The rice-fish aquaculture system and marketing in the Mekong delta ...

The rice-fish aquaculture system and marketing in the Mekong delta, Vietnam

Akiko IKEGUCHI, Lam My LAN, and Duong Nhut LONG

横浜国立大学教育人間科学部紀要Ⅲ（社会科学）№10 別刷

Reprinted from THE SOCIAL SCIENCES Journal of the Faculty of Education and Human Sciences Yokohama National University No.10, FEBRUARY, 2008

The rice-fish aquaculture system and marketing in the Mekong delta, Vietnam ベトナム・メコンデルタにおける稲作-養魚システムと流通 IKEGUCHI Akiko1, Lam My LAN2, and Duong Nhut LONG2

要旨稲やエビのモノカルチャー地域として描かれることが多いメコンデルタでは、近年輸出の多角化がすすみ農業・養殖形態も多様化している。本稿では、近年の養殖形態を明らかにするとともに、条件不利地域の主要形態である稲作-養魚システムの成立条件について、産地流通とのかかわりから予備的考察をおこなった。調査対象としたカントー省におけるこのシステムでは多魚種のポリカルチャーが主体であり、そのなかには用水から供給される天然種苗も含まれていた。地方市場に近接した地域では、販売に多くの小売商が参加することで多魚種の流通が可能であるが、国道から離れた地域では販売魚種が限られる傾向がみられた。前者の地域ではナマズを主体とした輸出型養殖が成長していることから、地域他部門の成長と流通経路の関係を視野に入れた養殖形態の分析が必要であると考えられる。

1. Introduction The Mekong delta, formed at the mouth of the great Mekong River, is the largest delta in the continental part of Southeast Asia. The landform, affected by the river and tides, seasonal fluctuations in the water level due to the monsoon climate, and saline water intrusion over a wide area, forms a complex pattern of habitats for a wide variety of fauna and flora. Its wetland environment, and diversity and productivity of aquatic resources make it an attractive feature of the region. After the 19th century, the construction of canal networks brought about the rapid development of high-yielding paddy fields, making Vietnam the second largest rice exporter in the world. Previous literature on the regional geography of the Mekong delta paid much attention to this characteristic as a rice-production area, and its physical and socioeconomic background have been described by many authors. After the market economy was introduced in 1986 by Doi Moi (renovation), as black tiger shrimp cultivation expanded rapidly, the geography of its cultivation system was described. However, other types of aquaculture systems and uses of aquatic resources had not yet fully been described. Recently, rice or shrimp monoculture has been criticized for the damage it causes to the natural environment, and the multiple use of local resources is encouraged both by scholars and government policy. The regional situation surrounding the commercial production of aquatic resources is also changing rapidly. Such changes in the use of aquatic resources are of

1 2

Faculty of Education and Human Sciences, Yokohama National University Institute of Aquaculture and Fisheries Sciences, College of Agriculture, Can Tho University

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IKEGUCHI Akiko, Lam My LAN, and Duong Nhut LONG

geographical significance, as they dynamically reflect regional differences in the physical and socio-economic environments, and access to markets of various scales. This study reports the results of an exploratory survey on one of these aquaculture systems; the rice-fish cultivation system in the inner part of the Mekong delta. One of the diversified farming systems that flourished after Doi Moi is the combination of rice and other commercial products, which included fish, animal husbandry, fruits, etc (Tanaka 1995). One popular farming system was called the “VAC” system, which stands for “Vuon (fruit & vegetable garden), Ao (pond), Chuong (animal pen)”. This household-scale farming operation mainly produces rice, but also produces several other kinds of produce such as fruit, vegetables, poultry, animals, and fish on the same farm. The system was encouraged by state and local government, and domestic and overseas scholars for a number of reasons. Firstly, it increases the income of household-scale farms with little capital input. Secondly, it reduces the economic risks involved in the rice monoculture system, which is vulnerable to price fluctuations in the international rice market. Thirdly, it was considered to be ecologically desirable, since it utilizes various ecological niches within the farm, thus leading to sustainable land use in comparison with monoculture systems, which often necessitate extensive environmental transformation. The combination of rice and fish cultivation is the mainstay of the VAC system, as it raises income, and is well suited to local wetland conditions. A significant number of studies have been carried out on the sustainability of the rice-fish cultivation system in the Mekong delta. They mostly discuss and evaluate suitable farming techniques, for instance, Long, D.N. at Can Tho University in Vietnam (Long 2002), and other scholars of agro-ecological interest (Berg 2002). Fewer studies have discussed the socio-economic aspects. Among them, Duong et al. (1998) discussed constraints on rice-fish cultivation. With regard to the central part of the delta, they indicated problems such as low fish prices, damage by flooding, and fluctuations in rice prices. Sinh et al. (1997) conducted a comprehensive study on marketing channels, the behavior of farmers and traders in the central part of the Mekong delta. By means of surveys in several districts, they showed that a significant number of retailers participated in farm gate marketing, and the channels remained rather competitive. Yamazaki and Duong (1998) compared productivity across different scales of operation. Focusing on the central part of the delta, they argue that the harvesting of wild resources was important for small scale or landless farmers. With their useful insights in mind, this work shows that the following points may be further discussed from a geographical perspective. Firstly, the kind of geographical conditions that affect the production-marketing relationship within rice-fish cultivation. In particular, a framework is needed to describe the conditions required to sustain multi-species fish cultivation. Secondly, since the previous studies were conducted in the mid 1990’s, recent changes in the market and production should be considered. These discussions need to include plans for comprehensive research, and this paper aims to provide some perspectives for future research. A field survey was carried out from 25th August to 13th September in 2005 in Can Tho province in the central part of the Mekong delta. Department of Fisheries at the provincial and district levels, and local aquaculture extension centers were visited and, where available, fisheries statistics were collected. Two villages situated in the floodplain in Can Tho were chosen for an intensive interview survey. Interviews were carried out in 9 households in one village, and 21 in the other. The questions were structured as follows: A. Household profile: family size; farm area (own/rent) and its structure; labor employment;


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experience in rice-fish cultivation systems B. Combination of crops (crop year of 2004): crop cycle; rice - varieties, production, and selling price; crops/produce other than rice and fish C. Fish production and sales (crop year of 2004): produced species; fingerlings (size, stocking rate, cost); feeding; harvest (size, weight, price); selling activities; buyers’ residence for each fish species The following section shows the recent status of aquaculture in the Mekong delta in Vietnam (Chapter 2). Then, the study will focus on fish cultivation systems in the central part of the delta. After describing the major cultivation systems and their geographical distribution in the region (Chapter 3), the results of intensive survey with farmers of rice-culture systems in two villages will be presented (Chapter 4). Based on these results, the study will discuss the geographical characteristics of the production-marketing relationship, with special reference to multi-species cultivation systems, and propose a research framework subject for understanding the conditions of diversified farming systems.

2. Aquaculture and the physical environment in the Mekong delta, Vietnam Located at the mouth of the great Mekong River, the aquaculture environment in the delta is largely affected by its landform, water level fluctuations, and salinity. The landform and agro-ecological characteristics of the upper part of the delta are determined by the sediment and water brought by the Hau River and the Tien River, two tributaries of the Mekong River (Fig. 1). Narrow natural levees are formed on the banks, and back swamps and extensive floodplains are formed beyond the banks. During the rainy season, from June to October, the floodplain is flooded, creating an extensive habitat for various freshwater fish and other aquatic creatures. However, high-yield rice cultivation was restricted in this area until the network of water drainage canals was built during the period of French colonization. Even now, the inner floodplain is considered to be the most difficult area for modern types of agriculture. On the coast facing the South China Sea, coastal flats with sand dunes and beach ridges are formed by the tide and waves. The sandy soil is well drained, and orchards and vegetable gardens are predominant, especially near Ho Chi Minh (HCM) city. In combination with mangrove areas, the coastal area is largely developed for shrimp cultivation. Although the use of aquatic resources has been a common aspect of daily life on the delta, commercial aquaculture rapidly developed after the economic recovery in 1986. In the 1990’s, the rapid expansion of shrimp farming received much attention from overseas but, in recent years, various types of aquaculture system have developed for both the domestic and oversea markets. Table 1 shows the distribution of major aquaculture systems by province. Although the statistics are intended to show different cultivation systems by province, making simple comparison rather difficult, they may at least serve as a rough overview of the current status of aquaculture in the delta. In Bac Lieu and Ca Mau, especially in the coastal areas, brackish water prawns, mainly black tiger prawns (Penaeus monodon), developed extensively. In the coastal areas nearer to HCM city, various types of cultivation systems are in operation, and are listed in the statistics. In Ben Tre and Tien Giang, the cultivation of mollusks such as clams (Meretrix lyrata) and blood cockles (Tegillarca granosa) are becoming economically significant, and freshwater prawns are cultivated in Ben Tre and Vinh Long. Freshwater fish are cultivated in most of the provinces, especially in Can Tho, Hau Giang, and Soc Trang province. Many species are included in this category, but a recent trend is the growth of export-oriented

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catfish cultivation in the upper part of delta. Initially in An Giang and Dong Thap province, the cultivation of Mekong catfish Pangasius spp. was started in the late 1990’s. In 2003, the annual exporting of Pangasius to EU and U.S.A. grew to 2,240 million US dollars, and became the second largest aquaculture business after prawn cultivation. Their cultivation involves the use of floating cages in rivers, or ponds built along the river, but not in areas remote from the rivers, where oxygen supplied by the flow of water is insufficient. Overall, the coastal areas of the delta are characterized as prawn cultivation areas, with more variety in areas nearer the city, while the upper part of the Hau and Tien rivers are becoming Pangasius cultivation areas. The central part of the delta, such as in Can Tho province, is located between these growing regions. Some areas have introduced export-oriented Pangasius cultivation, but the areas on the floodplain still depend on other freshwater fish for the domestic market. The following section describes the cultivation systems in Can Tho province, and their distribution within the province.

3. Aquaculture in the central floodplain: Can Tho province Can Tho provice is situated on the right bank of Hau river between An Giang province in the north, and Hau Giang province in the south (Fig.2). Adjacent to the narrow natural levees formed along the Hau River, a back swamp has been formed toward the southwest. Thot Not district, and four city quarters (Quan O Mon, Q. Binh Thuy, Q. Ninh Kieu, Q. Cai Rang), are situated on the natural levees and in the back swamp. In the western part of the province, Vinh Thanh, Co Do, and Phong Dien districts are located on the floodplain, which extends toward the broad depression. Initial settlements were said to have been developed on the natural levees by Khmer people in the early 19th century. During the period of French colonization, large canals were excavated for water transport and land reclamation (Kono 2001). This canal development attracted Kinh settlers and paddy areas expanded. After independence, the government continued the construction of canal networks on the western part of the floodplain, which are now the main means of transport, and also provide a habitat for live freshwater resources. Quan Ninh Kieu, the downtown area of Can Tho, was designated by the French colonial government as the pickup point for rice from the western part of the delta, which was rigorously developed for rice exportation. Until the present time, Q. Ninh Kieu has grown as the trading, administration, and academic center of the delta, and the population density in 2003 was 71 persons per hectare. New industrial areas were developed in Q. Binh Thuy and Q. Cai Rang, and the non-agricultural population is growing in these areas. The three districts of Thot Not, Vinh Thanh, and Co Do, and the two suburb quarters of O Mon and Phong Dien, are primarily agricultural regions, where the percentage of farmers in the population were 26%, 59%, 44%, 40%, 49%, respectively in 2003. In general, aquaculture is operated by these farmers, who also cultivate rice. The major aquaculture systems in these regions are pond cultivation, rice-fish cultivation, rice-prawn cultivation, and cage cultivation. Farmers involved in pond cultivation dig 1-3m depth ponds along the canal, and produce high-priced species such as Pangasius spp., Anabas testudineus, and sometimes non-fish resources, such as soft-shelled turtles Pelodiscus sp.. This cultivation is carried out intensively, using industrially produced pellets and frequent changes of water to ensure a good supply of oxygen. Rice-fish cultivation and rice-prawn cultivation are combinations of paddy-aquaculture, which use paddies and irrigation channels on farms. Cage cultivation is mainly intended for export-oriented Pangasius cultivation. Floating cages are set up in rivers and canals, allowing


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a maximum supply of oxygen, and high density fish stocking. Table 2 shows the distribution of these systems by district in Can Tho province. Cage cultivation is common in Thot Not and Q. O Mon, the districts situated along the Hau River. Pond cultivation is largely operated in Co Do, Thot Not, and Vinh Thanh, while rice-fish cultivation and rice-prawn cultivation are restricted mostly to the floodplain areas on the western part of the province. The growth of export-oriented aquaculture is remarkable, especially in riverside areas such as Thot Not. As shown in Table 3, the area of pond cultivation operation has increased since 2001 and, moreover, production has increased rapidly both in pond cultivation and cage cultivation, indicating a shift of production systems to intensive cultivation. Another trend is the increase in rice-fish cultivation since 2003. According to a fisheries extension officer, the farmers who had previously operated rice-monoculture introduced fish cultivation into their paddies following advice from the local Fisheries Department. In order to examine these phenomena from a geographical perspective, the distribution of fish cultivation systems is presented at the village (Xa) level for three agricultural districts (Fig. 3). The introduction of pond cultivation is predominant in the riverside areas of Thot Not, and the areas along road no.80 in Vinh Thanh. In Co Do district, especially in the western part, the rice-fish cultivation system was the mainstay of aquaculture operations. The western part of Co Do area is located in a floodplain, so there is not a sufficient supply of fresh water for pond cultivation. Compared to Vinh Thanh, a lack of major roads for fish transportation may be considered a hindrance to the introduction of high-yield types of aquaculture. It can be said that the rice-fish cultivation system, although in decline in its role in the riverside or roadside regions, has remained an important measure for disadvantaged areas in terms of supplies of fresh water and infrastructure. The following section describes the operation of the rice-fish cultivation at the household level in two villages; Dong Hiep in Vinh Thanh, and Thanh An in Vinh Thanh (Fig. 3). In particular, the section will focus on how the culturing of multiple fish species in a household is made possible by a combination of different types of resource use and marketing schemes.

4. Rice-fish cultivation and marketing 1) Rice-fish cultivation in the floodplain area: Dong Hiep Dong Hiep village is located on the floodplain in Co Do district, with a total area of 3024ha, 2570ha (85%) of which is rice paddy. The village is made up of 11 hamlets (Ap). In this study, Dong Thang hamlet was selected for an interview survey. The area of Dong Thang hamlet is 275ha, and there were 167 households (population 865) in 2005. Of these, 118 households are engaged in rice-fish cultivation, 2 households in rice-prawn cultivation and 47 households in rice mono-culture. Twenty-one households operating rice-fish cultivation were interviewed in this study. Table 4 shows the profile of the interviewed households. Ages in the households ranged from 32 to 64, and their experience in rice-fish cultivation was less than 10 years. The area of farmland ranged from 0.7 to 6.0 hectares, and the land was owned by the householders themselves, except for one household. Half of them (10 households) cultivated three crops of rice annually; November-February (winter rice), February-May (spring rice), and May-August (summer rice) in 2004. Winter rice and spring rice can yield about 7t / ha, while the summer rice yield is as low as 5t / ha. The remaining households cultivate only winter and spring rice. A farm typically has an irrigation channel surrounding the paddy. The depth of the channel is about 1.5 to 2 meters, and the depth of the paddy is 0.25 to 1.0m. In the case of household ID 1, who cultivated three crops of rice, common carp fingerlings were released into

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the channel after harvesting the winter rice. The size of the fingerlings was 150-200 fish/ kg, and 4 kg were released for 6ha of paddy. After preparation of the spring rice was completed, the water level was increased to fill the paddy, and the fingerlings entered the paddy, feeding on naturally occurring foods. This continued until the following November, with fish being released either into the paddy or the channel. Before beginning winter rice preparation, 150kg of common carp were harvested. Their size was 5 to 6 fish/kg, and they were priced at 6,000VND /kg. Additionally, a total of 20kg of climbing perch, snakehead, and silver barb was also harvested. This harvest was from fingerlings naturally introduced from canal water. Table 5 shows the combination of income sources for each household. The major source of income was rice, which comprised 51 to 96 % of total income. In addition to fish cultivation, other types of farming such as pig farming, orchards, vegetables, and poultry were also combined with rice cultivation. Among these activities, fish cultivation usually costs less than pigs and poultry, and thus is considered reliable as a secondary source of income. Although some farmers attempted feeding with purchased pellets, the most common fish food was naturally occurring food found in the paddy, or rice bran produced from the paddy. As with household ID 1, every household harvested several different fish species, which often included those grown from naturally occurring fingerlings (Table 6). The most commonly reared species was common carp, and all of the households purchased fingerlings from breeders. Silver barb, silver carp, and tilapia are often reared from artificially produced fingerling. On the other hand, climbing perch and snakehead were reared from wild fingerling in all cases. Especially, income from snakehead was second or third in importance. The selling price of snakehead in 2004 ranged from 12,000VND/kg for the size of 10 fish/kg, to 18,000 VND/kg for the size of 3 fish/kg. Compared to common carp (which was 9,000-13,000 VND/kg), silver barb (6,000-8,000 VND/kg), or silver carp (3,000-6,000VND/kg), the price of snakehead was remarkable, although the harvests were always small due to the carnivorous nature of the fish. According to some farmers, there used to be more species harvested from naturally introduced fingerlings. Freshwater shrimps, crabs, and other fish species were harvested. Rearing multiple species within the paddy is advantageous, since the animals occupy different niches, thus allowing the effective utilization of small farms. Also, the utilization of original ecological niches on the farm motivates farmers to sustain the biodiversity of the farm. However, the farmers believe that those resources fell into decline following the application of pesticides to eliminate golden apple snails (Pomacea canaliculata). This snail, well known as a pest which is harmful to rice in Asian countries, spread over the Mekong delta in 1990’s (Mochida 1991). 2) Marketing behavior of farmers and traders One of the key factors in sustaining the cultivation of multiple species in the rice-fish system is the successful commercialization of the various species which are harvested in small quantities. This section examines how the different species of fish are marketed and the geographical background, by comparing case studies in two villages; Dong Hiep in Co Do, and Thanh Quoi in Vinh Thanh. Thanh Quoi is located at the side of road no.80, which joins road no. 91, connecting Can Tho and An Giang. As shown in Figure 3, the farmers have introduced pond cultivation in this area, despite its location on the floodplain, as is the case in Co Do. Although canals are still an important means of transportation in the delta area, road-side locations are becoming advantageous for commercial agriculture. Table 7 shows the marketing of 5 fish species in Dong Hiep village. This table indicates


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where the traders came from to purchase fish at the farm gate. In Dong Hiep, traders were most commonly from Thi Tran O Mon and Thoi Lai, the central towns in O Mon and Co Do respectively. They were all dealers who send the fish, either to other dealers, or to shops in the cities. Traders from TT O Mon tend to purchase common carp, whilst other fish species, which are found in smaller quantities than common carp, were purchased by traders from smaller towns. According to one dealer who purchased snakehead, she visited hamlets in Co Do district to purchase snakehead exclusively. She traded regularly with wholesalers in the market and shops in HCM city. When she received orders, she would arrange a truck and send the fish to them. The selling of fish in downtown Can Tho was rare. The marketing of 11 fish species in Thanh Quoi and Thanh An is presented in Table 8. Although fewer households (9 households) were interviewed than in Dong Hiep, it was found that a greater variety of fish were being sold by farmers in these two villages. The most common marketing methods were wholesale or retail in local markets in Thanh Quoi or Thanh An carried out by wives or daughters from the household. Dealers from O Mon purchased silver barb and climbing perch, while 10 species of species fish were being marketed at the local market. In Vinh Thanh, there were also several dealers who collected small amounts of fish such as Gourami and Catfish. This suggests the importance of access to markets selling local resources, although due consideration should be given to their selling capacity.

5. Discussion and Conclusion This paper has presented the status of rice-fish cultivation systems among diversified aquaculture systems in the Mekong delta. An intensive interview survey was carried out at villages in the floodplain area of Can Tho province. The findings can be summarized as follows: - In the coastal areas, prawn cultivation is still dominant, but other types of commercial aquaculture such as crab and mollusk cultivation were listed as important activities especially in those areas close to HCM city. - In the inner part of the delta, freshwater fish cultivation is dominant. Of the various cultivation systems, pond cultivation and cage cultivation - which mainly involve the rearing of Mekong catfish (Pangasius spp.) - flourished along the Hau river and major roads after 2000. - The rice-fish cultivation system remained the major cultivation system in the area of the floodplain located far from the river and main roads. - In the floodplain area remote from the main roads, 50-96% of household income was dependant on rice, and fish was the second most important source of income. Five species of fish were reported as being harvested from the farms, of which 2-3 species were from artificially reared fingerlings. The buyers were mostly dealers from large towns along the riverside, who bring fish to HCM city or other provinces. - Although the size of the sample was relatively small, a comparative survey in a village near the main road showed that 11 species of fish were utilized for generating income. The marketing of these fish was mostly carried out by householders themselves, using local retail markets. In previous literature, the rice-fish cultivation system has been considered ideal as a means of sustainable agriculture, especially when it involves the utilization of various live resources inhabiting the farm. An important research agenda in avoiding mono-culture - which tends to result in the decline of wild life due to the use of chemicals or drastic landform changes - is the means by which the multiple uses of local resources are sustained. From an economic and geographical perspective, the marketing channels for different fish, together with

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the related geographical conditions should be examined. Among the previous studies on the marketing of fish from the rice-fish cultivation system, Le Xuan Sinh et al. (1997) showed that retailers played an important role in farm gate trading. However, the present survey in Dong Hiep village in Co Do suggests that this should be understood in terms of geographical conditions. The survey in Can Tho province was conducted in O Mon district, which is located in a suburb of downtown Can Tho. The traders of O Mon may have easier access to the largest local market and, thus, various fish may be marketed in small amounts by retailers. The dealers in large towns like O Mon should have the advantage of being able to accumulate capital to extend their market network between other districts and HCM city. The author has also described in a study on suburban Hanoi the case of the growth of the transaction relationship from the scale of retailer to dealer or wholesaler (Ikeguchi 2007). An exploratory survey in Vinh Thanh implied the potential of local markets near the main roads to support the diversified marketing of small quantities of different fish. In order to understand geographical conditions related to multi-species rice-fish cultivation, further research is needed to compare the production-marketing relationship in villages in different locations and physical conditions. Also, if villages like Thanh Quoi and Thanh An have potential for a sustainable rice-fish cultivation, what kind of regional factors support the purchasing power of the local markets, which are quite remote from the central town of Can Tho? One possible factor is the growth of commercial agro-industries along the Hau River and, in particular Mekong catfish cultivation. This should be another geographical question for future studies. Acknowledgements The authors would like to express their gratitude to Mr. Hua Thai NHAN and other staff of Institute of Aquaculture and Fisheries Sciences, College of Agriculture, Can Tho University, for their assistance with the field survey. This research was funded by Grant-in-Aid for Scientific Research (17720219) of Japan Society for the Promotion of Science (JSPS). Literature Berg, H. 2002. Rice monoculture and integrated rice-fish farming in the Mekong delta, Vietnam - economic and ecological considerations. Ecological Economics 41(1):95-107. Berg, H. 2002. Pesticide use in rice and rice-fish farms in the Mekong delta, Vietnam. Crop Protection 20(10):897-905. D. N. Long 2002 Sustainable development of integrated rice-fish poly-culture systems in the Mekong delta of Vietnam. Ph.D thesis submitted to Faculty of Science, University of Namur, Belgium. Ikeguchi, A. 2007 Development of transaction relations in freshwater fish wholesale markets in Hanoi, Vietnam. Geographical Review of Japan 80(5): 1-28. L.X. Sinh,, N.A.Tuan, Pomeroy, R.S., Genio, E., Garces, A., and Agbayani, R.F. 1997. Marketing of freshwater table fish in the central area of the Mekong river delta. West-east-south programme, institutional upgrading for sustainable aquaculture development in the Mekong


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delta of Vietnam. Kono, Y. 2001 Canal development and intensification of rice cultivation in the Mekong delta: a case study in Can Tho province, Vietnam. Southeast Asian Studies 39(1): 70-85. L.T. Duong, D.K. Nhan, Rothuis, A., P.M. Quang, T.Q. Giau, H.H. Chi, L.T. Thuy, N.V. Hoa, and L.X. Sinh 1998 Integrated rice-fish culture in the Mekong delta of Vietnam: problems, constraints and opportunities for sustainable agriculture. In Vo Tong Xuan and Shigeo Matsui eds. Development of farming systems in the Mekong delta of Vietnam. Ho Chi Minh city publishing house. Mochida,0. 1991. Spread of freshwater Pomacea snails(Pilidae, Mollusea ) from Argentina to Asia. Micronesiea Suppl 3:51-62. N.H. Chiem 1993. Geo-pedological study of the Mekong delta. Southeast Asian Studies 31(2): 158-186. Tanaka, K. 1995. Transformation of rice-based cropping patterns in the Mekong delta: from intensification to diversification. Southeast Asian Studies 33(3):81-96. Yamazaki, R. and D.N. Thanh 1998. Agricultural structure of the Mekong Delta: a case study of the Thot Not district, Can Tho province. Vo Tong Xuan and Matsui, Shigeo eds., Development of farming systems in the Mekong Delta of Vietnam. Ho Chi Minh city publishing house. 117-145.

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Figure 1 Geomorphological map of the Mekong delta (Simplified after Nguyen 1993)


Figure 2 Population density by district in Can Tho, Vietnam (2003) (Data from UBND Can Tho 2003)

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Figure 3 Proportion of fish culture systems by village in three agricultural districts in Can Tho (2004) (Data from unpublished reports of the dictrict offices of Thot Not, Vinh Thanh, and Co Do)

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Table 1 Aquaculture area by province in the Mekong delta, Vietnam (2004) Freshwater(ha)

Province Long An Tien Giang Ben Tre Vinh Long Tra Vinh Dong Thap An Giang Can Tho Hau Giang Kien Giang Soc Trang Bac Lieu Ca Mau

Brackish water(ha)

Prawn (MacrobraOthers chium rosenbergii)

Fish 3,000 5,422 3,239 9,572 na na 1,122 12,327 9,038 7,544 10,363 na na

422 38 2,002 550 na na 126 291 40 na 22 na na

na 12 141 9 640 na na na na na 656 2,239 na

Prawn (Penaeus spp.)

Crab (Scylla spp.)

5,700 3,919 32,719 0 23,402 na 0 0 69 74,771 43,311 116,473 248,000

Molluscs

Others

25 na na na 2,150 649 40 4,021 na 0 0 0 3,618 na na na na na 0 0 0 0 0 0 0 0 0 230 7,250 8,355 na na na na na na (Crab&Molluscs 32,000)

na: data not available (Department of fisheries, Vietnam, 2004)

Table 2 Aquaculture area by district in Can Tho province (2004) Pond culture (Ha) Q. Ninh Kieu

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Rice-fish culture (Ha)

Rice-prawn culture (Ha)

Cage culture number

(Pangasius culture) (Ha)

Total aquaculture (Ha)

0

1.5

0

(8)

20.5 109.9

Q. Binh Thuy

97.2

12.5

0.2

26

(12)

Q. Cai Rang

191.5

0.5

0.5

27

na

192.5

Q. O Mon

197

52.1

9.5

72

(125.5)

258.6

H. Phong Dien

208

6.3

1.5

0

na

215.8 8738.1

H. Co Do

529.4

8139.15

69.55

5

(30.4)

H. Thot Not

432.58

40.0

10.6

135

(341.7)

483.18

H. Vinh Thanh

445.96

184.1

229.1

37

(156)

859.16

(Data from unpublished report of Department of fisheries, Can Tho, 2004)

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Table 3 The change of aquaculture systems in Thot Not district, Can Tho (1996-2004) Rice-fish culture

Pond culture

Rice-prawn culture

area(ha)

production(t)

area(ha)

production(t)

area(ha)

production(t)

36.7 7.8 10.5 15.5 10.5 14.6 10.1 28.2 42.5

17.0 2.0 3.7 5.3 4.5 na 1.3 15.5 409.3

125.4 93.3 94.5 115.2 170.3 176.4 332.2 255.5 361.1

958 520 660 2120 3295 na 18725 7499 48779

2.0 0.0 0.0 5.0 0.0 42.5 14.5 15.0 7.1

0.5 0 0 1.3 0 na 9.3 7.5 5.5

1996 1997 1998 1999 2000 2001 2002 2003 2004

Cage culture number of cage

production(t)

72 73 82 96 100 92 78 85 212

399 336.6 372 374.1 409.7 845 1325 1110 1548.4

na: data not available (Data from Department of agriculture and fisheries, Thot Not district)

Table 4 Profile of the interviewed households in Dong Hiep, Co Do, Can Tho Age of household head

Number of children*1

ID 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

64 49 57 48 41 53 49 53 42 56 38 34 32 55 51 60 53 49 na 45 48

2F3M 1F1M 3F4M 2F3M 3F1M 3F5M 2F1M 2F4M 1F1M 2F2M 2F1M 2M 1M 4F2M 2F5M 2F6M 3F3M 3F1M 3F4M 2F3M 2F1M

na: data not available *1 F: female, M: Male

Experience in rice-fish

Farmland area

Farmland ownership

year

ha

ha

10 10 5 7 4 4 10 7 9 2 8 4 4 5 na 6 5 5 5 5 4

6.0 5.0 5.0 4.6 4.5 4.5 4.0 3.4 3.2 3.2 3.0 3.0 3.0 2.8 2.7 2.6 2.5 2.1 2.0 1.5 0.7

6.0 5.0 5.0 2.2 4.5 4.5 4.0 3.4 3.2 3.2 3.0 3.0 3.0 2.8 2.7 2.6 2.5 2.1 2.0 1.5 0.7

Crop cycle

2rice1fish 3rice1fish 3rice1fish 3rice1fish 2rice1fish 3rice1fish 2rice1fish 2rice1fish 2rice2fish 2rice2fish 2rice2fish 3rice1fish 2rice1fish 2rice1fish 3rice1fish 2rice2fish 3rice1fish 2rice1fish 3rice1fish 3rice1fish 3rice1fish

3.0

2.8

2.7

2.6

2.5

2.1

2.0

1.5

0.7

14

15

16

17

18

19

20

21

19.2

47.0

62.6

62.2

75.0

28.2

84.6

67.6

67.1

101.2

47.3

77.2

6.3

78.0

97.5

135.1

96.8

142.6

136.2

150.1

146.3

Rice* 106VND

96.1

81.4

83.6

92.4

83.2

87.1

87.4

53.8

90.3

83.7

48.6

97.4

51.0

90.1

72.3

80.8

73.2

93.6

95.1

77.4

95.8

%

0.8

4.8

6.3

4.1

11.2

4.2

4.1

20.1

7.3

9.8

25.1

2.1

2.1

8.6

22.4

20.6

5.5

6.8

na

41.9

6.4

Fish*2 106VND

3.9

8.2

8.4

6.2

12.4

12.9

4.3

16.0

9.7

8.1

25.8

2.6

16.7

9.9

16.6

12.3

4.2

4.5

na

21.6

4.2

%

Vegetable

Pig (6million/year)

Pig, vegetable, fruit (total 6million/year)

Pig (1million/year)

Vegetable and flower (4million/year)

None

Pig （no profit this year), rice mill (8million/year)

Pig (20million/year), mango (18million/year)

Duck eggs (39,000eggs/year)

Banana (7-10million/year)

Pig (25million/year)

Vegetable

Mango and vegetable (3-4million/year)

None

Mango (10-15million/year)

Hybrid corn (2.5million/year), pig (9million/year)

Pig (30million/year)

Vegetable (2-3million/year)

Pig (7million/year)

Duck(1-2million/year)

None

VND

Other income source

Table 5 Income source of farm households in Dong Hiep, Co Do, Can Tho (2004)

(Data source: interview survey by the author)

na: data not available *1 Calculated by: production per ha*farm area*rice market price for each crop *2 Calculated by: harvest*purchased price-cost for fingerling-cost for feeding for each species

3.0

13

3.2

9

12

3.4

8

3.2

4.0

7

3.0

4.5

6

11

4.5

5

10

5.0

2

4.6

5.0

1

4

6.0

ID

3

Farm area ha

1

% 0.0 1.0 na 2.0 22.7 6.9 11.1 0.0 32.3 0.0 25.7 8.3 0.0 30.2 8.3 0.0 4.4 1.5 8.0 10.4 0.0

Total income VND 152.7 194.0 143.2 152.3 132.4 167.2 134.9 86.6 12.4 79.3 97.4 121.0 74.4 125.6 96.7 32.3 90.2 67.3 74.9 57.8 20.0


25

26


Table 6 Composition of fish harvest by species in Dong Hiep, Co Do, Can Tho (2004) Common carp ID

6

6

10 VND

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Silver barb 10 VND

5.9 37.8 na 6.4 3.9 14.1 15.9 13.9 SC -0.9 19.4 8.6 4.8 9.8 4.1 3.3 7.1 3.8 6.3 2.8 0.8

Silver carp 6

Tilapia 6

10 VND

Climbing perch 6

Snakehead 106VND

10 VND 10 VND

Total

106VND 0.5

2.8

6.4 41.9 na 7.6 5.5 20.6 22.4 17.5 5.6 2.1 25.1 11.1 7.3 21.4 4.1 4.2 11.2 4.1 6.3 4.8 0.8

1.3

0.3 4.4 3.1 3.6 1.5

0.3 1.2

1.2 0.9 0.9 2.4

0.2 1.0 1.8 SC 1.4

1.8 1.3

2.3 3.0 2.5 0.4 2.5 1.4

0.8 0.0 8.9

1.3 0.2

0.8 0.1

0.8 0.2

0.7 2.5 0.0

2.0

0.0

na: data not available SC: self-consumption (Data source: interview survey by the author)

Table 7 Resident area of the traders purchased fish from Dong Hiep, Co Do, Can Tho (2004) (number of purchase) District Village (xa)

TTOmon

O Mon Thoi Long Other

Type of buyer

Middleman

Middleman

Middleman

8 3 1 1 1 14

1 1 0 2 2 6

1 2 0 0 0 3

Common carp Silver barb Silver carp Climbing perch Snakehead Total

total 10 6 1 3 3 23

Thoi Lai

Co Do Dong Thuan Dong Hiep

Middleman

Middleman

8 0 3 3 2 16

total

Middleman

2 1 0 0 1 4

4 2 2 0 2 10


Table 8 Resident area of the buyers for the fish from Thanh Quoi, Vinh Thanh, Can Tho (2004)

14 3 5 3 5 30

27


District

O Mon

Village (xa)

TT. O Mon Thanh My

Type of buyer

Trader

Common carp Silver barb Silver carp Chronosoma Freshwater crab Snakehead Climbing perch Tilapia Gourami Freshwater shrimp Catfish Total

Total

Vinh Thanh Trader 2 1

1 2 1

3

4


Thanh Quoi Thanh An Vinh Trinh Retail market Middleman Retail market Trader 2 1 1 1 1 1 1 1 1 2 1 2 1 2 2 2 2 1 4 1 17

1 5

1 9

1

5 2 3 1 1 6 3 5 3 4 3 36