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Suggested Citation:"Overview." National Research Council. 1988. Fisheries Technologies for Developing Countries. Washington, DC: The National Academies Press. doi: 10.17226/1024.
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Suggested Citation:"Overview." National Research Council. 1988. Fisheries Technologies for Developing Countries. Washington, DC: The National Academies Press. doi: 10.17226/1024.
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Suggested Citation:"Overview." National Research Council. 1988. Fisheries Technologies for Developing Countries. Washington, DC: The National Academies Press. doi: 10.17226/1024.
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Suggested Citation:"Overview." National Research Council. 1988. Fisheries Technologies for Developing Countries. Washington, DC: The National Academies Press. doi: 10.17226/1024.
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Suggested Citation:"Overview." National Research Council. 1988. Fisheries Technologies for Developing Countries. Washington, DC: The National Academies Press. doi: 10.17226/1024.
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Suggested Citation:"Overview." National Research Council. 1988. Fisheries Technologies for Developing Countries. Washington, DC: The National Academies Press. doi: 10.17226/1024.
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Suggested Citation:"Overview." National Research Council. 1988. Fisheries Technologies for Developing Countries. Washington, DC: The National Academies Press. doi: 10.17226/1024.
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Suggested Citation:"Overview." National Research Council. 1988. Fisheries Technologies for Developing Countries. Washington, DC: The National Academies Press. doi: 10.17226/1024.
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Suggested Citation:"Overview." National Research Council. 1988. Fisheries Technologies for Developing Countries. Washington, DC: The National Academies Press. doi: 10.17226/1024.
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Suggested Citation:"Overview." National Research Council. 1988. Fisheries Technologies for Developing Countries. Washington, DC: The National Academies Press. doi: 10.17226/1024.
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Suggested Citation:"Overview." National Research Council. 1988. Fisheries Technologies for Developing Countries. Washington, DC: The National Academies Press. doi: 10.17226/1024.
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Suggested Citation:"Overview." National Research Council. 1988. Fisheries Technologies for Developing Countries. Washington, DC: The National Academies Press. doi: 10.17226/1024.
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Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Overview Many of the fishermen in developing countries are locked into economic systems that result in relative poverty. Although the technologies they use have evolved in accord with indigenous bi- ological resources and socioeconomic realities, there may be op- portunities for improvement. Existing technologies from other de- veloping regions might be transferred to these fisheries and some of the technological advances from industrialized countries might benefit artisanal fishermen. This report describes some of these innovative fishing tech- nologies for small-scale fishermen, administrators of fisheries, de- velopment assistance groups, and others concerned with fisheries. The objective is to establish new contacts, to examine alterna- tive fishing technologies, and, after careful planning, to encourage application in new areas. SMA[L-SCALE FISHERMEN There are about 15 million traditional small-scale fishermen in the Third World, perhaps half of whom fish full time. Another 15 million people are involved in fish preservation and distribution. Assuming an average family of six, close to 200 million people in poorer countries are dependent on small-scale fisheries. For these 1

2 FISHERIES TECHNOLOGIES FOR DEVELOPING COUNTRIES people and the many others whom they supply, fish caught by traditional methods represent their principal source of protein. Traditional fisheries may be commercial or subsistence, but they each have in common a small cash income. Fishermen of this sector often live In isolated coastal villages and may also be engaged in susbsistence agriculture. In many societies, artisanal fishermen occupy the lowest social and economic class. The fisherman's main wealth is in his fishing gear (boats, motors, nets, and lines), which is subject to rapid depreciation and loss. Fishermen either construct their own boats and assemble their gear or purchase them from village experts. In some cases, their small boats are powered with outboard gasoline motors, although sail and paddle power are cornrnon. Fishing practices tend to be labor intensive with minimal mechanical assistance. The total investment in fishing equipment is generally quite low, and the artisanal fisherman is quite adept at minimum input management. Fishing productivity in the artisanal sector is consequently variable and low; many fishermen catch only one or two tons of fish per year. Nevertheless, the fish catch per ton of fuel con- sumed is much higher than in the industrial sector. The catch is rarely distributed in organizer} markets; more often it goes to local markets or is consumed by the fishermen's family. PROBLEMS OF SMALI~SCALE FISHERMEN Artisanal fishermen face a series of difficulties that contribute to their marginal standard of living. Government fishery policies often tend to concentrate resources in the modern, large-scale, commercial fisheries that earn foreign exchange. Thus, the small- scale fisherman finds it difficult or impossible to obtain credit, extension services, marketing assistance, or similar aid from de- velopment programs. Traditional fishermen often compete with the industrial sector over limited common resources in the exclusive economic zone and commonly lose against more efficient technologies. Numerous con- flicts between these two types of fisheries occur. Typically, trawlers enter areas used by artisanal fishermen, destroying spawning and feeding areas, and damaging their buoys, nets, and traps. Further, the by-catch from inshore shrimp trawlers is often discarded, both

OVERVIEW 3 removing the resource from the small-scale effort and decreasing the availability of protein. In many coastal zones, overexploitation of marine resources is already a serious problem that is augmented by low productivity. It heightens the conflicts between the industrial and traditional fisheries and endangers the economic and nutritional status of people who rely on the traditional fisheries. Fish stocks may also be depleted by pollution from urban areas, industry, or mining; this more seriously affects small fisher- men who have only limited mobility. Mangrove destruction, which removes vital spawning grounds, Is also detrimental to coastal fish stocks. In addition to biological overfishing and stock depletion, eco- nomic overfishing often plagues the small-scale sector. Excessive use of boats, fuel, and gear may double the effort needed to catch a limited amount of fish. Market access is impeded by lack of credit, capital, and trans- portation. Moreover, the small-scale fishermen's lack of organiza- tion precludes them from influencing the market. The unavoidable dependence on middlemen for the means of production and mar- keting is often a great liability. ~ other situations, the artmanal fisherman's reliance on less than optimal fishing vessels, methods, and gear may limit his catch, especially when he is competing with the industrial sector. The lack of adequate landing and processing facilities exacerbates heavy losses from wastage and makes selling fish outside the local area difficult. Boat construction ~ a growing problem for many fishermen. The traditional dugout canoe, proa, and catamaran used for fishing and marine transportation require high-quality hardwood. With deforestation of many tropical coastal areas, these strong, work- able, long-lived woods are increasingly scarce. Many artisanal fishermen have adopted outboard motors, and sail technology has fallen into disuse. Outboard gasoline motors are expensive, difficult to repair, and not fuel efficient. Their costs can seriously restrict fishing operations. In West Africa, the lack of foreign exchange to purchase spare parts, replacement motors, and fuel has resulted in a decrease in the percentage of motorized small-scale fishing boats.

4 FISHERIES TECHNOLOGIES FOR DEVELOPING COUNTRIES INNOVATIVE TECHNOLOGIE:S While recognizing the diverse problems faced by the small- scale fisherman in the Third World, this report will prunarily address technological considerations. Innovative, relatively inex- pensive technologies that, under some circumstances, might help fishermen will be described. Although not necessarily the newest, most sophisticated developments, these techniques may have al- ready found successful application ~ a specific region. A tech- nology might be successfully adapted to a new area if it solves a specific problem, causes no ecological or social problems, and is economically feasible and desired by the community it is intended to serve. Successful applications of new mechanical or fabrica- tion technologies also require training, service support, and locally available components and spare parts. There are no universal answers in fisheries technologies. Each fishery should be studied individually to determine the technolo- gies that are applicable to its specific conditions. Boats Traditional fishing vessels are highly adapted to the fishing techniques and marine conditions of a specific region. This coor- dination between structure and function is not without problems, however. Small fishing boats often have a limited range of op- erations and are unsafe. They may lack structures to store and protect the catch. The high-quality timber used for boat construc- tion in many tropical areas is increasingly scarce. Thus, in some regions there may be a stimulus for modifications in vessel design and construction materials. High-quality timber and planks may be replaced by laminated wood composites (plywoods) preserved and sealed with resins. Plywood pieces can be wired together with galvanized soft-iron wire and then sealed with epoxy resins in the "stitch-and-glue" technique. Plywood boats are strong and light and are used in many parts of the world. New construction techniques use veneers or thin plywood strips to build up a laminated hull over a mold. The veneer layers are oriented diagonally to each other and glued with epoxy resins. Plywood or fast-growing woods can be used in these rapid- construction methods.

OVERVIEW 5 Rafts made from plastic tubes have become widely accepted in Taiwanese coastal fisheries, as have ferrocement vessels in Cuba and China. Fiberglass is another increasingly popular material for boat construction because of its light weight, longevity, and strength. The United Nations Food and Agriculture Organization's Bay of Bengal program has adapted a fiberglass version of the traditional vu, a wooden outrigger. A number of fiberglass modifications of traditional West African fishing vessels have also been designed by the Yamaha Motor Company of Japan. Alternative hull forms have gained popularity in some regions. Multihulled vessels or outriggers, traditionally found in the South Pacific and Southeast Asia, offer certain advantages for small-scale fisheries: they are stable, can be beached, and have a large working deck. The outboard gasoline motor, widely used in small-scale fish- eries throughout the world, is not very fuel efficient. Fuel is expen- sive, a high level of maintenance is required, and spare parts are scarce. Fishing vessels are frequently overpowered and waste fuel, in part because of the fishermen's desire for high speed to increase their range or competitiveness. Fuel savings can be achieved by employing more efficient mo- tors or using alternative fuels. Diesel-powered outboard and in- board motors have longer lifetimes than their gasoline counterparts and may be more economical. However, their high initial cost may be prohibitive to the small fishermen. Gasifier technology has been developed in the Philippines and applied to fishing boats. Charcoal is burned with limited oxygen supply to produce a gaseous mixture of hydrogen, carbon monox- ide, and methane, which can be used to fuel gasoline engines. Steam engines are also being investigated as power sources for small boats. The oldest propulsion technique, wind power, is being reintro- duced in a number of small-scale fisheries. Sails may be used as the main means for propulsion or to assist an engine. Fishermen can take advantage of the winds, thus saving fuel and reducing operating costs. Having an alternative propulsion source also in- creases the crew's safety. The details of sail-assist are specific for each fishery, since marine conditions, fishing vessels, and methods all vary. The sails may be constructed of very inexpensive materials,

6 FISHERIES TECHNOLOGIES FOR DEVELOPING COUNTRIES such as canvas bags or the plastic sheeting used by kattumaran fishermen in Southern India. These sails last for many months, and can be easily repaired or replaced. The Bay of Bengal program in India and Sri Lanka has rein- troduced sailing rigs to small fishing vessels with positive results. A great deal of work has also gone into fitting sails to West African fishing canoes. The high stability of catamarans permits them to carry larger sail areas than equivalent monohulb. Experunental fishing cata- marans using sails have been adopted in India, West Africa, and the South Pacific. Fishing Methods and Gear The time-tested fishing methods are usually ideal for a given region since they have evolved to best fit such local requirements as the species to be captured and the desired size, the type of coast, and the marine conditions. Changing conditions may dic- tate new approaches, however. Modernizing factors are always a consideration for every traditional fishing method or gear. More- over, successful fishing arts could be transferred from one region to another if conditions were comparable. There are numerous examples of innovative fishing arts being used in the Third World that are unknown several hundred miles away. New technologies could tap previously unexploited resources or allow small-scare fishermen to compete more effectively with the industrial sector. Longlines, successfully used in many areas, offer great po- tential for the small-scale fishermen. These unwatched lines with multiple hooks attached to branch lines (snoods) may be set ver- tically or horizontally and can be anchored or allowed to drift. Modernization of this art involves the mechanization of hauling, the use of detachable snoods and polyethylene lines that float just off the bottom, and the introduction of light-emitting lures, which may help to increase the catch. Pots and traps are universal and have the advantage of low cost and minimal inputs. They are highly specific to species and sizes, and their placement requires knowledge of the local conditions. Modernization in these fisheries is manifested by the use of more durable construction materials than traditional woods and fibers. Thus, modern Japanese octopus pots are constructed of sections

OVERVIEW 7 of PVC pipe. Loss of traps or pots can be minimized by attaching them to longlines or by installing time release devices (po~ups). Light attraction of fish could be employed in many parts of the world. It is now used on Lake Tanganyika to attract fish to the opening between the two hubs of a catamaran. A liftnet captures the fish after they have been concentrated. In the Caspian Sea, light is also commonly used to attract fish to liftnets. Trawling is a fishing technique usually restricted to indus- trial fisheries. However, two small boats with 5-hp motors can pair trawl, pulling the net together and thus compete with larger trawlers for benthic species. Artificial Reefs Fish concentrate around submerged objects such as reefs, rocks, logs, and harbor structures. Fishermen have observed this and built artificial underwater structures to concentrate fish stocks. Artificial reefs are common in many traditional fisheries. Modern technologies may provide durable materials for these structures, but their function remains the same. Artificial reefs can be used as effective management took. By concentrating the fish crop, fishermen can save time and fuel, thereby facilitating the catch. Bundles of brush are placed in secluded coastal areas in West Africa, Cuba, and the Philippines to provide shelter and spawning areas for fish. Lobster shelters made of mangrove branches are prevalent in the lobster fisheries of Cuba and the Yucatan in Mex- ico. Traditional Japanese artifical reefs employ rock and rubble to enhance fishing grounds. Tires and cement are common materials for artificial reefs in Taiwan, the United States, and Israel, whereas the Japanese invest in sophisticated fiberglass, concrete, and steed modules. Thailand's Department of Fisheries conducts an artificial reef program whose objective is to enhance fishing grounds for artisanal fishermen. Concrete trawler exclusion modules, which damage trawling nets of industrial fisheries, have also been deployed. Artificial reefs are placed on the sea floor; fish aggregating devices (FADS) are used at the surface or suspended in the wa- ter column to attract pelagic species. Japanese fisheries employ floating bamboo shelters to attract dolphin fish or tuna. Philip- pine payaos are tuna-attracting bamboo rafts with p aim fronds

8 FISHERIES TECHNOLOGIES FOR DEVELOPING COUNTRIES that are anchored in deep water. Modern FADs are constructed of steel, plastic, and artificial fibers, and may be more durable than traditional structures. Nevertheless, they are easily lost in the marine environment. Coastal Mariculture Mariculture offers an alternative to the overexploited marine resources in many coastal regions. It is possible that some fishing communities could also become involved with sea farming to pro- vide additional protein or income. Sea farming in underutilized coastal areas would not compete with terrestrial agriculture for space and could be implemented without large investments. This report will only address mariculture in the coastal ocean, not the much larger topic of pond cultivation. Recent research by the Smithsonian Institution has shown the biological feasibility of algal turf mariculture in nearshore areas. Algal turfs are grown on screens and then fed to herbivores such as whelk, parrotfish, and crab. Highly nutritious seaweeds are consumed in Asia and are also employed in industry. The red algae Eucheuma is cultured on monofilament nets on family farms In the Philippines. The edible kelp Laminaria ~ cultivated on longlines and floating rafts in China. Nori (Porphyra), a popular edible seaweed, is farmed on submerged nets in Japan. Cage culture of marine fish is still in its infancy but will undoubtedly gain popularity. The cages protect the fish from predators and simplify harvesting. The limited space available to the fish ensures that they will convert feed efficiently. Crustaceans and molluscs are widely cultured in the marine environment. Oysters, mussels, clams, and scallops are typically grown on lines, stakes, or on the bottom, in many parts of the world. The highest productivity of these animals is in off-bottom culture. Good yields of mussels have been obtained in Western Samoa. The giant clam Trifdacna displays a rapid growth rate and has demonstrated good potential for mariculture in the Caroline Islands. Integrated sea farms have been established in Indonesia and the Philippines. Houses are built on bamboo stilts over the pros tected reef flat where sea farmers culture seaweed, shellfish, and fish.

OVERVIEW 9 Fib Processing Approximately 35 percent of the worId's fish catch is lost after harvesting. These losses are great in the small-scale fisheries in tropical countries. Simple preservation techniques, common in one area of the world, could be employed in others to reduce postharvest losses. Icing is a preferred preservation technique, but since it requires gasoline or electricity, it is often expensive. The Asian Institute of Technology In Thailand has field-tested an ice-making machine that uses solar energy. Wind and biomass energy may also run refrigeration systems. Fish may be salted by dry or wet methods, although the latter (brine and pickle) are best for tropical applications. Numerous solar driers are in use throughout the tropics. They exclude insects and develop high enough temperatures to reduce mold or bacterial spoilage. Black plastic lining in the chamber absorbs heat and initiates a flow of heated air through the drier. Improved smokers, such as the Chorkor smoker, are gaining acceptance In West Africa. They have long lives, low construction costs, consume little firewood, and have a large fish capacity. Other processing methods have been perfected in specific re- gions. Minced fish (surimi) is the starting material for a number of fishpaste products in Japan. Kamaboko—the use of cheap fish flesh for reconstituting textured marine product analogs (such as crab legs, shrimp, and lobster meat) is becoming more widespread, acceptable, and profitable. Boiling fish in water is a short-term preservation technique practiced in Southeast Asia. Fermented fish products, such as sauces and pastes, are common in South and Southeast Asia. LIMITATIONS This report treats fishing technology alone, as if it were iso- lated from biological, economic, cultural, and political considera- tions. The constraints of the small-scale fisherman in the Third World are usually socioeconomic and rarely due simply to the absence of a specific technology. Those who are involved in the introduction of technologies must be sensitive to the complete

10 FISHERIES TECHNOLOGIES FOR DEVELOPING COUNTRIES environment of the fisherman. Some of these interconnected con- siderations influencing the transfer of fishing technology include biological, economic, and social factors. Biological Factors Before any innovative marine technology is introduced, the marine resources to be exploited should be identified and assessed. Their temporal and spatial distribution, population dynamics, behavior, and life history should all be known. Sufficient stocks must be available to support the increased fishing effort. At present, many coastal marine species are biologically over- fished by the existing technologies. If this is the case for the fishery in question, there is certainly no need to introduce more efficient fishing technologies that would further exceed the maximum sus- tainable yield. A new technology will create an impact on the fish stocks. The magnitude of the impact should be determined so that effective management programs could be revised or initiated. Economic Factors The introduction of new technologies involves investment of capital. Artisanal fishermen will only embrace and continue to use new technologies that satisfy their own economic interests. Any increased capital, or operating or maintenance costs must be balanced by an increased catch, which translates into increased profit. Careful cost-benefit analyses, feasibility studies, and pilot projects must be undertaken to ensure that this is the case. The new technology must also be carefully compared with and evaluated against current technologies to ascertain that it Is more successful and is worth the increased investment. If it is determined that there is an overinvestment in boats, gear, and fuel (economic overfishing), it may not be wise to introduce a new technology. Most small-scale fishermen operate with an economic phi- losophy of minimal input management. That is, they invest as little as possible and hope for a maximum return. This method of operation must be understood by those working in fisheries development. Credit must be available to the artisanal fishery sector with

OVERVIEW 11 conditions of financing that are culturally acceptable and econom- ically reasonable for the fisherman. The specific situation would determine the most appropriate structure for extending credit and whether the primary beneficiary of the credit is the individual fisherman or a fishing cooperative. The regional economic stituation must be considered in addi- tion to the economics of the new technology. It must be determined whether the processing and storage, transportation, and market- ing infrastructure are adequate to handle an increased catch. Social Factors The successful introduction of technology requires a keen un- derstanding of the cultural intricacies of a society. A technological innovation or modernization must be compatible with the existing social organization and managerial level if it is to be adopted by the community. The community's concepts of ownership of pri- vate property and tenure of the marine resources must be clearly understood by outsiders who are working in fisheries development. The social implications of the new technology must also be carefully considered. Perhaps there wall be conflict and competi- tion with fishermen who continue to use the old technologies. Sig- nificant income disparities might be introduced into a close-knit, egalitarian community. Alternatively, social stratification could be exacerbated if only the wealthier fishermen were to benefit from the new technology. A new capital-intensive technology could also require less manpower and create unemployment. Since technol- ogy implies knowledge and knowledge translates into power, there could be significant power shifts in the commmunity as a result of the introduction. It must be determined if the community's social fabric is re- silient enough to withstand these increased tensions or if, perhaps, the increased social stress caused by the technology would negate its benefits. The successful acceptance of a new technology by small-scale fishermen will depend on the participation of the fishermen in the choice of technology, their belief in its economic feasibility, the manner of its introduction, the technology's demonstrated success, and its modification to meet the unique local conditions.

12 FISHERIES TECHNOLOGIES FOR DEVELOPING COUNTRIES SELECTED READINGS Ben-Yami, M. 1984. 33~103:5-6. Ben-Yami, M. 1984. Technology transfer. World Fishing 33~93:4-5. Ben-Yami, M., and A. M. Anderson. 1985. Community Fishery Centers: Guidelines for Establiahmcnt arid Operation, FAO, Rome, Italy. Compte, M.C. 1984. Too many fishermen? Circe 17~1~:33-36. Garcia, S. 1986. A highly successful seasonal trawling ban: the Cyprus effect. ICLA]?~ Newsletter 9~1~:3-4. Johannes, R. E. 1978. Traditional marine conservation methods in Oceania and their demise. Unreal Review Ecological Sy~tcrru 9:149-164. Johannes, R. E. 1981. Working with fishermen to improve coastal tropical fisheries and resource management. Bulletin of Marinc Scicnec 31~3~:673- 680. Kurien, J. 1986. Netting a decent living. I~terna;tional Agricultural Development 6~3~:10-11. Neal, R. 1982. Dilemma of the small-scale fishermen. ICLAR-M Newsletter 5~3~:77-79. Panayotou, T. 1985. Sma~l-Scalc Fisheries in A - a. Socioeconomic Analy~i~ and Policy. IDRC-229e, International Development Research Centre, Ottawa, Canada. Pauly, D. 1985. Artisanal fishing and environmental conservation in South- east Asian Seas. Wallaceana 41~9~:3-5. Perera, L. C. 1985. Problems of the fishermen in Bangladesh. ADAB News 12~6~:11-23. Phinney, R. 1986. Big boost for infant fishery industry (in Vanuatu). Agricul- tural Information Dcoclopmcnt Bulletin 8~3~:2-3. Platteau, J. P. 1985. Marine fishing and agriculture: a contrasting picture. Appropriate Tcchnology 23~3~:13-15. Poggie, J. J. 1980. Small-scale fishermen's psychocultural characteristics and cooperative formation. An;l;hropological Quarterly 53:20-28. Pollaac, R. B. 1982. Sociocultural aspects of technological and institutional change among small-scale fishermen. Pp. 225-247 in Modernization and Marine Fisheries Policy, J. R. Maiolo and M. K. Orbach feds ~ Ann Abhor Science, Ann Arbor. Michigan IJR A Checking the march of technology. World Fishing ~ _ , _ _ . O , _ _ . Pollnac, R. B. 1985. Social and cultural characteristics in small-~cale fishery development. In Putting Pcopic First, M. M. Cernea (ed.~. Oxford University Press, New York, USA. Posner, G. S., and J. Sutinen. 1984. Overfished Stock, UndernourmAcd Pcopic, and Underbencfited Coastal States of Scat Africa: Opportunitice for Marinc FuAcrics Management and Dcvelopmcnt. U.S. Agency for International Development, Washington, D.C., USA. Smith, I. 1979. A research framework for traditional fisheries. ICLARM Ncu~sleticr 3~3~:3-4. Stevenson, D., R. Pollnac, and P. Logan. 1982. A Guide for the Small-Scale Fishery Adrrunistrator: Information from the Harvc~t Sector. International Center for Marine Resource Development, Kingston, Rhode Island, USA. Thomson, D. 1985. Convict within the fishing industry: large-scale vs. small-scale. Appropriate Tcchnology 12~3~:1-4.

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In developing countries, traditional fishermen are important food contributors, yet technological information and development assistance to third-world nations often focuses on agriculture and industrial fishing, without addressing the needs of independent, small-scale fishermen.

This book explores technological considerations of small-scale, primitive fishing technologies, and describes innovative, relatively inexpensive methods and tools that have already been successfully applied in developing countries. It offers practical information about all aspects of small-scale fishing, including boat design and construction, fishing methods and gear, artificial reef construction and fish aggregating devices, techniques for coastal mariculture, and simple methods for processing and preserving fish once they are caught. Fisheries Technologies for Developing Countries is illustrated throughout with photographs of the devices and construction methods described in the text.

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