Coastal Shrimp Farming in Thailand: Searching for Sustainability

7 Coastal Shrimp Farming in Thailand: Searching for Sustainability B. Szuster Department of Geography, University of Hawai’i at Manoa, Honolulu, Hawaii, USA, e-mail: [email protected] Abstract Shrimp farming in Thailand provides a fascinating example of how the global trade in agricultural com- modities can produce rapid transformations in land use and resource allocation within coastal regions of tropical developing nations. These transformations can have profound implications for the long-term integrity of coastal ecosystems, and represent a significant challenge to government agencies attempting to manage land and water resources. Thailand’s shrimp-farming industry has suffered numerous regional ‘boom and bust’ production cycles that created considerable environmental damage in rural communities. At a national scale, these events were largely masked, however, by a shifting cultivation strategy and local adaptations in husbandry techniques. This chapter outlines the need to upgrade planning systems, improve water supply infrastructure and enhance extension training services within coastal communities to address ongoing systemic environmental management problems within the Thai shrimp-farming industry. Introduction Environmental problems have created widespread crop failures throughout In Lewis Carroll’s Through the Looking Glass, Thailand, but a predicted national-level col- the Red Queen tells Alice that ‘in this place it lapse in farmed shrimp production has not takes all the running you can do to keep in occurred (Dierberg and Kiattisimkul, 1996; the same place’. This phrase has been used to Vandergeest et al., 1999). This chapter traces illustrate a variety of natural and social phe- the development of shrimp farming in nomena (Van Valen, 1973) and it also aptly Thailand. It argues that the Thai aquaculture describes the history of shrimp farming in industry has for many years managed to coastal Thailand. This nation has been a lead- avoid a national-scale collapse in shrimp ing global producer of farmed shrimp since production by shifting farm sites and modi- 1992 (FAO, 2002), but the industry has been fying husbandry techniques. Although these plagued by persistent environmental prob- strategies have succeeded in maintaining lems stemming from a combination of natural overall production levels, underlying prob- resource degradation and associated viral dis- lems related to planning, infrastructure and ease outbreaks (Szuster and Flaherty, 2002). social organization continue to exist and © CAB International 2006. Environment and Livelihoods in Tropical 86 Coastal Zones (eds C.T. Hoanh, T.P. Tuong, J.W. Gowing and B. Hardy) Coastal Shrimp Farming in Thailand 87 threaten the long-term sustainability of poor survival rates. Species cultured in this coastal shrimp farming in Thailand. manner include the banana shrimp (Penaeus merguiensis), Indian white shrimp (P. indicus), school shrimp (Metapeneaus monoceros) and History of Coastal Shrimp Farming in black tiger shrimp (P. monodon). Thailand Simple, traditional shrimp-farming techniques were modified during the late pre- Thailand possesses over 2700 km of coastline expansion phase. New shallow shrimp ponds and a tropical climate ideal for farming were constructed within coastal mud flats and marine species such as shrimp. Basic bio- numerous salt farms were also converted to physical factors are important, but the pres- shrimp production after World War II. This ence of appropriate aquaculture technologies, conversion was largely motivated by low agricultural wages and the availability of depressed salt prices, and more than 50% of government tax incentives were also critical the salt farms in the upper Gulf of Thailand in supporting the development of shrimp region had been converted to shrimp produc- farming in Thailand (Kongkeo, 1995). The tion by the late 1960s (Csavas, 1994). Pond shrimp-farming industry has gone through enclosures are still large in modified tradi- several distinct developmental phases that tional systems (5 ha or more), but yields can are reviewed below to illustrate the ability of reach 400 kg/ha/year by exercising limited Thai aquaculturalists to innovate and control over fry stocking, improving water respond to changing environmental and management and applying manure or chemi- socio-economic conditions. cal fertilizers to induce algal blooms. Only a small number of modified traditional shrimp farms continue to operate in Thailand today Pre-expansion phase (1930–1971) because of the modest harvests associated with this culture system (Pillay, 1997). Shrimp farming was probably introduced to Environmental damage associated with tradi- coastal Thailand by Chinese immigrants dur- tional shrimp farming is generally limited, but ing the 1930s (Tookwinas, 1993). These early a large amount of intratidal land is needed for farms (called thammachaat or ‘natural farms’) pond enclosures and this requirement can applied traditional techniques that involved affect coastal habitats such as mangrove. flooding low-lying coastal paddy fields during the dry season. Wild shrimp within the seawater were captured during this process Early expansion (1972–1987) and retained until the paddy fields were drained prior to planting a wet-season rice Shrimp farming continued in a largely tradi- crop. Enclosures were large (30 ha or more) tional form in Thailand until the early 1970s, and a limited amount of daily water when the Thai Department of Fisheries exchange was provided by natural tidal began experimenting with semi-intensive flows. Traditional farming techniques were monoculture techniques (Katesombun, 1992). inherently a polyculture because seawater This modified culture system provided provided the entire supply of shrimp seed higher yields and was widely adopted in and farmers exerted no control over species coastal areas already supporting traditional composition. Tidal flows also provided natu- shrimp farms. Black tiger shrimp were the rally occurring food organisms to sustain the focus of semi-intensive husbandry experi- captured shrimp during the culture period. ments because this species possesses a high Traditional shrimp farming requires no spe- export value and is able to grow quickly cial technical skills or infrastructure, and under artificial conditions (Pillay, 1990). input costs are minimal due to the use of nat- Another factor was the successful produc- urally occurring seed stock and food. Yields tion of hatchery-raised black tiger shrimp are low (approximately 200 kg/ha/year), postlarvae by Thai personnel trained in due to an absence of stocking control and Japan. This breakthrough, in conjunction 88 B. Szuster with the development of improved feeds Shrimp boom (1988–1995) and husbandry techniques, set the stage for a dramatic expansion of shrimp farming in The introduction of the semi-intensive cul- coastal Thailand (Liao, 1992). ture systems to Thailand was quickly fol- Semi-intensive shrimp culture uses pond lowed by the development of intensive enclosures that are smaller than traditional farming techniques (called phattana or farms (1–8 ha), but this system provides sig- ‘developed farms’). This technology was nificantly higher yields (up to 1000 introduced from Taiwan and features smaller kg/ha/year). This increase in productivity is ponds (0.16–1.0 ha), the use of hatchery- gained through the use of hatchery-raised fry, raised shrimp fry at high stocking densities, supplementary feeding and a limited degree mechanical aeration, prepared feeds, fertiliz- of mechanical water management provided ers, chemicals and antibiotics (Flaherty and by low-lift axial flow pumps to supplement Karnjanakesorn, 1995). Average farm yields the water exchange provided by tidal action increased to as much as 2000 kg/ha/year (Tookwinas and Ruangpan, 1992). Construct- from 1987 to 1999 and total annual farmed ion costs are higher due to the need to con- shrimp production also skyrocketed (Fig. struct levees or dykes, but the pond 7.1). In addition to favourable biophysical enclosures are more uniform, which provides conditions and the availability of Taiwanese additional control over the grow-out environ- intensive farming technology, the Thai ment (Pillay, 1993). The quality of effluent ‘shrimp boom’ was supported by Thai gov- released into the surrounding environment by ernment policies and international develop- semi-intensive operations is usually poorer ment agencies such as the Asian than that of traditional farms, and overall Development Bank (Flaherty and Vander- environmental impacts are more pronounced geest, 1998). These institutions provided due to the increased culture intensity (Miller, significant assistance to the emerging shrimp 1996, unpublished Masters thesis). However, aquaculture sector in areas such as financial coastal habitats such as mangrove can be less support to potential farmers, aquaculture affected by semi-intensive operations if sited research and extension services and infra- in supra-tidal areas that possess soil and structure construction in coastal areas (e.g. drainage characteristics that are better suited roads and canals). to aquaculture (Menasveta, 1997). Intensive culture techniques were first 400,000 Tiger shrimp Banana shrimp White shrimp 350,000 300,000 250,000 200,000 150,000 Annual yield (t) 100,000 50,000 0 2000 2001 2002 2003 1990 1991 1992 1993 1995 1996 1997 1998 1999 1985 1986 1987 1988 1989 1994 1984 Year Fig. 7.1. Farmed shrimp production in Thailand, 1984–2003. Coastal Shrimp Farming in Thailand 89 adopted in coastal

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