a uacu ture in. t enext centu opportunities for growth challenges of sustainability George Chamberlain Harald Rosenthal In the last decade, aquaculture has been the only growth sector within fisheries and the prospects for continued growth appear excellent. Global per capita seafood consumption has been rising steadily since 1969, but landings from the capture fisheries reached a plateau in 1989, leaving aquaculture as l -i., the primary source of seafood production to meet this increasing demand. A substantial portion of the global increase in aquaculture production has come from coastal en­ I vironments, but as the human population grows and I I! expand~ its involvement in the coastal zones, there i will be increasing pre~sure to share the coastal I t resources among multiple users. In this environment some of our existing aquaculture practices will not be sustainable in their present form, but those that are designed to accommodate multiple resource use could grow rapidly. Examples range from the tradi­ tional farming systems in Southeast Asia, which benefit the community at large as well as the aquaculturists themselves, to modern high-tech re­ circulation systems. World Aquaculture 26( 1) March 1995 21 s the aquaculture industry As the population expands, air, water, lamination by aquaculture species grows, conflicts over water use and land pollution will become more. These steps will protect the environ will "intensify and competition severe. Controls will be necessary to menl and safeguard the aquaculture in A mitigate the greenhouse effect, acid dustry. will develop among users of the limited coastal resources. rain, toxic waste accumulation and eu­ These anticipated restrictions shoull At the recent AQUATECH '94 Confer­ trophication of coastal waters, and be viewed by the aquaculture industr·. ence in Sri Lanka, Imre .Csavas of the aquaculture operations surely will face not as constraints to development but;.; Regional FAO Office in Bangkok pro­ increasingly stringent discharge regula­ challenges wherein a4uaculture ma· jecteJ global seafooJ demand and tions. Not even recirculating systems find new opportunities. Scenarios ca; aquaculture production."> Demand was will be immune, because the solid waste be envisaged where the aquaculture in . calculated by multiplying human popu­ they generate (about 0.4 kg per kg of duslry could become a stabilizing ele lation projections by expected per capita product) will be subject to regulation. ment in an integrated, ecosystem-ori ­ seafood consumption. According to the The aquaculture industry has recently ented production strategy. UN, the human population of 5 billion in 1990 will increase to 8 billion by . Resource 2025. By assuming that global per cap­ management failures ita seafood consumption would remain close lo the current level of 14 kg for the Sustainability will become a familia next 30 years, Csavas calculated that term to those of. us in the aquaculturt seafood demand in the years 2000, The capture industry. The concept, simple and intui­ 2010, and 2025 would be 84, 97 and 115 tive, refers to management practices tha, million tonnes, respectively.<'> fisheries of the will not degrade the environment. Sus­ Fisheries landings peaked in 1989 at tainability models were developed a5 89.7 million tonnes and have since fluc­ early as 1849<3> to maximize economic tuated near this level, indicating the · world are benefits from forest management. The world fisheries stocks are being har­ outcome of efforts to manage open ac ­ vested at close to their maximum sus­ being · cess resources such as marine fisherie: tainable yield. Market demand for and common property resources such a: aquaculture products can be expected to forest and irrigation systems has beer increase as fisheries output stabilizes. harvested at dismal, and it has been argued that these The human-food portion of this fisher­ failures were due to conflicting desire'. ies harvest is some 69 millj on tonnes, so close to their to satisfy unlimited consumption witr aquaculture demand should be close to limited resources. (3) In the face of uncer 22-24, 35-37 and 52-55 million tonnes • tainty, managers often err on the side o, in the years 2000, 2010, and 2025, re­ maximum the exploiting industry rather than the spectively.0·2> However, aquaculture resource. The tendency is to base har· may be unable to service this demand, sustainable vest levels for a resource on periods o: and shortfalls could range from 1-3 mil­ high production rather than periods 0° lion tonnes in the year 2000 to 9-13 yield. , low production. In other words, an esti· million tonnes in 2025. mate of Maximum Sustainable Yielc tends more toward "maximum" thar Impending "sustainable." changes Ludwig and colleagues<4> likened the exploitation of fluctuating resources tc Aquaculture is entering a new era, one experienced several spectacular failures a ratchet. During good years the harves in which resource and environmental due to disease outbreaks. In some cases, quotas are increased, which encourage concerns will play a much larger role in practices that contributed to the impres­ new investment. Then, when the re decision making. Although human sive growth of the industry (e.g., the source returns to normal or below, the population increase will create a grow­ shrimp culture strategies used in Thai­ industry appeals to the government fo ing market for aquaculture products, it land, China and Taiwan) profited help. Since jobs and investment are .a will also generate competition for scarce · through the unilateral exploitation of re­ stake, government subsidies are mad, natural resources and accelerate envi­ sources and, therefore, thrived at the available. This combination results ir ronmental degradation because, unfor­ expense of others. If modern aquacul­ the stock being continually overhar tunately, per capita consumption of re­ ture is to survive, it will have to become vested. sources is also increasing. Groundwa­ more compatible with other users of re-· Resource management issues are nc ter, land, feed, and energy resources are sources and with the environment. easily resolved by science. Even simph likely to become more highly valued Tighter regulations will be needed to ecosystems can not yet be predicte, and tightly regulated. Aquaculture prac­ prevent, for example, introduction and with confidence, and significant ne\ tices that are wasteful of resources will transmission of disease organisms. Ad­ knowledge accumulates slowly. In ac not be sustainable in the face of these ditional regulations may be needed to dition, political and economical factor shortages. protect native organisms from intro­ must be considered, and these are ofte, duced diseases and from genetic con- more fundamental than the scientific is 22 March 1995 World Aquaculture 26( 1 ,; 125 PROJECTED SE~FOOD DEMAND Projected demand for food D Aqu1cultur• 114.1 grade seafood (industrial U) c 100 • Cipturc fl1hcrlc1 fish and seaweed excluded), ...0 97.2 assuming plateau of capture 0 ·.::... 8/t.5 fisheries at 60 million ton­ Cl.I 75 E nes (adapted from Csavas(t)J c ~ 50 ~ 25 an integrated, interdisciplinary, mul­ tisectoral approach in the development of management plans for these coastal areas.00., 1> 1992 2000 2010 2025 To promote sustainable economic de­ YEAR velopment in the ASEAN region, a pro­ ' gram was initiated to develop Coastal Resource Management (CRM) strate­ sues. Scienc.e can advise the political type is a comprehensive plan to control gies. This goal can be achieved by: process about what is physically and resource use.<5> •documenting and disseminating in­ biologically possible, but the final deci­ formation on the ways that coastal re­ sions must balance these considerations Conflicts and sources are being developed for eco­ against conflicting political and eco­ management plans nomic purposes; nomic interests. •suggesting technical approaches to Conflicts concerning aquaculture use the resolution of conflicts arising from Accountabl!ity of natural resources are likely to arise multiple use of the coastal resources, more frequently in the future. It is im­ including aquaculture; and One fundamental lesson that emerges portant that aquaculturists anticipate •encouraging various agencies to adopt from the history of failures in resource these issues and help find solutions. All multisectoral planning in coastal areas. management is that lack of user account­ stakeholders should be involved in the In this context, aquaculture is an inte­ ability leads to resource failure. Resources decision process. In some enlightened gral part of the development and man­ suffer the tragedy of the commons: that areas, this process is already underway. agement plan, and many of the issues which belongs to all is cared for by none. For example, the National Aquaculture will have direct implications for The world fishery stocks will not be re­ Association of Honduras (ANDAH) is aquaculture. In many regions aquacul­ stored until harvest limits are defined and working to avoid environmental and · ture has been promoted without ade­ rigorously enforced. In some areas, ac­ pollution problems in the Gulf of Fon­ quate consideration of site selection cri­ countability has been established by re­ sec, an estuarine system with limited teria and the interactions that are likely stricting access and allocating individual tidal flushing, by supporting a self-lim­ to occur with other resource users. How­ transferable quotas, but this is a disputed iting moratorium on expansion