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Recent initiatives on the availability and use of aquatic organisms in rice-based farming - M. Halwart

Technical Officer, FAO, Rome, Italy[41]


At the Nineteenth Session of the International Rice Commission (IRC), held in Cairo from 7 to 9 September 1998, member countries were informed about the trends and prospects of fish in rice-based farming systems (Halwart, 1999). The Commission for the IRC member countries, the regional and international institutions and FAO made two recommendations with regard to “fish in rice farming”:

In the same year, FAO and the Secretariat of the Convention on Biological Diversity organized an international Technical Workshop on “Sustaining agricultural biodiversity and agro-ecosystem functions - opportunities, incentives and approaches for the conservation and sustainable use of agricultural biodiversity in agro-ecosystems and production systems” at FAO Headquarters, Rome from 2 to 4 December 1998. A case study pointed out that rice farmers who intensify rice production by using Integrated Pest Management (IPM) also receive enhanced benefits from the diverse aquatic component of the ricefield ecosystem. The workshop concluded that four areas of intervention for the conservation and sustainable use of all agricultural biodiversity, especially at agro-ecosystem level, should be prioritized:

Three workshop recommendations were made:

It was stressed that all organizations in the field of sustainable development need to work further to integrate and mainstream agricultural biodiversity in their policies, programmes and activities in order to develop plans of action on the conservation and sustainable utilization of agricultural biodiversity, especially at agro-ecosystem level. Awareness-raising of all stakeholders about the importance and value of agricultural biodiversity was identified as a priority issue (Aarnink et al., 1999).

Aquatic resources from rice fields and other aquatic environments often constitute a large share of the animal protein intake of poor households, particularly in Southeast Asia. Unfortunately, although this dietary contribution is self-evident for those working in the field, the role of aquatic resources in the food security of rural households is poorly documented because of the complexity of seasonally and spatially variable resources, environments and stakeholder activities. However, evidence is required by policy-makers so that they may formulate more pro-poor policies or make resource-allocation decisions. Greater emphasis on advocacy is therefore required to raise awareness of the role of aquatic resources in food security and poverty alleviation of the rural poor.

With the above conclusions and recommendations as a basis, and timely additional financial support to regular programme resources received by the Government of the Netherlands through the FAO Inter Departmental Working Group on Biodiversity, the Inland Water Resources and Aquaculture Service of the FAO Fisheries Department initiated a regional activity on the availability and use of aquatic organisms in rice-based farming in Asia.


Rice-fish farming systems can be broadly classified as “capture” or “culture” systems, depending on the origin of the fish stock. In the capture system, wild fish enter the rice fields from adjacent water bodies and grow and reproduce in the flooded fields. In the culture system, on the other hand, rice fields are deliberately stocked with fish either simultaneously or alternately with the rice crop. The rice fields may be used for the production of fingerlings or table fish, depending on: the size of fish seed available for stocking; the duration of the fish culture period; and the market needs for fingerlings or table fish (Halwart, 1999). There are also intermediate systems where it is part of the management system that many of the stocked fish fall prey to wild species, as in Thailand. These losses are accepted due to the high market value of the wild fish on local markets (Setboonsarng, 1994).

Many countries in Asia may be termed “rice-fish societies”, in the sense that rice is the staple crop for basic subsistence, while fish is the main source of animal protein (Demaine and Halwart, 2001).

Asian countries as rice-fish societies

The availability of rice and fish has long been associated with prosperity and food security. In Thailand, for example, the early inscription of the thirteenth century king, Ramkhamhaeng, states “in the waters are fish and in the field is rice” as an indicator of wealth and stability. In Viet Nam, there is a saying that “rice and fish are like mother and daughter”.

The cultivation of most rice crops in irrigated, rainfed and deep-water systems offers a suitable environment for fish and other aquatic organisms. Much of the fish for household consumption was traditionally caught from the paddy fields. With the conversion of wetlands into agricultural land and the intensification of rice production, fishery has declined and farmers have turned to aquaculture as an alternative source of animal protein. However, such pressures have not been uniform and there are considerable areas of floodplain in the region where fishery continues to provide an adequate living for the local population.

The nature of fishery varies, depending on the season and the proximity to the river systems. In Cambodia, in the wet season, the main fishery is in the rice field itself. Rice field fishery in this season is largely open access - a sign of the relative abundance of the fish. This is also the case in the cool season when the fish migrate back to the refuges. In the early part of the hot season, some farmers catch fish in deep trap ponds, some of which were originally dug for fish culture under well-intentioned projects; some of the larger trap ponds secure as much as 300 kg of high-value “black fish”, such as snakehead Channa striata (25-40% of the catch) or Clarias catfish (35-40%). These air-breathing species are well adapted to the swamp-like conditions of rice fields with fluctuating water levels and are highly appreciated wild fish in the capture system. They are carnivorous and will feed on other introduced fish but can be sold for twice the price of the equivalent cultured fish on local markets in Thailand. The high prices fetched in Cambodia lead Gregory and Guttman (1996) to claim that farmers in the areas are poor in all but fish. In such contexts, fish culture is unnecessary; it should be noted, however, that there are marked variations in fishery productivity over short distances.


Several studies on the availability and use of aquatic organisms in capture and culture rice-fish systems were begun in the 2000-01 biennium.

The high availability of wild fish usually favoured the development of the capture system in the floodplains of large river systems. Case studies on the capture rice-fish system were therefore initiated in the Upper and Lower Mekong River floodplains: one in Xishuangbanna, Yunnan Province, China, and the other in Kampong Thom Province, Cambodia.

The relatively lower availability of wild fish in remote mountainous areas resulted in the emergence and evolution of the culture rice-fish system. Indigenous rice-fish systems using locally adapted strains of fish species are found in the uplands of northern Viet Nam and the Lao People’s Democratic Republic. Case studies with a focus on the traditional knowledge in these rice-fish societies have been initiated in the Vietnamese Provinces of Hoa Binh, Son La and Lai Chau, and the Laotian Provinces of Xieng Khouang and Houa Phanh.

The objectives of the studies are to collect and document information on the availability of living aquatic resources and the use pattern of rice farmers. Specific attention is being paid to apply participatory methods and techniques to learn about the traditional knowledge of farmers in a particular area.

Study reports are expected to follow a similar pattern. Aquatic species are collected by the farmers themselves using their own tools and techniques. Also, farmers identify the species in their local language and the names are recorded. Smaller species are preserved and bigger species are photographed for reference purposes. All species are listed in databases providing local and scientific names, information on the sampling, special observations for collection and use, and, as far as possible, information on consumption.

At the time of preparation of this paper (January 2002), the case studies from China and Cambodia were just completed; the case studies in the Lao People’s Democratic Republic and Viet Nam began in December 2001 and January 2002, respectively.

An initial analysis of the findings shows that the rice field ecosystems in the study areas have a rich aquatic biodiversity which is extensively used by the local people. The most important group in terms of species diversity and importance for the local people are the fishes. A total of 60 and 70 different fish species were found in the Cambodia and the China study, most of which are consumed fresh or fermented into fish paste. Fewer species are fermented either as fillet or in smaller pieces, dried, salted, smoked, or used for preparing fish sauce. Fish, fresh or processed, is the primary source of protein and usually part of every meal.

As far as home consumption and selling of fish is concerned, it is estimated in the Cambodian case study that an average family of five persons would consume about 1 kg of fresh fish every day during the fishing season. The same family would need about 20 kg of fermented fish paste for the dry season. Everything caught above this would be sold in the market. Depending on the fishing tool employed, a farmer can catch 15 to 20 kg of fish on a good day, although the average fish catch during the fishing season is less than 10 kg per day. The Chinese study also stressed the importance of fish and other aquatic organisms from rice-based systems as part of the daily diet, in particular for the rice-farming Dai minority in Xishuangbanna. The consumption level of aquatic organisms has probably remained constant, but it is estimated that nowadays one-fifth to one-third of consumption is derived from capture in rice-based farming, while one decade ago capture supplied half of the dietary fish requirement.

In addition, several species of crustaceans, molluscs, amphibians, insects, reptiles and aquatic plants were encountered, all of which are used directly, processed for human consumption, as animal feed or bait, or have medicinal value.

An example from the Cambodian study is provided in the Appendix; it illustrates the approach and gives the preliminary findings.


There are indications that the availability of these aquatic resources is declining. Farmers in Xishuangbanna claim that fish are becoming less abundant and that the quantity of aquatic organisms collected in one day is the equivalent of what was collected in just one hour a decade ago. Similarly, the Cambodian study indicates that fish catches have greatly decreased over the past two decades. While the growing human population and the consequent increased fishing pressure on aquatic resources play an important role, management strategies are thought to bear the main part of the blame: pesticide use, destruction of fish breeding grounds and illegal fishing practices, such as electrofishing or chemical poisoning. Future development must address these threats, and in rice management particular attention should be paid to pesticide use and habitat destruction.

The Chinese and Cambodian studies have so far yielded very interesting results and insights. Further analysis and follow-up are now required, as the studies are limited to certain areas and time spans. The Vietnamese and the Laotian studies are expected to be completed in 2002, and this type of study will then be expanded to other countries in the region. Findings are furthermore expected to serve as important background information for activities in other regions such as West Africa, where a joint FAO/WARDA Workshop on Integrated Irrigation and Aquaculture is planned to be held in July 2002 in Bouaké, Côte d’Ivoire.

The initial goal of these studies - i.e. to document the availability and use of aquatic organisms in rice-based farming and to raise awareness of all stakeholders about the aquatic biodiversity in rice - has been partially achieved through the participatory process followed in the studies. However, further activities are planned in the form of documentation and workshops so as to make a larger audience aware of the results.

Studies in this integrated area of rice farming and fisheries require cooperation and exchange between the different disciplines. Close collaboration within FAO is expected to continue, particularly among the Agricultural Divisions dealing with plant production and protection and with land and water use. The findings are expected to be important for upcoming meetings, such as the newly established intergovernmental Sub-Committee on Aquaculture of the Committee on Fisheries (which will meet for the first time in April 2002 in Beijing), and for external partnerships and collaborative programmes, in particular for a recently initiated joint activity between FAO, DFID (Department for International Development, UK), VSO (Voluntary Service Overseas) and NACA (Network of Aquaculture Centres in Asia-Pacific), entitled Support to Regional Aquatic Resource Management (STREAM).


Aarnink, W., Bunning, S., Collette, L. & Mulvany, P. 1999. Sustaining agricultural biodiversity and agro-ecosystem functions - opportunities, incentives and approaches for the conservation and sustainable use of agricultural biodiversity in agro-ecosystems and production systems. In Proceedings of a FAO/CBD International Technical Workshop, 2-4 Dec. 1998, FAO, Rome.

Demaine, H. & Halwart, M. 2001. An overview of rice-based small-scale aquaculture. In IIRR, IDRC, FAO, NACA& ICLARM. Utilizing different aquatic resources for livelihoods in Asia: a resource book, p. 189-197. International Institute of Rural Reconstruction, International Development Research Centre, Food and Agriculture Organization of the United Nations, Network of Aquaculture Centers in Asia-Pacific and International Center for Living Aquatic Resources Management. 416 pp.

Gregory, R. & Guttman, H. 1996. Capture and culture ricefield fisheries in Cambodia. In Nesbitt, H.J. ed. Rice production in Cambodia, p. 159-173. Cambodia-IRRI-Australia Project, Phnom Penh, Cambodia.

Halwart, M. 1999. Fish in rice-based farming systems - Trends and prospects. In Tran, D.V. ed. Proceedings of the 19th Session of the International Rice Commission, 7-9 September 1998, Cairo, Egypt. FAO, Rome.

Appendix - Traditional use and availability of aquatic organisms in rice field ecosystems of Kampong Thom Province, Kingdom of Cambodia


The Great Lake ecosystem

The Tonle Sap, also known as the Great Lake in central Cambodia is the heart of Cambodia’s fresh water fisheries. It is the largest fresh water lake in Southeast Asia and one of the richest freshwater fishing grounds in the world. Its hydrological characteristics are mainly influenced by the Mekong River who fills the lake during the rainy season through the Tonle Sap River, reversing its flow to the sea for several months. In the dry season, the lake covers an area of 2’500 - 3’000 square kilometers at an average depth of only one to two meters. In the rainy season the area increases to 9’000 -14’000 square kilometers and the depth reaches 9 - 11 meters.

Abelt of freshwater mangroves known as the flooded forest surrounds the lake. This gradually changes to bushes and finally grassland with increasing distance from the lake. The floodplains are surrounded by low hills, which are naturally covered with evergreen or deciduous dry Dipterocarp forest. The figures below show a transect from the lake to the hills at the end of the wet and the dry season respectively.

The flooded forest and the surrounding floodplain are of great importance for Cambodia’s fresh water fisheries. At the beginning of the flooding, many fish species leave the lake and the larger ponds for the forest to spawn. The young fish then move out into the floodplains to feed. At the end of the flooding, the fish follow the receding waters back to the lake and through the Tonle Sap River to the Mekong.

Rice field fisheries in Cambodia

Traditionally the people living around the lake were planting rice varieties in those areas subject to deep flooding that could cope with the high water levels by elongating their stems up to five meters with a maximum growth of ten centimeters per day. This floating rice was broadcast at the start of the rainy season on previously ploughed fields in areas naturally covered with bushes or grass. At greater distance to the lake were the flooding is not as deep, normal wet rice varieties are transplanted into the fields once the flood has reached them.

At the end of the flooding, rice is planted in the receding water, which is sometimes held back by dams for that purpose. The water present in the soil has to be enough for the development of this so-called “receding rice”. Controlled irrigation, which in Cambodia was present during the Angkorian period, is nowadays the exception. While pesticide and fertilizer use plays a minor role in the traditional floating rice varieties, it is more common in transplanted receding rice with modern varieties.

As a saying goes in Cambodia “once there is water, there is also fish” and this is especially true for the different rice field ecosystems of the country. The importance of the rice field fisheries however is often underestimated. The Cambodian Office of Fisheries has in the past mainly concentrated on the management of the fishing lots in the great lake. This is due to the revenues generated through the auctioning of these lots for a period of three to five years to business people for commercial exploitation.

Statistics on the productivity of these commercial lots are available and fairly accurate. Instead, for rice field fisheries the figures available differ widely, depending on the area where and the year when the respective study has been conducted. Figures vary from as low as 25 kg (Spiller, 1985) through 100 kg (Gregory et al.) up to 150 kg per ha and year (Ali, 1990). Ahmed et al. (1998) use figures from 25 - 61 kg per hectare and year to estimate the annual production of Cambodia’s rice field fisheries. Multiplied with the 1.8 million hectares of Cambodian rice fields they reach an annual production of 45’000 to 110’000 tons, amounting to 15 - 25 percent of Cambodia’s total annual fish catch. This extrapolation however is a rather unreliable method of assessment, since the heterogeneity in agro-ecological conditions and differences in the microenvironments of rice fields result in a variable productivity (Little et al., 1996). Generally speaking, there is a tendency to underestimate the importance of rice field fisheries since they tend to yield only small amounts of fish at a time, but on a regular basis and for many people involved.

Also the diversity of aquatic organisms found in the rice field ecosystem varies according to the place where and the year when the respective study was conducted. Shams and Hong find 35 fish species in a study conducted in Kampong Thom Province in 1998, Gum finds 39 fish species during a survey in Battambang 1997. Not restricted to rice field ecosystems, Rainboth (1996) reports 500 species of fish for Cambodia, stating that the real number is certainly greater and perhaps even much greater.


Scope of the study

This study was conducted from the middle of September to the middle of December 2001 in Kampong Thom Province, Cambodia. Samples of fish and other organisms from the rice field ecosystems have been taken at eight different locations in three of the eight districts of Kampong Thom Province: Stoung, Stueng Saen and Santuk. Two of the places were located closer to the Great Lake with direct access to the flood plain, the other ones at various distances from it along highway No. 6.

Along with the samples, information has been collected on the availability, the tools used for collecting and the ultimate use of each species along with the peoples’ preferences among the different species. Any additional information found has been added under the heading of traditional knowledge and observations.

Limitations of the study

Due to the start in the middle of September, the beginning of the fishing season has been missed. No attempt has been made to measure the weight of fish caught by the fisher-folks involved in the study, since the day to day variability of the fish catches was too great and the scope of the study limited to a short time and a few places only.

Certain groups of animals are underrepresented here, since according to the local people their season is either before the start or after the end of the study. Important here are water insects, crabs, and frogs. And while the study was started focussing on aquatic animals collected from the rice fields, aquatic plants were added to the scope only later.

Methods used

To collect information from the local people, several different methods have been used in a time sequence. The start was made by Participatory Rural Appraisals (PRA’s) in three villages. With the initial information collected in this way, the second step was the collection of species caught by the local people. At the end of the season, single and group interviews were used to verify the information previously collected.


As the first step, PRA’s were conducted in three villages of Kampong Thom Province: Doun L’a in Stoung District, Panha Chi in Stueng Saen District and Tboung Krapeu in Santuk District. In this warming up exercise, the people were asked during a village meeting to enumerate the aquatic animals they collect from their rice fields, their uses etc. At the same time it served as an introduction to the people to ensure that they know what the purpose of the following regular visits in their village would be.

Species collection

During the time from the end of September 2001 to the beginning of December 2001, the researchers went to the field almost every day. The maps in the annex show the villages were the collections were made. The collection points were the sites where people went to fish in or near the rice field ecosystems. The drawing below shows a typical situation in Kampong Thom: the road is built on a dam. Soil for it has been excavated on both sides, forming canals left and right of the road. During the rainy season these canals are filled with water and directly connected to the surrounding rice fields. People gather to catch fish near bridges and culverts, which are like a bottleneck for water, and fish.

At points like this as well as within the rice fields specimens were collected and pictures of the various species encountered were taken. Samples of every organism smaller then 15 cm were collected and preserved. The pictures taken were developed locally and then scanned and processed with the computer.

While collecting the specimen, the fisher-folks were asked to give information on the availability of the species found as well as on their uses and the preferences of the people for them. At the same time the various fishing tools used were documented.


At the end of the fishing season, the information collected previously was consolidated and verified in single and group interviews conducted in the villages were the collections were made. Since the people were by then already familiar with the researchers, no initial shyness had to be overcome. People were talking freely about the aquatic animals they used to collect and also about the difficulties and problems they encounter.


Species found

The species found have been categorized into seven groups: fishes, reptiles, crustaceans, amphibians, mollusks, insects and plants. They are discussed separately below.

Fishes: they are by far the most important group, both in species diversity and in importance for the local population. For most Khmer people fish is the primary source of protein and fish either fresh or processed is part of every meal. The fishing season for rice field fisheries in Kampong Thom starts in August and ends in December when the water recedes and leaves the fields dry.

In the course of this study 70 different species have been found in the rice field ecosystem. They were identified as far as possible, using Rainboth’s field guide. Of these 70 species, 25 were abundant and another 12 species were still commonly seen in the catches. As most favored rated were 24 species, however only four of them were abundant as well: the chevron snakehead, broad-headed and walking catfishes and the swamp eel. Eleven of the most favored species are considered rare. The availability of the fishes changed in the course of the fishing season, some were more common at its beginning, others were found rather later. Some fishes came in waves, abundant one day and rare the next. The local people claim, that they have seen the eggs of four species within the rice fields, three of them among the most favored fish: the two catfishes mentioned above and the chevron snakehead. The fourth species is the climbing perch, found abundantly but not as well liked as the other three.

Most fish is eaten fresh, but there are a number of ways to preserve fish. Atypical Khmer fish preserve is Prahoc, fermented fish paste. It is made from the least favored fish or from those left over that cannot be sold as fresh any more. Other ways to preserve fish it to place it in salt, to dry it or to smoke it over wood fire. The latter results in a highly priced product, which is seen less and less due to the lack of firewood needed for the processing. Two other types of processed fish command high prices in the markets: mam and trey ngiat. Both are made from the filet of large fishes like the snakeheads, marble fishes, catfishes and other favored species. Mam is made by fermenting the filet while trey ngiat is sun dried.

Reptiles: Seven snakes and one turtle were found during this study. Since no literature on reptiles is locally available, no proper identification could be made. Snakes are well liked for food and in some areas have been seriously reduced through over-collection for sale to the cities. From the seven snakes found only one was found in abundance, two more were commonly seen, especially in the deep water rice fields of Roluos. Snakes are usually eaten fresh, only one snake has been reportedly used as a traditional medicine: preserved in alcohol it is said to enhance the appetite. Snakes can be found in the rice fields throughout the year.

The turtle found is considered uncommon, it has been seen only twice within the course of the study and only in Roluos. It is considered a delicacy and it is also reportedly used as a traditional medicine. A very destructive way of hunting turtles has been described for the dry season: the flooded forest - then dry - is set to fire and the turtles would come out of their hiding places to escape. In the rice fields, turtles can only be found in the months from August to December, during the rest of the year they are found in the flooded forest.

Crustaceans: Five species of crabs and one shrimp have been collected during the study. In his study on rice field crabs van Amerongen stated that the rice field crabs found by him all belong to the same genus Somanniathelphusa. He writes, that morphological differences could not be observed, only color and size vary. For the crabs found during this study at least some morphological differences can be seen, thus a question mark has been added to the generic name. All but one of the crabs are abundant, however, they are not well liked. Commonly used as bait or as feeds for pigs, people would eat them in time of scarcity. They are generally considered a pest in the rice fields were they feed on the rice plants and can do considerable damage to a newly planted field. They are chiefly collected from June to December.

Also the shrimp is found in abundance, it is used for food either fresh or dried or processed into shrimp sauce. Shrimps can be found in the rice fields from September to December.

Amphibians: Only two amphibians were found in the course of the study, one toad and one frog. Since literature on amphibians is not available locally, no identification could be made. Both species are reportedly abundant, however, they are found chiefly early in the rainy season from June to September. The frog is very much liked for food and during the season commonly seen in the markets. The toad is used as an anthelmintic for cattle but it is also eaten. It is sometimes exported to China.

Molluscs: One snail was found within the rice field ecosystem, other snails and also shells were only collected from the rivers and the lakes in the study area. While it is liked better then crabs it cannot compete with the fish that can be found in the rice fields. It is then rather used as bait to catch fish or fed to the pigs. Also for the snail, no identification could be made because of the lack in literature available locally. It is collected in the rice fields from June to December.

Insects: Two water insects were found to be of importance for the local people during this study: a giant water bug from the Belostomatid family and a water beetle probably from the Dytiscid family. Both of them are used as finger foods and both command good prices in the markets during their season which follows the season for frogs: from September to October. The giant water bug is also used as traditional medicine: mixed with alcohol it is given to women after birth. The water beetle is abundantly available; the giant water bug is still considered common.

Plants: Apart from the rice itself there are a number of other plants found within the rice field ecosystem, which are utilized by the people. In the course of this study, 13 species have been recorded, six of which are marketed. The other seven species are chiefly used as feeds or consumed locally they have no market value. All plants recorded were found in abundance, some during the time of the flood, others more towards its end.

The plants could be identified using Dy Phon’s Dictionary of plants used in Cambodia and the handbooks of the PROSEA series.

Collection methods used

Farmers and fisher-folks of Kampong Thom Province use a wide variety of different implements and techniques to collect fishes and other aquatic organisms from the rice field ecosystem. In the course of this study, 26 techniques to catch fish have been recorded. They can be subdivided into four main categories:

Implements that catch fish with baited hooks: they are rather selective in the species caught with them since some species are more attracted to a certain kind of bait then others. Four different types can be distinguished here, two of which are used actively, the other two are attached to shrubs or sticks and checked at regular intervals.

Traps: these are usually less selective and apart from fish a variety of other aquatic animals like frogs, snakes, crabs and shrimps can be caught with them. Often made from woven bamboo the selectivity is defined by the distance between the bamboo strips. However, also traps for specific fish exist like the different eel traps. All together, six different types of traps can be distinguished.

Nets: like the traps, nets are little selective concerning the species caught; the main selectivity is given by the size of the mesh. Six different types of net were observed during the study. Also here a distinction can be made between nets used actively like a cast net and nets placed and left like the gill nets. It could be observed, that for the gill nets used in Roluos larger mesh sizes were preferred since in this area plenty of fish is still available. In areas further away from the flooded plains like Tboung Krapeu or Tuol Vihear smaller mesh sizes were employed to catch all but the smallest fish. In these areas, fishes are not as abundant as in the other areas and many juveniles have been seen in the catches, a clear indicator for over-use of the resource. Another particular problem is that old unusable gill nets are not collected and destroyed but left at their position in or near the water. They are a hazard to many water birds, which get caught and die in them.

Others: Here all techniques and implements that do not fit into the three categories above have been lumped together. They are usually characterized as active techniques such as digging, emptying depressions and catching fish with a spear or by hand.

An additional, illegal and very destructive, unfortunately by now widespread, technique has established during the last decade, the electro shock fishing. It is the least selective method of all, killing every organism wherever it is used. It is blamed along with the destruction of the flooded forest for the great reduction of the fish catches during the last years.

The implements used to catch aquatic animals can also be grouped according to their use in either shallow or deep water. They can thus also be assigned to periods of time when they are commonly used: a succession of different fishing tools could be observed along with the changing levels of the flood waters in the area.

Most of the implements used to catch fish are traditionally used either by men or women. The elder children, mostly the boys would already support their father in the use of typical male implements, smaller children and girls would accompany the mother in her collecting activities. While both men and women catch fish and crustaceans, plants, snails and insects are rather collected by women and children. Since reptiles and amphibians are typically caught with fish traps, men are the ones collecting them.

Some farmers have established ponds in or near their rice fields. These are not usually stocked actively with fish but the fish withdraw into them from the surrounding rice fields when those are drying up. Some farmers would also place small fish caught during the end of the flooding into their pond to allow them to grow bigger. Most farmers however do not have such a pond, some claim, that the soil in their area is not suitable, others explained that they cannot afford the time needed to dig such a pond deep enough to retain water throughout the year. They declared that if an organization would support them they would readily agree to have a pond.

Traditional knowledge and observations

People have accumulated over time a profound knowledge about fishes and their behavior. They have very accurate ideas about where what kind of fish can be found. A common observation is, that many fishes lay their eggs in the flooded forest or in the flooded shrubs surrounding their rice fields. The young fish then come to look for food in the rice fields and the flooded grasslands. Once the trees and shrubs are gone in an area, the fishes are getting less.

It has been observed by the local people that the fish catches have been greatly reduced over the last two decades. Some fish species have disappeared all together. This is blamed partly on the increasing use of illegal fishing tools like electro shock but also on the destruction of the flooded forests surrounding Tonle Sap Lake. Also the increasing number of people living in the area is given as a reason for the smaller fish catches every year: more people have to share a resource that is getting less. And while the farmer fishermen of old caught fish mainly for home consumption nowadays a more market-oriented approach drives people to catch more fish for sale on the markets.

An average family of five persons would consume about one kilogram of fresh fish every day during the fishing season. The same family would need about 20 kg of Prahoc to eat in the dry season. Everything caught above this would be sold in the market. Depending on the fishing tool employed, a farmer-fisherman can catch 15 to 20 kg of fish on a good day. The average fish catch during the fishing season is less than 10 kg per day. For comparison: a commercial operator blocking - illegally - a medium sized river to the migrating fish can catch about twelve kilogram of fish in less then ten minutes.

Since the beginning of the 1990s a fish disease called Dambao is reported to occur every year with varying strength. Starting in January until March the fishes in the ponds and lakes start dying, smelling worse then ordinary dead fish. The people say that these fish cannot even be used to make Prahoc. The worst year when this disease has hit the area until now was in 1995 when most lakes were transformed into stinking pits. Once the rains start, the disease disappears. The people claim, that the increasing use of fertilizer and pesticides in the receding rice cultivation is to blame for this phenomenon. Local people believe that on Buddhist prayer days many fish can be caught. Since Buddhist prayer days coincide with the phases of the moon, this is supported by another observation: fish like the moonlight, they are playful in moonlight and are easily caught with the gillnet at the time of the full moon. When rain is coming up however no fish can be caught. Only when the rain starts falling the fish would come out of their hiding places.

During certain times of the day, very little fish is caught. Asked for the reason, a fisherman told that the fishes are now in the rice fields looking for food. They would come out later to play in the canal where they can be caught with the cast-net.


The rice field ecosystem is of major importance for the supply not only of rice but also of protein and of vegetables for the local population. One-sided development towards increasing yields of rice through intensification and the use of chemical fertilizers and pesticides will give the people more rice to eat, but it will take them the fish and the vegetables to go along with. The introduction of fishponds stocked with introduced fishes, as a remedy against the loss of the naturally available fish is not likely to have great success at the sites where this study took place. It is at best difficult to maintain a fishpond during the flooding period when most of the area surrounding the great lake actually becomes part of it. And especially the poorest people living around the lake have to rely on wild capture fisheries since they do not have rice fields of their own - and thus also no land to establish an own fishpond.

A more promising approach seems to be a participatory development approach that addresses all the needs of the local people through locally developed natural resources management plans and a more holistic view of a system that has catered the needs of the people for many generations.


Ahmed et al. 1998. Socio economic assessment of freshwater capture fisheries of Cambodia. Report on a household survey, MRC/DANIDA/DoF. Management of the freshwater capture fisheries of Cambodia.

Ali. 1990. Some ecological aspects of fish population in tropical ricefields. Hydrobiologia, 190: 215-222.

Dy Phon. 2000. Dictionary of plants utilized in Cambodia. Imprimerie Olympic, Phnom Penh.

Gregory et al. 199?. Poor in all but fish. AIT Aquaculture working paper No. 4, Cambodia, Asian Institute of Technology, Bangkok.

Gum. 1997. Consultancy report on fisheries development in Northwest Cambodia, Cambodia Rehabilitation and Regeneration, CARERE UNDP/RGC.

Little et al. 1996. In Wild fish component of AIT Aqua Outreach. AIT Aquaculture Aquaculture Section, Asian Institute of Technology, 1998.

Rainboth. 1996. FAO species identification field guide for fishery purposes. Fishes of the Cambodian Mekong. FAO Rome.

Shams & Hong. 1998. Rice field ecosystem biodiversity - Resources and benefits. Deutsche Gesellschaft fuer technische Zusammenarbeit (GTZ).

Spiller. 1985. Rice cum fish culture: Environmental aspects of rice and fish production in Asia. Report FAP/WP-15. FAO Office for Asia and the Pacific, Bangkok.

van Amerongen. 1999. The rice field crab - a short study on its role as a pest to rice culture. FAO Rome.

[41] Particular thanks are due to the study collaborators in Cambodia, T. and P. Balzer with Sibura Pon, and in China, A. Luo with J. Margraf.

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