Agriculrura/ Adminisrrnrion 10 (1982) I-I 1

TRADITIONAL INTEGRATED FARMING SYSTEMS AND RURAL DEVELOPMENT: THE EXAMPLE OF RICEFIELD

FISHERIES IN SOUTHEAST ASIA

KENNETH RUDDLE

National Museum of Ethnology, Senri Expo Park, Suita, Osaka 565, Japan

(Received: 10 April, 1981)

SUMMARY

Ricejield capture and culture fisheries, an ancient practice in Southeast Asia, probably developed concurrently with rice cultivation. Some twenty main species of fresh- and brackish water jish are currently cultivated or caught in the region’s ricejields. But despite their widespread occurrence and antiquity, ricejeldfisheries are poorly documentedatid remain little understood scient@ally. Although severely constrained by the demands of modern rice cultivation technology and having experienced dramatic declines in the past two decades, the integratedfarming ojjish and rice holdsgreatpotentialfor supplying low-cost animalprotein in’ the tropics and

for increasing the income of small-farm households.

INTRODUCTION

The integrated cultivation of rice and fish, the two dietary mainstays, is a traditional practice in many parts of South and Southeast Asia, and one that represents a sophisticated use of limited resources and abundant family labour. Although ricefield capture and culture fisheries have declined seriously throughout the region in recent years-in large part as a consequence of the spread of high yielding varieties of rice and their associated technologies-the growing interest of scientists and rural development administrators in integrated farming systems has stimulated a re-evaluation of the potential of ricefield fisheries to satisfy part of the demand for relatively inexpensive animal protein for low-income rural and urban populations.

Agricultural Administration 0309-586X/82/0010-0001/$02.75 0 Applied Science Publishers Ltd, England, 1982 Printed in Great Britain

2 KENNETH RUDDLE

All techniques of flooded-field rice cultivation create aquatic conditions during periods of the cultivation cycle and such conditions, which may last for only a few weeks or can involve continuous flooding for many months, during which marsh- like habitats can arise, permit the development of an aquatic fauna in the ricefields and their associated irrigation and drainage canals and ditches. The human exploitation of the rich, naturally occurring ricefield fauna, which includes, inter alia, aquatic birds, frogs, snails, fish and shrimp, is probably as ancient as rice cultivation itself; i.e. some 6000 years BP in parts of South and Southeast Asia.

Despite its long history and importance in many local economies of rural Asia, notwithstanding the urgent need to complement the rice staple with animal protein produced by cheap and technologically simple means, and in spite of the wide availability of suitable habitats, only an estimated 0.65 %, or 136,000 ha of 21 million ha, of the irrigated ricefields in Southeast Asia are also exploited for the cultivation of fish.’ But virtually everywhere that irrigated rice is grown fish are captured in flooded fields and a wide range of species is either cultivated or captured in the region, the principal of which are Climbing perch (Anabas testudineus), Tawes (Barbus gonionotus), Milkfish (Chanos chanos), Common carp (Cyprinus carpio), Kissing gourami (Helostoma temmincki), Cock-up (Lutes calcarij’er), Grey Mullet (Mugil sp.), Snakehead fish (Ophicephalus sp.), Gourami (Osphronemus goramy), Nilem carp (Osteochilus hasselti), Java and Nile tilapia (Tilapia mossambica and T. nilotica) and Sepat siam (Trichogaster pectoralis).

This paper describes two representative examples of ricefield fishery systems, examines the advantages of, and contraints on, such systems and points out the research needed to plan for their development.

RICEFIELD FISHERY SYSTEMS

Ricefield fishery techniques, although varying widely in detail among the countries of Southeast Asia, may be broadly grouped into capture systems and culture systems (Fig. 1).

Capture systems, the simplest type, with few, if any, inputs, use a wide variety of techniques and tools to take naturally occurring fish from ricefields and their

<

Capture systems Ricefield fisheries

<

Concurrent cultivation of fish and rice

Culture systems Alternate cropping

Rotational cultivation of fish and rice < Intermediate cropping

Fig. 1. Principal ricefield fishery systems

TRADITIONAL INTEGRATED FARMING SYSTEMS AND RURAL DEVELOPMENT 3

associated irrigation and drainage channels. There is little or no modification of the field under this type of system. Usually, the field is not specifically adapted to retain the fish, but in some instances small sumps are dug to concentrate them in the lower portion of a group of fields. Predatory fish are usually predominant in the harvest of capture systems and in Southeast Asia consist of such common species as Ophiocephalidae (snakeheads) and other air-breathing species like Anabantidae (Labyrinth fish), Clariidae (air-breathing catfish) and Heteropneustidae (Stinging catfish)2.

In Malaysia, the success of capture systems improved with the introduction of Trichogaster pectoralis from Thailand, which gradually became the main fish cropped. The other main species taken in Peninsular Malaysia are Clarias macrocephalus, Ophiocephalus striatus and Anabas testudineus.3 Although yields vary according to soil type and fertility and water pH, they average 135 kg/ha after 6610 months and range from lOkg/ha to 400kg/ha.4

As the term implies, culture systems involve the deliberate modification of ricefields and their stocking with one or several species that are cultivated to produce a desired product. Other species, not deliberately stocked, usually enter the field through the water supply network and are raised along with the principal fish crop(s).

Culture systems may be further differentiated into concurrent types, in which fish and rice are raised together, and rotational types, where fish and rice are not cultivated concurrently. Two types of rotational system occur: alternate cropping, under which a single crop of fish is stocked in the paddy after a single annual crop of rice has been harvested, and, under double rice-planting systems, intermediate cropping, in which fish are cultivated during the period between the harvest of the first rice crop and field preparation for the second.

A typical monocultural system is the Indonesian minapadi, the main objective of which is rice production but which involves the closely organised, concurrent cultivation of rice and Common carp (Cyprinus carpio). The cultivation of the fish is carefully synchronised with the sequence of activities and operations needed to produce a crop of rice. Under the system practised in the Cisaat District of Sukabumi Regency, West Java, two crops of traditional rice varieties are produced each year, together with eight harvests of fish. This system is closely linked with fish pond production; six of the harvests being for fry or fingerlings for pond stocking and only two producing table fish for both household consumption and sale (Table 1)‘.

The rate of return from a polycultural minapadi, in which Common carp, Tawes and Java tilapia are cultivated in ditches around the perimeter of the ricefield, is illustrated by the example of a 0.4 ha farm at Kertamukti Village, Pedes District, located in the coastal lowlands of Karawang Regency (Table 2). Despite loss rates of 42.3 % for carp and 59.5 % for Tawes, attributed to predation, the profits realised were high-just over 18 and 8 times the investment in fingerlings, respectively (costs

4 KENNETH RUDDLE

TABLE 1 S.EQUENCEOFOPERATI~NSIN~~NCURRENTRI~E--FISH(~~MM~N CARP)C~LTIVATI~N,SUKABUMIREGENCY,

WEST JAVA, INDONESIA

Month Activity Inputs (Fish) Outputs (Fish) Remarks

July

July

July

August

Sept.

Sept.

Oct.

Clean, till and prepare field for next rice crop. Repair dykes, maintain irrigation and drainage system. Prepare ditches for fish culture.

Field flooded. Carp fry stocked for 20 days. ,

First Fingerling Harvest

Transplant rice to field. Raise water level in field. Stock fry 3 days after transplanting.

Second Fingerling Harvest

First weeding of rice. Maintenance of fish culture ditches. Fertilise rice. Stock field with fingerlings.

Third Fish Harvest

Field drained, weeded and fertilised.

Field flooded. Field stocked with

fingerlings.

Nov. Fourth Fish Harvest

Field drained Rice Harvest. Field fallowed for one month.

Total of 10 man-days labour ; one day for preparing fish cultivation ditches.

7 day old fry (l- 1.5 cm long) from farmer’s hatching pond.

7 day old fry.

Stocking rate 6000/ha 3 days after fertilising field.

Prepared rice field with ditches, 50 cm wide and 25-40 deep for fish, around periphery and across centre of field.

Fingerlings 27 days old (33Scm long).

Fingerlings 37 days old (5-7 cm long).

-

Fish 2 months old (8-12cm long).

Five adult males working for 2 days.

Stocking rate 30,000 fry per hectare.

Mortality/loss rate unknown.

Stocking rate as above.

Mortality/loss rate unknown. Stocked in farmer’s rearing ponds or sold.

Stock derived from Second Harvest.

Mortality/loss rate unknown. Larger fish stocked in rearing ponds or sold to other pond owners.

Rice at flowering stage.

- Smaller fish from -

Third Harvest (5-8cm long) stocked at rate or lOOO-2000/ha.

80- 100 kg/ha (total Mortality/loss rate weight) harvest 3- unknown. 4 weeks after stocking.

TRADITIONAL INTEGRATED FARMING SYSTEMS AND RURAL DEVELOPMENT 5

TABLE l-contd.

Month Activity Inputs (Fish) Outputs (Fish) Remarks

Dec. Field preparation - begins for second rice crop and concurrent fish cultivation (as above).

TABLE 2 RATE OF RETURN ON THE FISH COMPONENT OF minapadi SYSTEMS, KARAWANG REGENCY

Species

Carp Tawes Tilapia

Total

Stocking Number cost stocked ($1

1200 22.9 3000 29.12

30 (kg) -

Harvesting Market Number Total price

harvested weight (kg) (Ws)

692 311 1.13 1215 360 064

370 0.48

1101 -

Total income

($1

419.09 233.01 179.61

831.71

of supplementary feed, ditch construction and maintenance labour are not yet available). The decision to convert a simple ricefield to rice-fish cultivation proved amply justified in this case. Hitherto, the farm was yielding rice at the rate of 2.4 MT/ha (field dry weight), but in 1979, with the addition of fish, the rate of rice yield declined to 2.04 MT/ha (actual yield was 1.4 MT) owing to the reduction in the area devoted to rice, but the fish produced, at current market prices, the field dry rice equivalent of 10.97 MT/ha, with an actual production of 6.862 MT rice equivalent.

A more fully integrated farming system in West Java is the surjan in which the farmer seeks to optimise the production of rice, fish and dryland crops within a single farm unit. Field preparation is similar to that for minupudi, except that the dykes are wider, to support dryland crops (beans, chili peppers, cucurbits and papaya, and around the borders of the farm, coconut, ipil-ipil and bananas). Commonly, polycultural fish production is practised in the surjan. In the example studied at Kutagandok Village, in the coastal zone of Karawang Regency, Common carp, Tawes and Java tilapia are intentionally stocked and cultivated together, along with catfish (Clurias batrachus) that enter the fields with the irrigation waters.

The example studied is a farm of 0.9 ha, developed into a surjan in 1979. Because the average rice production per harvest on this farm was exceptionally low for the area (2 MT/ha compared with the regional average of 3-4 MT/ha), the fields were adapted for minapadi production rather than for rice cultivation alone (Table 3). Despite a loss rate of 38.77 % for Common carp, total fish production on this

6 KENNETH RUDDLE

TABLE 3 RATE OF RETURN ON THE FISH COMPONENT OF Sllrjan SYSTEM, KARAWANG REGENCY

(All prices have been converted to $US from Rupiah at Rp. 618 = $1 .OO. No data for dryland crop production available yet for this farm.)

Species Stocking Harvesting Market Total Number cost Number Total price income stocked (9 harvested weight (kg) ($/kg) ($)

Carp 5490 104.53 3349 219 2.10 462.15 Tawes 400 3.88 500 65 0.80 52.59 Tilapia 600 1.21 I” 0.40 2.15 Catfishb - 10” 1.29 16.18

Total f&470 203.46’ 301 533.67

’ Weighed for marketing, not counted. b Enters with irrigation waters. e Includes $29.12 for supplementary feeding for 3 months and $64.72 as labour costs for digging 1200 m2

of ditches for fish cultivation.

holding yielded a profit of 160 % on the original investment (excluding the cost of maintenance labour). Expressed as ‘field-dry rice equivalent’, this equals 2.69 MT, which amply compensates for the 240 kg estimated reduction in rice production as a consequence of digging ditches for fish cultivation. When combined with the actual rice production of 2.3 MT (field dry weight), the farm’s productivity was equivalent to 4.99 MT field dry rice-well in excess of the regional average.

ADVANTAGES OF RICEFIELD FISHERIES

In addition to providing economic and dietary benefits to the farm household, despite the higher cost of inputs, and utilising more fully available ecological niches, the joint cultivation of rice and fish in paddy fields enhances the yield of both rice and fish. But, on the other hand, certain aspects of rice technology are inimical to fish raising, and vice versa some facets of fish cultivation are detrimental to the rice crop.

Although the precise reasons are not yet clear, it is well established that in Southeast Asia the cultivation of fish in paddies increases rice yields by as much as 15 % and that rice yields improve even more under the polyculture of fish species. This may result from the increased aeration of the water caused by movements of the fish, which also appear to increase the rate of tillering of rice plants6,7. And certainly, soil fertility is enhanced by the decomposition of fish excrement and the remains of supplementary feed fed to the fish, together with the increased amount of fertiliser required when fish are cultured in the ricefield. Moreover, when herbivorous fish, such as Common carp, Tawes and Java tilapia, are stocked in the field, weed control is enhanced, thus improving rice yields and reducing labour inputs (the latter, however, is not particularly desirable in parts of Southeast Asia).

TRADITIONAL INTEGRATED FARMING SYSTEMS AND RURAL DEVELOPMENT 7

In field experiments in West Java, Common carp were found to reduce weed growth by 30 % during the period between transplanting of the rice and the first weeding. Polyculture of fish appears to reduce weed infestation even more. In some instances fish present in ricefields consume insects and their larvae which damage rice plants as well as the vectors of diseases harmful to humans3. But fish sometimes damage young rice plants.

Where fish cultivation is well integrated into local rice economies it plays a major role in augmenting household incomes. As shown in West Java, for example, the value of fish produced in ricefields often equals-and not infrequently exceeds- that of the rice harvested. Incomes derived from paddy field fish culture in Central Thailand are similar3, and in Peninsular Malaysia the value of ricefield fisheries is sometimes as much 50 % that of the rice’. Clearly, the joint cultivation of fish and rice is a rational form of land use, particularly among impoverished tenant farmers when land holdings are small, rents extremely high and lease conditions onerous- the prevailing conditions throughout much of Southeast Asia.

PRINCIPAL CONSTRAINTS ON RICEFIELD FISHERIES

Certain disadvantages are inherent in rice-fish cultivation systems, as a con- sequence of the management requirements of rice, and throughout Southeast Asia, agricultural policies emphasise rice production; thus paddy-fish cultivation must be adapted to the needs of the rice crop. The principal constraints are the toxicity of agricultural chemicals required by HYV rice and the provision of a regular water SUPPlY.

Pest infestation, a major hazard in rice production, is combated increasingly by the application of chemical pesticides, some of which may be toxic to fish and/or their consumers. Moreover, the persistence of pesticides in the ricefield environment may be a long-term constraint on fish cultivation. But when insecticides such as Thiodan, Sevin or Malathion, which degrade rapidly, are used, a system that shifts fish back and forth between pond and paddy could prove suitable. Pest manage- ment by chemicals is a major constraint on ricefield fish cultivation. Combined cultivation, when this type of rice technology is used, will only be effective if insecticides are used sparingly, applied at rootzone depth or incorporated in the soil, and if the fish can be removed from the field until the toxicity hazard has diminished. Similarly, chemicals used to control rice diseases and weeds may be hazardous to fish but, in the absence of data, this remains speculative.

Fish cultivation in ricefields requires that N fertiliser application be increased by some 50 %. Incorrect application leading to high N concentrations in water may harm fish growth.

Successful fish cultivation in ricefields requires a standing water depth of 15-20 cm in the paddy and 50-60 cm in the ditches. Thus, a reliable supply of water

8 KENNETH RUDDLE

beyond that required for rice-growing must be ensured throughout the season(s) of fish cultivation. This can be a major constraint; in parts of West Java, for example, centrally controlled water supply is geared to the needs of rice, not fish production, and it is cut off completely during the fallow month. Although water may be stored in ditches for use during this period, the best system is one that involves a close ricefield-fishpond symbiosis. Competing demands for water from other agricul- tural users, as well as from industrial and domestic consumers, are also increasingly problematical.

Constraints are introduced by the rice variety cultivated, HYVs maturing in 1055125 days compared with some 160 days for traditional varieties. This may present problems in growing fish to harvestable size although it does not inhibit the cultivation of fingerlings for later stocking in fish ponds.

Finally, poor or badly timed land preparation for rice may harm fish exposed to the release of harmful substances by decaying organic material in the soil.

However, certain techniques of rice husbandry, especially the application of fertilisers and water supply, could be modified to increase fish production without lowering rice yields, thus bringing the complementarities of both crops into full playg. Constraints can be overcome also by integrating ricefield-fishpond fish culture into a symbiotic production system, as illustrated by the Indonesian minapadi systems described above (Fig. 2).

RESEARCH NEEDS

In sharp contrast to the wealth of knowledge about wet rice agriculture is the paucity of information on ricefield fisheries and the aquatic fauna of ricefields in general.

Ricefield Fishpond

Hatching

I Nursery

Fingerlings *Holding during specific rice cultivation

Grow-out A actirs ,

Grow-out Sale

Fig. 2. Relationships between ricefield and fishpond

TRADITIONAL INTEGRATED FARMING SYSTEMS AND RURAL DEVELOPMENT 9

Bibliographies of the scarce literature on ricefield fisheries and aquatic fauna have been compiled by Cache (1967)‘, Fernando et al. ( 1979)2, Baharin et al. (1979)‘O: and Temprosa and Shehadeh (1980)“, and the recent ICLARM-SEARCA (International Center for Living Aquatic Resources Management-southeast Asian Regional Center for Graduate Study and Research in Agriculture) Conference on Integrated Agriculture-Aquaculture Farming Systems, held in Manila, 6-9 August, 1979, provided a useful summary of extant knowledge and pinpointed the research and information needs for the development of ricefield fisheries.

In Southeast Asia, on-going research programmes specifically geared to ricefield fisheries are limited to Indonesia, India and the Philippines. Elsewhere in Asia there are apparently no other significant research activities in this fieldlo. Since 1976, as part of the government’s Fish Farming Integration Programme, surveys of, and case studies on, rice-fish farming systems have been undertaken by the Research Institute of Inland Fisheries, at Bogor. Experiments on improved techniques for lowland ricefield fisheries are being planned by the Agricultural Experiment Station at Depok, Jakarta, and by field stations in West and East Java. In India, where ricefield fisheries have a long history and have recently gained in importance, research programmes focus mainly on the seasonal use of paddies for fish culture (Tamil Nadu Agricultural University) and the effects of agricultural chemicals on ricefield fish (Madurai Kamaraj University). Since 1974 the Freshwater Aquaculture Center of Central Luzon State University, Philippines, has had an applied research programme i I ricefield fisheries. Present research is concentrating on the impact of pesticides on paddy fish, fingerling production in paddy fields, improved fish productionr2, and on socio-economic studies. In addition, technol- ogies and improved techniques developed at the Centre are now being pilot-tested nationwide.

Despite the important on-going research noted above, ricefield fisheries remain woefully neglected. If rice.-fish production is to achieve its potential for playing an important role in rural development in the humid tropics, basic research to solve problems and remove constraints must be undertaken, and on a wider geographical basis than hitherto.

The following areas of research should be given high priority in research programmes on integrated rice-fish farming.

System transjtivmation Integrated rice-fish farming is an ancient resource system and a traditional

activity for many small-scale farmers, and one for which a considerable body of ‘empirical wisdom’ exists. Any effort to up-grade ricefield fisheries should therefore be based to a large extent on modifying existing, locally familiar systems rather than on sweeping them aside and introducing new and generally untested techniques and technologies. ’ 3,14 Analysis of the components and functions of the traditional system to be changed and its compatibility with proposed introductions is therefore

10 KENNETH RUDDLE

essential and should be undertaken in terms of energy and materials flow, the optimal use of farm space, the temporal synchronisation of the various integrated farm activities, information diversity, particularly in management and socio- cultural inputs, and linkages with other, off-farm resource systems.

Fish species Since a wide variety of wet rice farming systems exist and since there is no

universally acceptable fish for use in integrated systems, a range of fish species suitable for rice-fish farming should be developed. Basic research on fish biology, seed supply, stocking rates and densities, stocking size and species composition for polyculture must also be undertaken, especially for those fish that are hardy, fast growing and have a relatively high tolerance for agricultural chemicals.

Principal constraints Research to overcome the constraints introduced by land preparation, the

technical requirements of different rice varieties, the use of chemical fertilisers, rice pest and disease management, weed control and the problem of a regular, adequate water supply is also of the utmost importance.

Economics Cost-benefit analyses should be conducted on a range of existing systems to

evaluate proposed technological and methodological changes. Studies of the household economics of small-scale rice-fish farms are urgently needed to evaluate the profitability of incorporating fish cultivation in the small-scale rice farm and to assess the often conflicting resource needs, risks and priorities of the poorer rural household.

ACKNOWLEDGEMENTS

This paper is based in part on fieldwork done in Java during May and June, 1980. The research was supported by the United Nations University’s Programme on the Use and Management of Natural Resources, via the Water-Land Interactive Systems Project, co-ordinated by Dr Ruddle. The assistance of Mr Koesoebiono, Mr Chair01 Mulluk and Mr Supomo Wardoyo while in the field is gratefully acknowledged.

REFERENCES

1. COCHE, A. G., Fish cultivation in rice fields: A world-wide synthesis, Hydrobiologia, 30 (1967) DD.l-4.4.

2. 'FERNANDO, C. H., FURTADO, J. I. & LIM, R. P.,,The aquatic fauna of the world’s ricefields: A general introduction and bibliography of references to the aquatic fauna of ricefields with an introduction to the ecology of ricefield fauna, Wallaceana Supplement 2, University of Malaya, Department of Zoology, Kuala Lumpur. (Mimeo.), 1979.

TRADITIONAL INTEGRATED FARMING SYSTEMS AND RURAL DEVELOPMENT 11

3. KHOO, K. H. &TAN, E. S. P., Review of rice-fish culture in Southeast Asia. Paper presented at the ICLARM-SEARCA Conference on Integrated Agriculture-Aquaculture Farming Systems. Manila, 6-9 August, 1979.

4. SOONG, M. K., The fitness of ecological niches into which fish are introduced and the survival of transplanted fish. Proceedings, Indo-Pacific Fisheries Council 3 (1951) pp. 218-27.

5. RUDDLE, K., A preliminary survey offish cultivation in ricefields, with special reference to West Java, Indonesia. Bulletin of the National Museum of Ethnology, 3,s (1980), pp. 801-22.

6. HORA, S. L. & PILLAY, T. V. R., Handbook on Fish Culture in the Indo-PacificRegion. Fish Biology Technical Papers No. 14. F.A.O., Rome, 1962.

I. SATARI, G., Wet rice cultivation withfish culture: A study ojsome agronomical aspects. PhD Thesis, Bogor Agricultural University, Bogor, Indonesia. (In Indonesian), 1962,

8. TAN, C. E., CHONG, B. J., SIER, H. K. & MOULTON, T., A report on paddy and paddy field-fish production in Krian, Perak. Bulletin 128. Ministry of Agriculture and Fisheries, Kuala Lumpur, 1973.

9. SINGH, V. P., EARLY, A. C. & WICKHAM, T. C., Rice agronomy in relation to rice-cum-fish culture. Paper presented at the ICLARM-SEARCA Conference on Integrated Agriculture-Aquaculture Farming Systems. Manila, 669 August, 1979.

10. BAHARIN b. KASSIM, ANG, K. J. & TAN, C. E., A review of the status of research and development activities in rice-cum-jish culture in Asia. Report on FAO Project No. 7-06215. Faculty of Fisheries and Marine Science, Agricultural University of Malaysia, Selangor, 1979.

11, TEMPROSA, R. M. & SHEHADEH, Z. H., Preliminary bibliography of rice-&h culture. ICLARM, Manila, 1980.

12. ARCE, R. G. & DE LA CRUZ, C. R., Yield trials on rice-fish culture at the Fresh Water Aquaculture Center. Fisheries Research Journal of the Philippines 4(l) (1979) pp. l-8.

13. RUDDLE, K. & GRANDSTAFF, T. B., The international potential of traditional resource systems in marginal areas. Technological Forecasting and Social Change, 11 (1978), pp. 119931.

14. GRANDSTAFF, T. B., RUDDLE, K., HAWKINS, J. N., FOIN, T. C. & DAVIES, W. G.: Implementing the resource systems approach to transformational development. Resource Management and Optimization 1,2 (1980) pp. 145-60.