waller, GermanyMs. Stella Williams, NigeriaMr. Serguei Zagranitchnyi, Russia^Observers:Mr. Devin Bartley, FAOMr. Uwe Barg, FAOMr. Alessandro Lovatelli, FAOMr. Terry McMahon, OSPAR CommissionMs. Fatimah Md.Yusoff, Universiti Putra MalaysiaCBD Secretariat:Ms. Marjo Vierros41


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityANNEX IIDESCRIPTION OF IMPACTS, EFFECTS, MITIGATION TOOLS AND RESULTSProblemImpactMain mitigation tool,enhancement ofbeneficial effectAssociatedmitigation toolResults of mitigation1) Excess nutrientaddition by fin fish andshrimp ong>maricultureong>(or other carnivorousorganisms) to the watercolumn and sedimentsPotential eutrophicationwith biodiversity lossesa) Best site selection(including optimalflushing and dispersal ofnutrientsa.1. Offer of alternativefisheries resources.a.1.Decrease of local nutrientinputs, lesser effectseven positive effects onlocal biodiversity andecosystem processes byreleasing harvesting pressureover wild stocks atlocal scalea.2.Integrated aquaculture.Culturing different speciestogether (eg. Salmon w/mussels, or salmon w/macroalgae)Increased habitat structure,more efficient use of nutrients,increased nutrientfluxes, lesser effects or positiveeffects on biodiversitya.3. Coupling w/artificialreefs, sport fishing, localfisheriesIncreased habitat structure,more efficient use of nutrients,increased nutrientfluxes, lesser effects or positiveeffects on biodiversityb) Better maanagement,decrease conversion ratios(improved specializedtraining and education)b.1-fin-fishb.2. shrimpDecreased nutrient inputsto environment, lessereffects or even positiveeffects on biodiversity andecosystem processesc) Changes in nutrition,low P, N dietsDecreased nutrient inputsto environment, lessereffects on biodiversity andecosystem processesd) Reducing stockingdensitye) Use of enclosed, orre-circulating systems(both ong>forong> finfish andshrimp culture)Decreased nutrient inputsto environment, lessereffects on biodiversity andecosystem processes2) nutrients in outflowfrom enclosed systems,tank or pond ong>maricultureong>(finfish/shrimp)mpactRemoval of sludge fromfish/shrimp pond watersand treatment of effluents,use of biofilters and externalsettling tanksDecreased nutrient inputsto environment, lessereffects on biodiversity andecosystem processes42


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityProblemImpactMain mitigation tool,enhancement ofbeneficial effectAssociatedmitigation toolResults of mitigationIntegrated shrimp pondculture in self containedre _circulating systems.Coupling with seaweed,and fish production(policultures)Decrease of nutrientdischarges, lesser effectson local biodiversity andecosystem processesAlternating shrimp andfish cultureDecrease of nutrientdischarges, lesser effectson local biodiversity andecosystem processes3) Excess sediment accumulationby shellfishong>maricultureong>Potential eutrophicationwith biodiversity losses onthe bottomBest site selection (accordingto carrying capacityto receive and processorganic mater on sediments,eg. Local currents)Decrease of local organicmatter inputs to sediments,lesser effects on benthicbiodiversity and ecosystemprocessesAdditionally there are positiveeffect on water quality4) Decreased planktonicbiomass by shellfishoverstockingShifting in planktonicpopulations, productivityand food websBest site selectionReducing rearing density(improving training andeducation)Recovering biodiversity andoriginal food webs andprocesses5) Habitat destruction byshrimp farming in coastalareas and mangrovesDecrease in habitat heterogeneity(nursery grounds)and biodiversity in generala) Site selection outsidemangrove zoneb) Mangrove recovery andrestorationMaintaining biodiversityRecovering biodiversity6) Mangrove disruptionong>forong> oyster seed and adultcollectionDecrease in habitat heterogeneity(nursery grounds)and biodiversity in generalAquaculture of oystersRecovering mangrove andassociated biodiversity7) Use of wild seeds(shrimp, some bivalves,some fish)Depletion of larvae in thewild, depletion of planktonbiodiversity, habitatdestruction.Producing larvae in aquaculturefacilities (reproductioncontrol)Recovering, maintainingbiodiversity8) Use of antibiotics inopen systemsIncreased bacterial resistance,with decreased naturalbacterial biodiversity(losing some naturalprocesses), decrease biodiversitydue to increasedisease exposurea) Prevention of diseases =Improved health managementpractices (Trainingand education improvement)Recovery maintenanceof biodiversity and ecosystemicprocesses43


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityProblemImpactMain mitigation tool,enhancement ofbeneficial effectAssociatedmitigation toolResults of mitigationb) Pro active monitoringand use of properdiagnostic toolsAvoidance of biodiversitydamagec) Improved administrationmethods ong>forong> medication,eg. totally enclosedsystem ong>forong> treatmentAvoidance of biodiversitydamaged) Introduction of probiotics(neutral effects onbiodiversity?)e) Development ofvaccines (research andtraining)Avoidance of biodiversitydamage9) Use of pesticides, piscicides,fungicides, otherchemicals in open systemsDecrease of biodiversitya) Better managementpractices (training andeducation)Avoidance or diminishingbiodiversity damageb) Totally self containedsystems ong>forong> treatmentAvoiding damage tobiodiversity10) Use of antifoulingpaints in fin-fish pensImposex on molluscs, andother unong>forong>eseen effectson biodiversitya) Better managementpractices (training andeducation)Avoidance or diminishingbiodiversity damageb) Best site selection, highflushing ratesAvoiding damage tobiodiversityc) Increase frequency ofnet changesAvoiding damage tobiodiversityd) Alternative paints/netting/ or other safeantifouling approachAvoiding damage tobiodiversity11) Use of hormones(growth etc.)Unong>forong>eseen effects onbiodiversityBetter genetic selection,improvement of managementpracticesAvoiding damage tobiodiversity12) Disease transmissionLosses of biodiversity dueto diseasesa) Better managementpractices (training andeducation)Avoiding damage tobiodiversityb) Pro active monitoringand use of properdiagnostic toolsAvoiding damage tobiodiversityc) Enclosed systems orrecirculating systemsUV or other treatmentof outflowAvoiding damage tobiodiversity44


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityProblemImpactMain mitigation tool,enhancement ofbeneficial effectAssociatedmitigation toolResults of mitigation13) Escapes(exotic species)Biodiversity losses throughcompetition, predation,habitat destruction,disease transmissiona) Better managementpractices (training andeducation)Avoiding or diminishingdamage to biodiversityb) Discouraging exoticspecies ong>maricultureong>Encouraging nativespecies ong>maricultureong>Avoiding or diminishingdamage to biodiversityc) Risk assessmentprevious introductionAvoiding or diminishingdamage to biodiversityd) Encouraging collectionof escapees by fishermanor others (eradicationprograms)Avoiding or diminishingdamage to biodiversitye) Encourage sterilityAvoiding or diminishingdamage to biodiversityf) Site selection outsideenvironmental conditionsong>forong> reproductive successAvoiding or diminishingdamage to biodiversity14) Escapes (local species)Decrease geneticbiodiversitya) Proper genetic broodstock managementAvoiding or diminishinggenetic variability andother biodiversity lossesb) Encourage sterility (?)15) GMO ong>maricultureong>Biodiversity losses throughcompetition, predation,habitat destruction,disease transmissionPrevious comprehensivescientific evaluationContained orre-circulating systemAvoiding or diminishinggenetic and biodiversitylosses16) Over fishing anddepletion of wild stocks.Biodiversity lossesa) Mariculture ong>forong> searanchingRecovery of biodiversity(but be careful withgenetic variabilityreduction)b) Shellfish ong>maricultureong>providing habitatstructure and foodPositive enhancement oflocal biodiversity, byenhancing food web fluxesand interaction betweenong>maricultureong> and wild fishand invertebratesc) Algae culture couldprovide more refuge andhabitat structureIncreased biodiversity45


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityANNEX IIIRECOMMENDATIONS OF THE AD HOC TECHNICAL EXPERT GROUPON MARICULTUREThe Expert Group thanks FAO ong>forong> its technicalsupport and ong>forong> the provision of meeting facilitiesand welcomes the efong>forong>ts of the FAO in implementingthe Code of Conduct on Responsible Fisheries.1. General recommendationsThe Expert Group:(a) Recommends that ong>Conventionong> on BiologicalDiversity should adopt the Article 9 of the‘Aquaculture Development’ of CCRF (FAO,1995) and other provisions of the CCRF ong>forong>dealing with ong>maricultureong> because it has thenecessary ingredients to develop legislationand policy framework at national, regionaland international levels;(b) Notes that the FAO glossary of terms isskewed towards marine capture fisheries, andrecommends that this glossary be expandedin regards to its terminology related to aquaculture;(c) Recommends that the ong>Conventionong> onBiological Diversity, FAO and other relevantorganizations harmonize the use of terms inregards to ong>maricultureong> by further developingand adopting the FAO glossary;(d) Recommends that the ong>Conventionong> onBiological Diversity collaborate with the FAO,and other relevant organizations to developprogrammes to assess the consequences ofong>maricultureong> ong>forong> biodiversity;(e) Recommends the promotion of technicalexchange and training programmes, andtransfer of tools and technology;(f) Recommends the facilitation of the provisionof funding ong>forong> country-level, regional,and international activities relating to the priorityneeds identified by the Expert Group;(g) Recommends that the ong>Conventionong> onBiological Diversity undertake a comprehensivereview of all relevant documents on goodpractices in management relevant to ong>maricultureong>;(h) Recommends that the ong>Conventionong> onBiological Diversity in collaboration with relevantbodies review and evaluate meanswhere ong>maricultureong> can be used to help restoreor maintain biodiversity;(i) Recommends promotion of good managementand good legal and institutionalarrangements ong>forong> ong>sustainableong> ong>maricultureong>.2. Mitigating adverse effects of ong>maricultureong> onmarine and coastal biodiversityThe Expert Group recognizes the complexity ofong>maricultureong> activities, the highly variable circumstancesof different geographical areas, ong>maricultureong>practices and cultured species, social, cultural andeconomic conditions. Although this diversity willinfluence mitigation options, the Group recommendsthe use of following methods and techniquesong>forong> the mitigation of adverse biodiversityrelatedeffects of ong>maricultureong>:(a) Environmental impact assessments (EIAs) orsimilar assessment and monitoring proceduresshould be made mandatory ong>forong> ong>maricultureong>developments with due considerationof scale and nature of the operation, as well asthe carrying capacities of the ecosystem onthe ecosystem level. Immediate, intermediateand long-term likely impacts on all levels ofbiodiversity must be addressed;(b) Criteria should be developed ong>forong> when EIAs46


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversitywould be required;(c) Criteria should also be developed ong>forong> applicationof EIAs on all levels of biodiversity(genes, species, ecosystems);(d) Support the implementation of appropriateenvironmental impact assessment and monitoringprogrammes ong>forong> ong>maricultureong>;(e) Global assessment should also be reinong>forong>ced;(f) Regional and international collaborationshould be supported to address transboundarybiodiversity impacts of ong>maricultureong>, suchas spread of disease and alien species;(g) Development of appropriate genetic resourcemanagement plans at the hatchery level andin the breeding areas, addressed to biodiversityconservation;(h) Development of effective site selection andeffluent control methods ong>forong> ong>maricultureong>;(i) Controlled low cost hatchery and geneticallysound reproduction and making it availableong>forong> widespread use to minimize/avoid seedcollection from nature;(j) In cases where seed is collected from nature,selective fishing gear should be used toavoid/minimize by-catch;(k) Effective measures to prevent the inadvertentrelease of aquaculture species and fertilepolyploids, through methods such as confinement;(l) Use of local species in aquaculture;(m) Avoiding the use of antibiotics through betterhusbandry techniques.3. Future needsThe Expert Group recognizes that at the presenttime, there is insufficient inong>forong>mation availableabout the effects of ong>maricultureong> on biodiversity andits mitigation. Thereong>forong>e, additional efong>forong>ts shouldbe developed along three topics: research, monitoringprograms, policies and legislation.(a) Research1. General research needs:(a) Development of research programs to supportestablishing efficient monitoring programmes(b) Development of criteria ong>forong> judging seriousnessof biodiversity effects(c) Improvement and transfer of integrated ong>maricultureong>systems, including polyculture(d) Monitoring programmes to detect biodiversityeffects(e) Research in the impact of escapees on biodiversity2. Research related to impacts of ong>maricultureong>on genetic diversity:(a) Development of a genetic resource managementplans ong>forong> broodstock(b) Understanding genetic effects of biotechnologydevelopments in aquaculture(c) Understanding genetic structure of both thefarmed and wild populations, including:(i) Effects of genetic pollution from farmedpopulations on wild populations(ii) Maintenance of genetic viability of farmedpopulations(iii) Studies of the genetics of wild populationsas potential new candidates ong>forong> ong>maricultureong>3. Research related to impacts of ong>maricultureong>on species diversity:(a) Support ong>forong> basic global-scale taxonomic47


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversity(b)(c)studies, perhaps in conjunction with theGlobal Taxonomy Initiative (GTI)Support ong>forong> studies aimed at development ofresponsible aquaculture using native speciesLimiting by-catch of seed collection4. Research related to impacts of ong>maricultureong>and ecosystem diversity:(a) Carrying capacity and carrying-capacitymodels ong>forong> planning aquaculture, speciallystocking rates(b) Comprehensive studies should be carried outto quantitatively and qualitatively assesseffects of ong>maricultureong> on biodiversity ong>forong> variousaquatic ecosystems, selected by their sensitivenessdegree.(c) The competitive nature imposed on marinefisheries by capture and culture fisheries(d) Improved understanding of the effects ofinputs, such as chemicals, hormones, antibioticsand feeds on biodiversity(e) Research on impact of diseases in culturedand wild species on biodiversity5. Research related to impacts of ong>maricultureong>,socio-economics, culture, policy and legislation:(a) Comparative studies at legislation, economicand financial mechanisms of regulations ong>forong>ong>maricultureong> activity(b) Development of quantitative and qualitativecriteria to assess ong>maricultureong> impacts on theenvironment according to culture practices(b) Monitoring programmes(a) Support ong>maricultureong>-related disease monitoringprograms at the global level(b) Support the transfer of biotechnologicaldiagnostic tools ong>forong> wide use(c) Update of taxonomic database includinggenetic diversity at the intra-specific level48


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversityANNEX IVCASE STUDIESA. CASE STUDY ENHANCEMENTAND SEA RANCHING1. The idea makes perfect sense: use the tools ofong>maricultureong> to create huge numbers of young animalsthat can be released into the wild at an earlyage, there to feed, grow and add to the fishery. If thefishery is gone they can even replace it, and thetools are so powerful that fry can be produced andreleased in staggering numbers. Why not?2. Enhancement started beong>forong>e the turn of the century,with the rise of the salmon hatchery system inWestern North America, 148 and as methods ong>forong> controlledreproduction and larviculture were developedong>forong> more fish, and then ong>forong> mollusks and crustaceans,those organisms began to be enhanced too.Stock enhancement and sea ranching are now doneong>forong> a wide variety of species in over 70 (generallydeveloped) countries. Enhanced species includeJapanese flounder, Atlantic cod, penaeid prawns,European lobster, scallop, giant clam, abalone andsea cucumber. 149 150 151 In Texas, red drum enhancementhas been successful through a programmethat includes large-scale stocking and managementcontrols on commercial and sport catches, andhabitat protection measures. 152 Each year, NorthAmerican hatcheries release more than 5 billionjuvenile salmon 153 , and school programmes gearedto classroom hatcheries have convinced severalgenerations of children in the Pacific Northwestthat salmon are produced in hatcheries. TheJapanese programme ong>forong> chum salmon is also wellknown, and maintains a consistent fishery targetedlargely on roe (ikura) that has grown from 5 milliontonnes in the 1960s to over 70 million in 1995. 154In fact, most stocks of Pacific salmon in Japanderive from hatcheries, and enhanced chumsalmon are a key component of the Japanese coastalfishing industry.Are there any wild fish left?3. When large numbers of hatchery-bred fish arereleased to the wild there are significant geneticconsiderations, especially as the fish are fullyexpected to breed with “wild” stocks. Such questionsdid not even appear on the radar screens offisheries managers until the past two decades; now,fisheries scientists grapple with them daily in anattempt to establish a role ong>forong> enhancement thatdoes not do outright damage to biodiversity. Therecent Wild Salmon Policy of the Government ofCanada, ong>forong> example, has great difficulty evendefining a “wild” salmon - after so many decades ofwholesale enhancement the introgression of hatcherygenes is assumed to require that a new category,“feral”, be invented. Pacific salmon have endureda combination of insults (overfishing, habitat loss,pollution and change in ocean conditions) thathave collectively severely reduced genetic diversityin the five main species. 1554. The practice of releasing hatchery fish is nowunder criticism ong>forong> threatening native biodiversity(through competition with wild fish or introgressionof hatchery genes), as well as ong>forong> deflectingenergy and resources away from management andhabitat rehabilitation measures that might equallyincrease natural production. Enhancement has also148 Taylor, J. A. 1999. Making salmon: an environmental history of the Northwest fisheries crisis. University of Washington Press.149 Howell, B. R., E. Moksness, and T. Svasand (eds.). 1999. Stock Enhancement and Sea Ranching. Blackwell Science Ltd. Osney Mead, Oxong>forong>d, UK.150 Cowx, I. G. (ed.). 1998. Stocking and introduction of fish. Papers ong>forong>m a symposium held March, 1996. Hull, UK. Okong>forong>d: Fishing News Books.456 pp.151 Bartley, D. M. Marine ranching summary. World Aquaculture Societies Working Group on Stock Enhancement and Sea Ranching Homepage.Available at: http://www.efan.no/was/WAS_ranch.html152 McEachron, L. W., and K. Daniels. 1995. Red drum in Texas: a success story in partnership and commitment. Fisheries 20:6-8. Cited in Smith1999.153 Levin, P. S., and M. H. Schiewe. 2001. Preserving salmon biodiversity. American Scientist 89:220-227.154 Ohnishi, K. Trends in salmon enhancement program in Japan. The Japanese Association of Salmonid Science.http://www.affrc.go.jp:8001/salmonid/sum1/summary.2e.html155 Levin, P. S., and M. H. Schiewe. 2001. Preserving salmon biodiversity. American Scientist 89:220-227.49


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversitybeen attacked ong>forong> simply not working very well andcosting too much. Many stocking programmes donot mark the released fish so that the effect on fisherylandings simply cannot be measured. In fact,very little is known about the behaviour, survival,growth and even genetic impact of enhancedorganisms. Scientists and managers have tended todivide into camps ong>forong> or against enhancement 156 ,with little in the way of data to back up their claims.And environmentalists almost uniong>forong>mly decry thepractice. In North America today, managers try toavoid the term “hatchery” at all, preferring to concentrateon “supplementation”, a technique thatuses the same aquacultural tools but takes pains touse only broodstock representative of local populationswhere in the past a single population mightbe raised and broadcast well outside its nativerange. Technical protocols and methods ong>forong> avoidinggenetic problems with enhancement have beenreviewed ong>forong> some coldwater species 157 158 Generalprinciples and recommendations have been publishedby FAO 159 and codes of practice ong>forong> transferof stock have been drawn up by ICES 160 to beapplied to all enhancement programmes. 1615. The main uncertainties surrounding marineenhancement include:(a) Do hatchery fish really contribute to fisheryproduction?(b) Can the same effect be gained through fishingreduction, habitat restoration or protectedareas?(c) Can the environment support the additionalproduction?(d)(e)(f)Do released fish displace wild stocks?What are the genetic, health and ecologicaleffects of releases?Are the gains cost-effective and ong>sustainableong>?Some unexpected results6. The most obvious and controversial biodiversityquestion - do hatchery fish alter the genetic compositionof wild stocks - is generally answered affirmatively.However, new data gathered with themolecular tools of microsatellite DNA analysis arenot entirely consistent with this conclusion. In ajust-released study of the genetic makeup ofAtlantic salmon in Maine, some unexpected conclusionssurfaced. Maine salmon have beenenhanced since the 1970s, using eggs from localand more distant (Canadian) stocks. River-specificstocking (supplementation) did not start until1991. In addition to this aggressive stocking programme,farming of Atlantic salmon began in the1980s, using European-derived strains that invariablyescaped to breed in the rivers.7. What has been the genetic effect of this concertedaddition of non-native salmon genotypes toMaine rivers? A scientific committee charged withexamining all the available DNA evidence concludedthat wild salmon in Maine are still geneticallydistinct from Canadian salmon, that there is considerablegenetic divergence among populations inthe eight rivers where wild salmon are found, andthat the pattern of genetic variation seen in Mainerivers is similar to patterns seen elsewhere in156 See, ong>forong> example, Wang, Y. L. 1999. Utilization of Genetic resources in Aquaculture: A farmer’s view ong>forong> ong>sustainableong> development. R. S. V. Pullin,D. M. Bartley, and J. Kooiman (eds.). Towards policies ong>forong> conservation and ong>sustainableong> use of aquatic genetic resources. ICLARM Conf. Proc.59. 277 pp.157 Munro, A. L. S. 1988. Advantages and disadvantages of transplantations. Pages 75-83 In E. Grimaldi, and H. Rosenthal (eds.). Efficiency in aquaculture production: disease control. Proceedings of the 3rd Annual International Conference on Aquafarming “AQUACOLTURA ’86,” Verona,Italy. Edizioni del Sole 24 Ore, Milan, 227 pp. Cited in Goldburg.158 Benzie, J. A. H., and S. T. Williams. 1996. Limitations in the genetic variation of hatchery produced batches of giant clam Tridacna gigas.Aquaculture 139:225-241. Cited in Smith 1999.159 FAO. 1993. Expert consultation on utilization and conservation of aquatic genetic resources. FAO Fisheries Report No. 491. FIRI/R49. FAO,Rome, Italy.160 ICES. 1996. Report of the working group on introductions and transfer of marine organisms. ICES C.M. 1996/ENV:8. http://sgnis.org/publicat/papers/skora.pdf161 Smith, P. 1999. Genetic resources and fisheries: policy aspects. Pages 43-62 In R. S. V. Pullin, D. M. Bartley, and J. Kooiman (eds.). Towards policies ong>forong> conservation and ong>sustainableong> use of aquatic genetic resources. ICLARM Conf. Proc. 59. 277 pp.50


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversitysalmon where no stocking has occurred. The committeeconcluded that Maine salmon populationswere as genetically distinct from Canadian salmonpopulations and from each other as would be expectedin natural populations anywhere else. 1628. Clearly, more such studies are called ong>forong> beong>forong>e thepros and cons of enhancement are sorted out. Mainesalmon may be an anomaly, the data may be insufficient,or enhancement may turn out to be more greythan the black in which it is currently painted. Thegenetic stakes, and the costs, certainly justify moreresearch.B. CASE STUDY SHRIMP FARMING9. Nearly one third of all shrimp production is nowfarmed, despite the fact that shrimp farming is a relativelynew industry. Half the production is based onone species, Penaeus monodon, and South-East Asiaand the Americas account ong>forong> three-quarters of worldproduction. 16310. Development of the industry has been volatile.Chinese production, once the leader, failed catastrophicallyin 1993 and has been rebuilding sincethen. Taiwan was one of the top producers in the late1980s but is now a net importer. The practice ofintensive shrimp farming is also politically charged:an Indian Supreme Court ruling closing down coastalintensive farming in the mid-1990s because of environmentaland social effects was superseded by subsequentlegislation.11. Present shrimp production technology has beenstrongly criticized as unong>sustainableong>, with high pricesencouraging overloading of the environment’s abilityto provide clean water and absorb wastes. Export-orientedshrimp culture was encouraged by manyGovernments, often supported by external aid, andenvironmental planning took a back seat. Henceponds were poorly sited, often in mangrove areas andaltering the ecological functions; freshwater aquiferswere overused; coastal areas, lagoons and creeks wereoverloaded with wastes; seed and broodstock werereduced by collection; and disease outbreaks becameepidemic to the point where it became extremely difficultto find pathogen-free seed or broodstock. 16412. All of the ong>forong>egoing impacts have direct or indirectrelevance ong>forong> biodiversity. What progress hasbeen made in reducing them?Mangrove-friendly culture13. From an ecosystem perspective, the role of mangrovesis especially important. Mangroves reduceerosion and serve as spawning and nursery habitatong>forong> many species of fish and shrimp. 165 Loss of mangrovesbecame so serious, both biologically and economically,that world attention has focused on theissue within the past decade, and there are nowstrong signs of an emergent mangrove-friendly ong>maricultureong>industry. This initiative, presently experimentaland confined to ASEAN countries, involvesthe combination of silviculture (reong>forong>estation) withculture of fish, crabs or shrimp and is an attempt to162 National Research Council. 2002. Genetic status of Atlantic salmon in Maine. Interim report from the Committee on Atlantic Salmon in Maine.National Academy Press. Washington, DC. ISBN 0-309-08311-7.163 Yap, W. G. Shrimp culture: a global review. ASEAN-SEAFDEC. The world of mangroves, mangrove-friendly shrimp culture. http://www.mangroveweb.net/html/ffarming.htm164 Barg, U., R. Subasinghe, R. Willmann, K. Rana, and M. Martinez. 1999. Towards ong>sustainableong> shrimp culture development: implementing theFAO Code of Conduct ong>forong> Responsible Fisheries (CCRF). Pages 64-81, In B. W. Green, H. C. Clifong>forong>d, M. McNamara, and G. M. Montaño (eds.).Central American Symposium on Aquaculture, 18-20 August, 1999. San Pedro Sula, Honduras. Asociación Nacional de Acuicultores deHonduras (ANDAH), Latin American Chapter of the World Aquaculture Society (WAS), and Pond Dynamics/Aquaculture CollaborativeResearch Support Program (CRSP), Choluteca, Honduras. Available at: http://www.fao.org/fi/faocons/shrimp/honduras.asp#F1165 Josupeit, H. 2000. Environmental issues of warmwater prawns. Presented at Coldwater Prawn Forum, 22-23 June, 2000. Edinburgh, UK. FAOGLOBEFISH. http://www.globefish.org/index2.htm51


ong>Solutionsong> ong>forong> ong>sustainableong> ong>maricultureong> - avoiding the adverse effects of ong>maricultureong> on biological diversitydevelop and disseminate responsible culture technologies.166 Mangroves are also being promoted asenvironments ong>forong> culture of mud crabs in pens, atechnique that eliminates the conversion of coastalareas to ponds. In the Philippines, crab farming intidal ponds is already an established industry andcrab farming in mangrove areas shows enormouspotential. However, the seed crablets come from thewild. It is important to develop and refine breeding,hatchery, and grow-out technologies in orderto realize their potential to become a cash crop andexport industry in tropical Asia without adverseenvironmental impact. 167Controlled reproduction reducesthe need ong>forong> wild fry14. The difficulty of collecting fry, especially disease-freeones, led to the rapid development ofmethods ong>forong> controlled reproduction, a significantresearch investment. Now, in countries with welldevelopedshrimp farming industries, reproductionis largely controlled in the laboratory, usingeyestalk ablation techniques to induce spawning incaptive broodstock. There is even a research efong>forong>tto develop gene-banking technology ong>forong> shrimpgametes and embryos, to ensure a steady supply ofpathogen-free seed.Better than the alternative?15. The shrimp culture industry, with its spectacularsuccesses and dismal environmental failures,provides a model ong>forong> the intervention of States indeveloping codes of conduct ong>forong> responsible practices.FAO in particular has been working hard inrecent years to implement the principles of theCode of Conduct ong>forong> Responsible Fisheries, assisting,ong>forong> example, in development of national codesof practice and technical guidelines. 168 That this isworth doing from a biodiversity standpoint is notsimply a matter of protecting mangrove ecosystemsor reducing pressure on wild larvae. The wildshrimp fishery, a bottom fishery that uses geardragged over the sea floor, is notoriously one of themost destructive fisheries in the world. By-catch,the capture of unwanted species, exceeds shrimpcatch by the huge factor of six to one, meaning that12 million tonnes of unwanted organisms arecaught every year, two-thirds of which is thrownback dead. The benthic community is seriouslydamaged by trawling, and the overall effect onmarine ecosystems may be profound. The depredationsof the wild shrimp fishery are probably thelast thing on the mind of farmers, but there is astrong argument to be made that a ong>sustainableong>farming industry could reduce not only the pressureson the wild stocks but also the collateral biodiversitydamage caused by trawling.166 Aalvik, B. Production of Atlantic salmon and rainbow trout in Norway, preventive health care. Cultivation of Salmon II Conference. Bergen,Norway, May 7-10, 2001. Abstract available as pdf file at: http://www5.imr.no:8080/salmon/innhold.htm167 SEAFDEC - Aquaculture Department of the Philippines. http://www.seafdec.org.ph/home.html168 Barg, U., R. Subasinghe, R. Willmann, K. Rana, and M. Martinez. 1999. Towards ong>sustainableong> shrimp culture development: implementing theFAO Code of Conduct ong>forong> Responsible Fisheries (CCRF). Pages 64-81, In B. W. Green, H. C. Clifong>forong>d, M. McNamara, and G. M. Montaño (eds.).Central American Symposium on Aquaculture, 18-20 August, 1999. San Pedro Sula, Honduras. Asociación Nacional de Acuicultores deHonduras (ANDAH), Latin American Chapter of the World Aquaculture Society (WAS), and Pond Dynamics/Aquaculture CollaborativeResearch Support Program (CRSP), Choluteca, Honduras. Available at: http://www.fao.org/fi/faocons/shrimp/honduras.asp#F152


ALSO AVAILABLEIssue 1:Issue 2:Issue 3:Issue 4:Issue 5:Issue 6:Issue 7:Issue 8:Issue 9:Issue 10:Issue 11:Review of The Efficiency and Efficacy of Existing Legal Instruments Applicableto Invasive Alien SpeciesAssessment and Management of Alien Species that Threaten Ecosystems, Habitatsand SpeciesAssessment Conservation and Sustainable Use of Forest BiodiversityThe Value of Forest EcosystemsImpacts of Human-Caused Fires on Biodiversity and Ecosystem Functioning, andTheir Causes in Tropical, Temperate and Boreal Forest BiomesSustainable Management of Non-Timber Forest ResourcesReview of the Status and Trends of, and Major Threats to, Forest BiologicalDiversityStatus and trends of, and threats to, mountain biodiversity, marine, coastal andinland water ecosystems: abstracts of poster presentations at the eighth meeting ofthe Subsidiary Body on Scientific, Technical and Technological Advice of theong>Conventionong> on Biological DiversityFacilitating Conservation and Sustainable Use of Biological DiversityAbstracts of poster presentations on protected areas and technology transfer andcooperation at the ninth meeting of the Subsidiary Body on Scientific, Technicaland Technological AdviceInterlinkages between Biological Diversity and Climate ChangeAdvice on the integration of biodiversity considerations into the implementationof the United Nations Framework ong>Conventionong> on Climate Changeand its Kyoto ProtocolStatus and Trends of Biodiversity of Inland Water Ecosystems

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