Rice fields to prawn farms: a blue revolution in southwestBangladesh?

Nesar Ahmed Æ Edward H. Allison Æ James F. Muir

Received: 18 July 2008 / Accepted: 8 June 2009 / Published online: 27 June 2009� Springer Science+Business Media B.V. 2009

Abstract This paper examines freshwater prawn (Macrobrachium rosenbergii) farming

in southwest Bangladesh where a large number of farmers have converted their rice fields

to export oriented prawn farms, locally known as gher. The gher design potentially pro-

vides good opportunities for diversified production of prawn, fish, rice and dike crops, that

has brought about a ‘blue revolution’. The average annual yield of prawn, fish and rice was

estimated at 467, 986 and 2,257 kg ha-1, respectively. Large farmers produced higher

production due to more inputs, larger farm size and longer experience of prawn farming

than others. All farmers in different gher size categories (i.e., small, medium and large)

made a profit, with seed and feed dominating variable costs. Despite a higher production

costs per hectare, the average annual net return was higher in large farms (US$2,426),

compared with medium (US$1,798) and small (US$1,420) farms. Prawn production in

gher systems has been accompanied by a great deal of social and economic benefits. Most

farmers associate the blue revolution with increases in income and living standards. Socio-

economic benefits of the households of prawn farmers depend on resource ownership (i.e.,

farm size) and are very apparent. Nevertheless, a number of significant challenges, par-

ticularly social and environmental issues, are vital in translating its benefits effectively to

the thousands of rural poor.

Keywords Prawn � Rice field � Gher � Blue revolution � Bangladesh

N. Ahmed (&)Department of Fisheries Management, Bangladesh Agricultural University, Mymensingh 2202,Bangladeshe-mail: nesar_2000@yahoo.com

E. H. AllisonThe WorldFish Center, Jalan Batu Maung, Batu Maung, 11960 Bayan Lepas, Penang, Malaysia

J. F. MuirInstitute of Aquaculture, University of Stirling, Stirling FK9 4LA, Scotland, UK

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Introduction

In Bangladesh, freshwater prawn (Macrobrachium rosenbergii) farming is currently one of

the most important sectors of the national economy, and during the last two decades its

development has attracted considerable attention because of export potential. The fresh-

water prawn is a highly valued product for international markets; almost all prawns are

therefore exported, particularly to the USA, Europe and Japan (Ahmed et al. 2007a). In

2006, Bangladesh exported 49,317 tons of prawn and shrimp valued at US$415 million, of

which around 25% was contributed by prawn (DOF 2007).

The total area under prawn cultivation is estimated to be around 50,000 ha. Most prawn

farms (71%) are located in southwest Bangladesh, mainly Khulna, Bagerhat and Satkhira

districts (Ahmed et al. 2008). Freshwater prawn farming is expanding rapidly at an average

of 10% per annum. Approximately 1.2 million people are involved in prawn and shrimp

production, processing and marketing activities, and a further 4.8 million household

members are associated with the sector. In addition, the livelihoods of around 400,000

people, many of them women and children, are associated with prawn and shrimp fry

fishing in coastal Bangladesh (USAID 2006).

In southwest Bangladesh, the cultivation of prawns is done in modified rice fields,

locally referred to as gher. The Bengali term ‘gher’ is an enclosure made for prawn

cultivation by modifying rice fields through building higher dikes around the field and

excavating a canal several feet deep inside the periphery to retain water during the dry

season (Kendrick 1994). Gher farming is a quiet, indigenous technological revolution,

suitable for the cultivation of prawn, fish, rice and dike crops (Kamp and Brand 1994). This

innovation, combined with high prices for prawn in the international market, has led

increasing numbers of farmers to convert rice fields to prawn farms. Prawn farming in rice

fields can be considered as a method of integrated aquaculture–agriculture (IAA).

According to Nhan et al. (2007), IAA is more appropriate for resource-poor farmers who

include integration with rice or other crops. IAA farming systems are often less risky

because, if managed efficiently, they benefit from synergisms among enterprises (Lightfoot

et al. 1993; Edwards 1998). The purposes of IAA are increased diversification, intensifi-

cation, improved natural resource efficiency, increased productivity and sustainability

(Prein 2002; Ahmed et al. 2007b).

The rapid development of integrated prawn farming in southwest Bangladesh has been

likened to a ‘blue revolution’1 (Ito 2004; Islam 2007). The term ‘blue revolution’ refers to

the remarkable emergence of aquaculture as an important and highly productive agricul-

tural activity (McGinn 1998; Movik et al. 2005). According to Cunningham et al. (2004),

the blue revolution is the result of new techniques of fish farming that may contribute to

human nutrition in ways comparable to the ‘green revolution’, but may also create social

and environmental problems. Goldburg et al. (2001) noted that one way to make the blue

revolution more environmentally acceptable is to teach new methods to poor farmers. It is

being asserted just as the ‘green revolution’ transformed world agriculture in the 1960s

(Wollenweber et al. 2005).

This paper examines the blue revolution that has been brought about by export-oriented

prawn cultivation in southwest Bangladesh. It also analyzes how prawn farming brings

about widespread social and economic benefits within the area and more broadly in

1 The term ‘blue revolution’ was first used by Bailey (1985) to describe the aquatic equivalent of the ‘greenrevolution’. The blue revolution refers to the advent of new fisheries technology that helped boost the fishingcapacity of developing countries.

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Bangladesh. One important factor, resource ownership, is considered meaningful in terms

of socio-economic benefits. The aim of this paper was therefore to describe the ways in

which prawn farming communities gain from the cultivation of prawns, and how these

benefits depend on resource ownership. This description is based on published sources

together with the results of primary data collected in southwest Bangladesh.

Materials and methods

Study area

The study was conducted in Bagerhat district, a coastal area of the Bay of Bengal, situated

in the southwest part of Bangladesh (Fig. 1). Geographically, Bagerhat has been identified

as the most important and promising area for prawn culture, because of the availability of

wild fry, favorable resources and climatic conditions, including the availability of low-

lying rice fields, warm climate, fertile soil, and cheap and abundant labor (Ahmed 2001).

This district is divided into nine sub-districts; among them Bagerhat Sadar, Fakirhat,

Mollahat and Chitalmari are important for M. rosenbergii farming and the remaining are

important for tiger shrimp (Penaeus monodon) farming as a result of salt-water intrusion.

Among the four prawn farming sub-districts, Fakirhat is the most important as prawn

farming was first started in this area in the early 1970s (Mazid 1994). Fakirhat was

therefore selected for the study.

History of the blue revolution

Around 1978, a few well-off local farmers in the Bagerhat area of southwest Bangladesh

began to experiment with stocking prawn in carp ponds. These innovators experimented

with construction design, feeding, stocking and other technical aspects, and profited well

(Kendrick 1994). Some time between the late 1970s and the mid 1980s, a few pioneers

developed the first prawn cultivation in rice fields in low-lying agricultural land. The name

most frequently raised as the ‘father of freshwater prawn farming’ is Keramat Ali of the

Fakirhat area in Bagerhat district (Rutherford 1994). When the people of southwest

Bangladesh were enduring hardship, only Keramat Ali’s initiative changed the socio-

economic scenario of the whole area, and more broadly in Bangladesh, to earn a significant

amount of valuable foreign exchange through prawn farming. Keramat Ali has received

national awards for his outstanding contribution over the last 25 years.

In the late 1980s, the practice of prawn farming began to be adopted widely in the

original location of the Fakirhat area, where prawns were grown along with carp and rice

(Kamp and Brand 1994). By around 1987, a few local farmers first converted their low-

lying rice fields into gher for prawn cultivation. Since then the pace of adoption increased

dramatically as more farmers watched their neighbors profiting from prawn cultivation and

decided to begin prawn farming as well. The news soon spread to other areas, and farmers

in other parts of Bagerhat district began to adopt this new technology (Rutherford 1994).

Although it has developed strongly in other areas, the number of prawn farms and farmers

are still the highest in the Fakirhat area. There have been changes of economic activities in

the Fakirhat area due to prawn farming which have led to its being called ‘the Kuwait of

Bangladesh’ (Kendrick 1994).

The early innovators tended to be large- and medium-sized farmers, but increasing

numbers of small farmers also started prawn farming. The expansion of prawn cultivation

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Fig. 1 Map of Bangladesh showing the study area

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has been dramatic, and since 1990 adoption has accelerated, spreading to other southwest

districts (Ahmed et al. 2008). Since then, prawn farming has become one of the most

financially attractive investment opportunities and a multimillion dollar industry. In recent

years (since 2000), the increase in demand for prawn in the international market has

attracted many fish farmers to switch to prawn cultivation in different parts of Bangladesh.

Table 1 provides a summary of the historical development of prawn farming in

Bangladesh.

Data collection methods

Field research was conducted for a 12-month period, from January to December 2006.2 A

combination of the following participatory, qualitative and quantitative methods was used

for primary data collection.

Participatory rural appraisal

Participatory rural appraisal (PRA) is a group of methods to collect information in a

participatory fashion from rural communities. The advantage of PRA over other methods is

that it allows wider participation of the community, and therefore the information collected

is likely to be more accurate (Chambers 1992). For this study the PRA tools—transect walk

and focus group discussion (FGD)—were conducted with prawn farmers and associated

groups, such as fry traders, feed traders, intermediaries, prawn traders and day laborers

including women and children.

The transect walk involved developing an understanding of a village, its farming

practices and natural resources by walking the area in a straight line. The transect walk is

not passively observational; it allows researchers to discuss with villagers who accompany

on the walk (Chambers 1994). For this study, approximately 50 transect walks were carried

out through the study area along the possible roads, involving discussions with over 1,000

villagers. This method was used to get a quick picture of the prawn farming communities

in terms of the blue revolution.

FGD is a group meeting where people from the target communities discuss selected

topics. A total of 50 FGD sessions were conducted for this study where each group

consisted of 6–12 persons (total 439) and the duration of each session was approximately

Table 1 Milestones for the development of prawn farming in Bangladesh

Years Development

Early 1970s Prawn farming first started in the Bagerhat area of southwest Bangladesh

Late 1970s Began to experiment with stocking prawn in carp ponds

Early 1980s Developed prawn cultivation in low-lying agricultural land and rice fields

Late 1980s Converted low-lying rice fields into gher for prawn cultivation

Early 1990s Prawn farming started in other southwest districts: Khulna, Satkhira and Jessore

Late 1990s Prawn farming became an attractive investment opportunity for small farmers

Early 2000s Prawn farming began in Noakhali, Patuakhali and Mymensingh districts

2 Building upon detailed baseline data collected by one of the authors during 1998–1999 in the Bagerhatarea (Ahmed 2001), recent fieldwork seeks to explore impacts of the blue revolution from the perspective oflocal people.

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an hour. FGD was used to get an overview of prawn farming practices and its socio-

economic benefits. FGD sessions were held in front of village shops, under large trees, in

farmers’ houses and on market premises, wherever there were spontaneous gatherings and

where participants could sit, feel comfortable and were easily observed.

Questionnaire interviews

Questionnaire interviews with prawn farmers were preceded by preparation and testing of

the questionnaire and training of enumerators. For questionnaire interviews, farmers were

selected through stratified3 random sampling based on farm size. For this sampling method,

a database of prawn farmers including farm size was collected from the Bagerhat District

Fisheries Office. Prawn farmers were classified into three groups on the basis of farm size:

small, medium and large farmers (Table 2). Prawn farmers of each group were viewed as

the population of each stratum. Samples from each stratum were selected following simple

random sampling4 technique. A total of 180 prawn farmers, 60 in each stratum, were

interviewed at their houses and/or farm sites. The interviews, lasting about an hour,

focused on prawn farming systems, production technology, productivity, production con-

straints, prawn marketing, production costs and returns, and farmers improved conditions

including socio-economic benefits.

Cross-check interviews with key informants

A key informant is someone with special knowledge on a particular topic. Key informants

are expected to be able to answer questions about the knowledge and behavior of others, and

the operations of the broader systems (Theis and Grady 1991). Cross-check interviews were

conducted with school teachers, local leaders, District and Sub-district Fisheries Officers,

Table 2 Stratification of prawn farmers based on farm size

Farmerscategory

Farm size Samplesize

Characteristics

Small farmers Up to 0.20 ha (up to50 decimals)

60 Mainly extensive farming using lower inputs;late innovators; require loans for farm operation

Medium farmers 0.21–0.40 ha(51–100 decimals)

60 Improved extensive farming; intermediatelevel of inputs; personal assets (cows, timber,gold jewelry) depletion for prawn farming

Large farmers Above 0.40 ha(above 100decimals)

60 Semi-intensive farming using higher inputs;early innovators; built prawn farms on theirown land with their own capital

3 A stratified sample is one obtained by separating the population elements into non-overlapping groups,called strata, and then selecting a sample from each stratum (Scheaffer et al. 1990). Arens and Loebbecke(1981) noted that stratification is most commonly used for reducing the sample size needed to achieve adesired level of precision and reliability.4 A sample is drawn from a population in such a way that every possible sample has an equal chance ofbeing selected (Scheaffer et al. 1990). Schofield (1993) noted that simple random sampling is the funda-mental method of probability where ‘simple’ does not mean that it is easier to carry out than other methods,but that steps are taken to ensure that nothing influences selection each time a choice is made, other thanchance.

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researchers, policymakers, social workers, relevant non-governmental organization (NGO)

workers and project staff (e.g., the WorldFish Center, Winrock International, Danida). A

total of 29 key informants were interviewed in their offices and/or houses.

Data analysis

Data from questionnaire interviews were coded and entered into a database system using

Microsoft Excel software. The statistical package for social science (SPSS; SPSS Inc.,

Chicago, IL, USA) was used to analyze the data, producing descriptive statistics. Results

from the data analyses, in combination with qualitative information collected through

different data collection methods, were used to describe prawn farming with its impacts of

the blue revolution. Comparisons among farmers’ categories were made by ANOVA F-test

and a two-tailed P \ 0.05 indicated statistically significant differences. Economic analysis

was conducted to determine net returns of prawn farming (Shang 1990). The analysis was

based on farm-gate prices of prawn and current local market prices of all other items

expressed in US dollars (US$1 = Tk65 in December 2006).

Results and discussion

Prawn culture systems

The gher design potentially provides good opportunities for diversified IAA production,

with primary dependence on prawn, fish, rice and dike crops. Prawns are produced for

export markets while fish, rice and dike crops are for local markets and household con-

sumption (Fig. 2). The peak season of prawn farming is from May to January. Prawn fry

are stocked when they become available in May to June and are harvested primarily from

November to January, a culture period of around 9 months.

According to the survey, 92% of respondents integrated prawn, fish and rice, and only

8% cultured prawn and rice (Table 3). The highest percentage of fully integrated farms was

found for large farmers (97%), followed by medium (92%) and small (87%) farmers. There

Prawn farming in gher systems

Outputs: prawn, fish, rice and dike

crops

Domestic markets: fish,

rice, dike crops

Household consumption: fish,

rice, dike crops

Export market of prawn

Inputs: prawn fry, feed, fertilizer,

labor

Other inputs: fish fry, feed,

agricultural seed

Fig. 2 Prawn production process in gher systems (based on field survey)

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was a significant difference (P \ 0.05) in culture systems among farmer categories. In

general, farmers cultivate boro rice in the central plateau of the gher during the dry season

from January to April and aman rice during the monsoon from June to September. Prawn

culture with rice farming is ecologically sound, and rice production has increased as

prawns predate upon insects, which improves soil fertility. This practice is now growing in

Bangladesh, partly as a result of the promotion of integrated pest management (IPM).

Many Asian countries (e.g., China, Thailand and Vietnam) promote prawn culture in rice

fields as a form of IPM and it is an effective way to increase the productivity of rice and

prawn (Giap et al. 2005).

A range of carp species is cultured with the prawns. Farmers stock Indian major carps

such as catla (Catla catla), rohu (Labeo rohita), mrigal (Cirrhinus cirrhosus) and exotic

carps including silver carp (Hypophthalmichthys molitrix), grass carp (Ctenopharyngodonidella) and common carp (Cyprinus carpio). In general, farmers do not attempt to stock any

specific ratio of different carp species. The average annual stocking density was found to

be 3,514 fingerling ha-1. Although most farmers (92%) produced fish with the prawns,

only 8% did not because of low production of prawn and fish, and/or because fish compete

with prawn for feed, space and their limited capital. However, Hossain and Islam (2006)

noted that the growth and yield of prawn in integrated farming systems do not appear to be

influenced by fish, and therefore prawn cum fish culture is technically and economically

viable.

Almost all farmers cultivate a variety of dike crops on a small scale. During the winter

season, different types of dike crops such as carrot, tomato, onion, mustard, long yard bean,

spinach and pea are produced, while ladies finger (okra), sweet gourd and other vegetables

are produced in the summer season. Fruits such as banana, guava and papaya are also

grown on dikes. The number of crops grown is the major determinant of profitability from

dike cropping. According to the survey, most of the large farmers produced more than six

crops in the different seasons, while medium and small farmers produced 4–6 and 1–3

crops, respectively.

Farming practices

Prawn culture still remains dependent on wild fry as production of hatchery is limited and

farmers consider them to be of lower quality. In addition, the survival of wild fry is

reported to be much higher than that of hatchery produced fry. Although there are 81

prawn hatcheries in Bangladesh, only 38 (47%) are operational in the sense of producing

around 100 million fry annually, 20% of total demand (Ahmed 2008). Lack of technical

knowledge, inadequate skilled manpower and insufficient supply of wild brood are

important reasons for the poor results of many hatcheries. The average annual stocking

Table 3 Integrated prawn culture systems by category of farmers

Culture system Farmer categories

Small Medium Large All farmersn = 60 n = 60 n = 60 n = 180

Prawn–fish–rice 52 (87%) 55 (92%) 58 (97%) 165 (92%)

Prawn–rice 8 (13%) 5 (8%) 2 (3%) 15 (8%)

n sample size of prawn farmers

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density of wild postlarvae was found to be 21,519 ha-1 (Table 4). There was a significant

difference (P \ 0.05) in stocking rates among farmer categories.

A variety of feeds are used for prawn farming but the preferred feed is the freshwater

snail (Pila globosa). In general, chopped snail meat is given twice a day in the morning and

evening. According to the survey, an average 9,913 kg ha-1 year-1 of snail meat was

applied for prawn farming (Table 4). The supply of snail is not regular and therefore

farmers also use industrially manufactured pelleted feeds or homemade feed prepared by

mixing cooked rice, rice bran, oil cake and fishmeal. In addition to snail meat, the average

annual feeding rate was 3,507 kg ha-1. There was a significant difference (P \ 0.05) in

feeding rates among farmer categories.

For grow-out of prawn, farmers use fertilizers mainly including cow dung, urea and

triple super phosphate (TSP) at varying frequencies. On average, annual fertilization rates

were 1,439 kg ha-1 of cow dung, 435 kg ha-1 of urea and 223 kg ha-1 of TSP. Although

all large and medium farmers used fertilizers, 65% of small farmers did not use inorganic

fertilizers due to lack of money and poor knowledge of prawn farming. Small farmers

mainly used cow dung, which is relatively cheap and abundant in the study area.

Table 4 Inputs and outputs of integrated prawn farming by farmer category in 2006

Inputs and outputs Farmer categories

Small Medium Large All farmers

Inputs

Stocking (quantity ha-1 year-1)

Prawn fry 17,753 ± 2,469 21,268 ± 3,705 25,527 ± 4,547 21,519 ± 3,561

Fish fingerling 2,109 ± 346 3,487 ± 523 4,954 ± 717 3,514 ± 532

Feeding (kg ha-1 year-1)

Snail meat 7,932 ± 1,102 9,416 ± 1,743 12,383 ± 1,988 9,913 ± 1,634

Other feed 2,818 ± 561 3,472 ± 713 4,239 ± 946 3,507 ± 739

Fertilization (kg ha-1 year-1)

Cow dung 1,459 ± 227 1,372 ± 186 1,481 ± 211 1,439 ± 209

Urea 312 ± 45 461 ± 76 527 ± 89 435 ± 73

TSP 167 ± 31 224 ± 47 283 ± 65 223 ± 45

Outputs (kg ha-1 year-1)

Prawn 387 ± 52 451 ± 76 564 ± 83 467 ± 73

Fish 703 ± 81 992 ± 103 1,271 ± 197 986 ± 131

Rice 2,106 ± 383 2,265 ± 412 2,396 ± 427 2,257 ± 409

Values given as mean ± standard deviation (SD)

Table 5 Comparison of prawnyields in Bangladesh and otherAsian countries

Country Prawn production(kg ha-1 year-1)

Reference

Bangladesh 467 This study

China 1,500 Weimin and Xianping (2002)

India 600–1,000 Raizada et al. (2005)

Thailand 2,338 Vicki (2007)

Vietnam 1,000–1,500 New (2005)

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Productivity

According to the survey, the average annual yield of prawn, fish and rice was estimated at

467, 986 and 2,257 kg ha-1, respectively (Table 4). There was a significant difference

(P \ 0.05) in yields among farmer categories, because of the differences of farm size, feed

and seed inputs, and management skills. Results showed that large farmers produced higher

production due to more inputs, larger farm size and longer experience of prawn farming than

others. Nevertheless, most of the prawns are cultivated using extensive methods, and pro-

ductivity is low compared to other countries (Table 5). Countries with a larger export

market than Bangladesh use more intensive techniques and have significantly higher yields.

Total rice production has probably decreased as a result of widespread conversion of

rice fields to prawn farms. However, at the farm level, many farmers (18%) reported

increased rice production as higher dikes keep fully saline water out of their fields. Pro-

ductivity of rice was estimated including the area of canal and water for prawn farming,

and thus actual yield would typically be higher by 20–25%. In general, more than 50% of

the gher area is allocated for rice cultivation (Nandeesha 2003).

Production constraints

A number of constraints were reported by respondents for prawn farming, including water

pollution, diseases, natural disasters (flood, drought) and high production costs. According

to the survey, 58% of respondents identified high production costs as their single most

important constraint (Table 6). Costs of prawn cultivation were reported to have increased

significantly in recent years as a result of increased fry, feed and labor costs. The prices of

both prawn fry and feed have increased dramatically since prawn farming has become

widespread. Inadequate finance can therefore be a significant constraint. The proportion of

respondents identifying inadequate supply of prawn fry was 24%. Only 11% and 7% of

farmers reported flood and disease to be the most important constraint, respectively. There

was a significant difference (P \ 0.05) in production constraints among farmer categories.

Marketing of prawns

The peak season of prawn marketing is from November to January. Farmers harvest their

prawns by using cast nets and seine nets. Harvested prawns are kept in aluminum or plastic

containers. The prawns are cleaned with tube-well water and kept in containers until they

are sold. Farmers grade all head-on prawns by size and weight, and sell them to the traders.

Table 6 Constraints of prawn farming by category of respondents

Key constraint Farmer categories

Small Medium Large All farmersn = 60 n = 60 n = 60 n = 180

High production costs 41 (68%) 36 (60%) 28 (47%) 105 (58%)

Low supply of prawn fry 10 (17%) 15 (25%) 19 (32%) 44 (24%)

Flood 5 (8%) 6 (10%) 8 (13%) 19 (11%)

Disease 4 (7%) 3 (5%) 5 (8%) 12 (7%)

n sample size of prawn farmers

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The price of prawns depends on grade, quality, seasonality, supply and demand. The

average farm-gate prices of prawns varied from US$2.61 to $6.55 kg-1 (Table 7).

The market chain from farmers to the international market passes through a number of

intermediaries (Fig. 3). Farmers commonly use vans and rickshaws (i.e., pedal tricycle) to

transport the prawns to local markets. Sometimes field workers, locally known as foria,

buy prawns from the farmers at the farm side and carrying them to the traders. Prawn

traders are normally based in local markets near prawn farming areas. They supply prawns

directly, or via agents, to the processing plants within 1 or 2 days of purchase, during

which time they are kept on ice. Consignments are sent once sufficient quantities (200–

250 kg trader-1) have been obtained. Trucks and pickups are used to transport prawns to

the processors. Finally, processing plants export frozen headless prawns either as indi-

vidually quick frozen or block frozen to the international market through Mongla port in

southwest Bangladesh. Prawn marketing is not very competitive but plays a vital role in

connecting the farmers and foreign consumers, thus contributing significantly in the value-

adding process and consequently in earning of foreign currency.

About 35 plants are involved in prawn processing and export in southwest Bangladesh

(Muir 2003). Most processing plants are broadly compliant with hazard analysis and

critical control point (HACCP) requirements. In recent years, the Department of Fisheries

in Bangladesh has amended the prawn inspection and quality control act to incorporate

HACCP principles. Nevertheless, Bangladesh has been facing problems in maintaining

quality standards in prawn processing. Although prawn markets have grown strongly in

volume over the last two decades, concerns over processing standards have left Bangladesh

in a relatively weak position. The issue of risk associated with the export of contaminated

Table 7 Grade and averagefarm-gate prices of head-onprawns in 2006

Grade Number of head-onprawns per kg

Averageweight ofprawn (g)

Marketshare(%)

Average price(US$ per kg)

5 5 or less 200 2 6.55

10 6–10 125 8 5.39

20 11–20 70 50 4.37

30 21–30 40 25 3.64

50 31–50 25 15 2.61

2%

90%

10%

18%

80% Prawnfarmers

Prawntraders

Ship at Mongla port

Processingplants

International markets

Fieldworkers

Agents

Fig. 3 Freshwater prawn supply chain from farmers to international markets (based on survey)

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product cannot be underestimated (Ahmed et al. 2007a). If the export of prawns were to be

increased, the product needs to be carefully marketed. A good reputation for quality will

need to be established and maintained from an international market perspective.

Economics of prawn farming

Table 8 shows that the average annual production costs of integrated prawn farming

(excluding dike cropping) for all sample farmers averaged US$2,218 ha-1, varying from

US$1,893 ha-1 in small farms to US$2,219 ha-1 in medium and US$2,563 ha-1 in large

farms. There was a significant difference (P \ 0.05) in production costs among farm size.

Regardless of farm category, the average annual variable and fixed costs were estimated at

US$1,783 ha-1 (80% of total costs) and US$435 ha-1 (20%), respectively. Among the

variable costs, seed and feed dominated all other costs representing about 32 and 28%

of total costs, respectively. Under fixed costs, the average annual depreciation costs

Table 8 Average production costs and returns (US$ ha-1 year-1) of integrated prawn farming by farmers’category in 2006

Costs and returns Farmer categories All farmers

Small Medium Large

Variable costs (VC)

Seed (prawn and fish) 578 (31%) 708 (32%) 861 (34%) 713 (32%)

Feed 506 (27%) 619 (28%) 731 (29%) 618 (28%)

Fertilizer 52 (3%) 69 (3%) 83 (3%) 67 (3%)

Labor (family and hired) 153 (8%) 178 (8%) 189 (7%) 173 (8%)

Harvesting and marketing 44 (2%) 51 (2%) 56 (2%) 49 (2%)

Rice cultivation 122 (6%) 137 (6%) 141 (5%) 133 (6%)

Miscellaneous 26 (1%) 31 (2%) 35 (2%) 30 (1%)

Sub-total 1,481 (78%) 1,793 (81%) 2,096 (82%) 1,783 (80%)

Fixed costs (FC)

Depreciationa 106 (6%) 113 (5%) 124 (5%) 115 (5%)

Interestb 139 (7%) 151 (7%) 168 (6%) 153 (7%)

Land use costc 167 (9%) 162 (7%) 175 (7%) 167 (8%)

Sub-total 412 (22%) 426 (19%) 467 (18%) 435 (20%)

Total costs (TC = VC ? FC) 1,893 (100%) 2,219 (100%) 2,563 (100%) 2,218 (100%)

Gross revenue (GR)d

Prawn 2,232 (67%) 2,601 (65%) 3,253 (65%) 2,694 (66%)

Fish 757 (23%) 1,068 (26%) 1,368 (27%) 1,061 (26%)

Rice 324 (10%) 348 (9%) 368 (8%) 347 (8%)

Total 3,313 (100%) 4,017 (100%) 4,989 (100%) 4,102 (100%)

Net return (NR = GR-TC) 1,420 1,798 2,426 1,884

Parentheses indicate as a percent of totala [(purchase price-salvage value)/economic life]b Interest on operating capital or loan was charged at the rate of 15% per annumc Valuation of land at its rental price or lease moneyd Production 9 farm-gate price

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(i.e., water pump, net, other equipment), interest on operating capital and land use costs or

lease money were estimated at US$115, US$153 and US$167 ha-1, respectively.

The average annual gross revenue was calculated at US$4,102 ha-1, varying from

US$3,313 ha-1 in small farms to US$4,017 ha-1 in medium and US$4,989 ha-1 in large

farms (Table 8). The highest average gross revenue was reported by large farmers due to

higher production, whilst the lowest was found for small farmers due to lower production.

There were striking differences of gross revenues among prawn (66%), fish (26%) and rice

(8%) production. Despite higher production costs per hectare, the average annual net return

was higher in large farms (US$2,426), compared with medium (US$1,798) and small

(US$1,420) farms. There was a significant difference (P \ 0.05) in net returns among farm

categories.

Impacts of the blue revolution

Overall, the impacts of the blue revolution appear to have had a positive effect, and

certainly most members of the prawn farming community confirm this. The changes

brought about by the cultivation of prawn have been profound. The following paragraphs

address impacts of the blue revolution.

Prawn farming: a cash economy

The switch from rice fields to prawn farms is not merely a change in cropping system,

more importantly it is a shift from production of a staple food crop to a commodity for the

international market. Because it is an export product, prawn production infused unprece-

dented amounts of cash into the local economy. Much of this capital circulates through the

local economy and beyond prawn farming communities. Most farmers have improved their

income through increased profitability in prawn farming and diversified cropping systems.

Clearly there have been visible qualitative and quantitative changes in level of economic

activity. During prawn marketing season, farmers and associated groups have abundant

cash in their hands to buy foods, clothes and basic items. A significant number of small

markets have been established in prawn farming communities including tea stalls and

restaurants, as well as small shops, fruit and vegetable sellers.

Across the study, the average annual net income from integrated prawn farming was

estimated at US$776 farmer-1, varying from US$476 for small farmers to US$719 for

medium and US$1,132 for large farmers. There was a significant difference (P \ 0.05) in

income among farmer categories. The average annual income was found to increase with

increased farm size. The farm size was significantly and positively related to the farmers’

income; the value of coefficient correlation was 0.84, which was significant at the 0.001 level.

It seems certain that the rich are getting richer as a result of prawn farming. Results showed

that large farmers made a good profit, and medium farmers made an adequate profit. How-

ever, small farmers had benefited the least. In contrast, a few key informants stated that small

farmers had benefited the most, because their situation had been desperate before prawn

farming as they were dependent on daily wage labor, and now they are living a better

existence. Income from prawn production offers many small farmers the opportunity to

engage in petty business, poultry farming and livestock rearing to supplement their income.

Income also provides the opportunity to increase security for coping with uncertain situa-

tions, such as illness and natural disasters (i.e., floods, heavy rain and cyclones).

A number of negative social impacts were found due to increased farmer income. For

example, dowry payment has increased as a result of prawn farming. Families of

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bridegrooms that formerly would have received a bicycle from the bride’s family are now

demanding a motorcycle, large amounts of cash money, gold jewelry and wristwatches.

Risks of theft and robbery have increased due to increased amounts of cash transactions.

Sometimes jealous people throw poison into prawn farms at night, after which all the

prawns may die.

Food security

The second most significant change was in food consumption. Before prawn farming a

large number of farmers lived below the poverty line, and after converting their rice fields

to prawn farms, they have increased their food consumption. Survey results showed that

the integrated prawn production systems have substantially improved their food security.5

Almost all small farmers reported that before prawn farming they took food twice a day.

As a result of prawn farming, they are able to eat rice three times a day and also eat better

quality food, including fish, meat, milk, eggs, fruits and vegetables. Vegetables are now

more abundant and are also cheaper as a result of dike cropping, and farmers have ben-

efited from selling these.

The consumption of fish in the households of prawn farmers and other community

members has increased notably over recent years as fish are now abundant and cheaper due

to integrated prawn–fish–rice farming. It was found that households of farmers tend to eat

small fish rather than sell them. In addition to animal protein, small fish is a valuable source

of micronutrients, vitamins and minerals. These are eaten whole with bones and heads, thus

contributing calcium, phosphorus, iron, zinc and vitamins to the diets of poor families. Small

fish also have particular importance for the diets of children and lactating mothers to avoid

child blindness and reduce infant mortality (Roos et al. 2007). Prawn heads and legs are also

a supplemental protein source that practically the whole community enjoys during the prawn

exporting season after beheading; farmers never eat the prawns themselves.

Although food security has been increased, it may be an important issue for small

farmers who turned good rice fields to prawn farms. Farmers who converted good rice

fields reported that they felt greater food insecurity due to lower rice production. A few

small farmers (5%) reported that after converting all of their rice fields to prawn farms at

once, their prawn harvest failed due to floods and it became hard to feed their large

families. Sharecropping opportunities have also been reduced dramatically as a result of

prawn farming. Rich farmers who would previously have given their surplus land out for

sharecropping now prefer to lease out for prawn farming. As a result of reduced share-

cropping opportunities, some households faced food insecurity.

Social status

Freshwater prawn production has been accompanied by a great deal of social benefits, and

these benefits depend on resource ownership. Evidence has suggested that the positive

impact of prawn farming is higher among those farmers who have large farms. According

to the survey, all large farmers (100%) benefited the most and improved their social status,

while 95% of medium farmers also improved their socio-economic conditions. Most small

farmers (88%) also increased their social status, but 12% reported that conditions were

5 Food security defined by the FAO (2006) as a condition when people at all times have physical andeconomic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences foran active and healthy life.

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unchanged or diminished. These less successful farmers explained that due to lack of

technical knowledge, higher production costs, flood, diseases of prawns, theft and poisoned

gher had failed their prawn harvest, which were the principal reasons for their disadvan-

taged situation.

Most small farmers reported that risks and debt were not new to them after entering into

prawn cultivation by taking loans. The poor farmers generally took loans from money-

lenders with high interest rates at 10% monthly (i.e., 120% yearly). In general, rich farmers

and local businessmen act as moneylenders. Farmers often used their principal asset, land,

as collateral. The numbers of farmers who defaulted on their loans and lost land have

increased during the last few years. According to key informants, losing land to money-

lenders occurred when farmers were previously very poor and relatively powerless.

A few disadvantaged farmers described that the first year of prawn farming was the

period of greatest insecurity, because assets such as cows, gold jewelry and timber were

sold, loans taken out, and rice crops foregone. As a result, many of them actually became

poorer, or at least potentially more vulnerable. The study also found that leased farmers

have become disadvantaged. The costs of leases had increased significantly due to

increased demand from the greater number of people wishing to participate in prawn

farming. Returns had also decreased as the costs of prawn farming had increased signifi-

cantly. However, a few key informants suggested that most landless people and poor

farmers had benefited through prawn farming by leasing a prawn farm.

Some small farmers (10%) experienced dramatic improvement in their living standards

because they converted low-lying lands into prawn farms which were previously not

utilized. A few small farmers (12%) had managed to avoid high-interest loans, and

increased cash income has provided the opportunity for more investment in productive

resources. For these farmers prawn production has obviously brought positive impacts.

Poor people are also able to profit by selling land as land prices have skyrocketed since the

start of prawn farming. In some cases, rich farmers and wealthy people forced poor farmers

to sell their land. Friction between the two sides sometimes led to scuffles involving

villagers and hired enforcers employed by the wealthy. Some of the minority Hindu people

feel insecure due to conflict with Muslims, and a number have migrated to India, selling

their land and prawn farms to others.

In spite of social constraints, the great majority of respondents (94%) have improved their

social status through prawn farming. Farmers’ improved conditions can be described on the

basis of qualitative indicators, such as standards of living, purchasing power, choice and

ability as an economic sector. Most farmers have improved their housing condition as profits

from prawn farming are used to replace bamboo roofs and walls with tin sheets and wood.

There have also been an increased number of boats, bicycles and motorcycles for transport.

Farmers have also improved their health and sanitary facilities as well as their drinking water

supplies through tube-wells. The number of recreational items, such as radios, televisions,

and mobile phones for communications (i.e., prawn marketing) has also increased. The

acquisition of such goods can be used as an indirect measure of wealth and is also attributed

to more modern developing conditions. Most farmers with recreational items noted that they

were interested in listening to folk-songs and news, particularly since newspapers were not

available and many could not read them anyway due to lack of education.

Livelihood of the poor

Prawn farming brought about dramatic improvements in the livelihood of the poor. A range

of associated groups such as wild fry collectors, fry traders, snail harvesters, snail traders,

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feed traders, intermediaries, prawn traders, transporters and day laborers including women

and children have benefited. Prawn fry collectors are the most marginalized people in

coastal communities and fishing prawn fry is an alternative livelihood coping strategy,

offering a substantial part of their income. A network for fry trading, such as the wild fry

collectors, suppliers, traders and agents all gain from this system. Overall, the supply of

snails has also generated a number of employment opportunities in catching, processing,

transport and marketing activities. A similar network for prawn marketing has also been

established.

The poorest and landless households have also benefited from prawn farming due to

greater employment opportunities. The opportunities for day laborers to find work have

increased significantly for prawn farming and marketing activities. Labor is required for

construction of prawn farms, night guards, fry trading, snail breaking, feed trading, prawn

harvesting and marketing. In prawn markets, laborers perform post-harvest tasks that

include handling, cleaning, sorting, grading and icing. They also work to carry ice from the

ice factories, break it up, mix ice with prawns and load prawns onto the vehicles. Addi-

tional employment opportunities are also generated in prawn hatcheries, commercial prawn

feed industries and in the transport sector, from rickshaws and vans to large motorized

vehicles, which carry prawns to processing plants. A large number of contract workers are

also involved in prawn processing plants. Although wage rates fluctuate during the year

with seasonal labor demand, wages in prawn farming areas (US$1.65 day-1) appear to be

higher than agricultural wage rates in nearby rice producing areas. Most day laborers

reported experiencing real benefits from the higher wages and increased wage-earning

opportunities brought about by prawn farming, suggesting active involvement over

300 days in a year. Almost all day laborers noted that they were better off now than they

were before prawn farming became widespread.

Women’s empowerment

Rural society in Bangladesh is still characterized by traditional value systems, in which the

position of men is held to be superior to that of women (Morris 1997; Ahmed 2005). There

have, however, been recent changes in the attitude of the people towards the role of women

in various aspects of household decision-making and income generating activities (King

1989; Gupta 1990), and a number of activities associated with prawn farming increasingly

involve women. Women are involved in various facets of prawn cultivation, including

feeding of prawns, farm supervision and management, dike cropping, prawn harvesting and

post-harvest handling. In dike cropping, they involve mainly sowing crops, planting sap-

lings, fertilization, weeding, irrigation, harvesting and marketing. Women also assist in

prawn marketing, especially where emergency harvests are required due to the threat of

flood or other reasons (theft, poisoning). After harvesting, women are also involved in

sorting, grading and weighing of prawns. In previous years, women were exclusively

engaged in beheading prawns at their home premises, but recently that has shifted to take

place in processing plants as per the suggestion of importing countries.

Job opportunities for landless women have also increased since prawn farming started.

A few key informants noted that the migration of women has reduced due to economic

changes brought about by prawn farming. In the past, poor women had to migrate to town

seeking jobs, but more recently they have returned to find work as wage laborers in prawn

farming activities. A large number of women are employed in processing plants to clean

and behead prawns, as well as for freezing and packaging. Women are also involved in

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snail harvesting, breaking and marketing as wage laborers. A few women are involved in

the weaving of nets for prawn harvesting, and this has increased their earnings.

Prawn farming activities of women at the village level have enhanced their position in

families and societies. Their prawn-related cash income has given them some economic

independence. They now tend to play a stronger role in economic decisions for the

management of their households, including those concerning education of children,

attending social functions, inviting guests, accepting family planning methods, attending

religious functions, and advising sons and daughters on selection of spouses.

Environmental impacts

Considerable debate and arguments occurred during the last decade on various impacts of

prawn and shrimp farming on the environment, biodiversity and society (Hossain 2001;

Islam 2003). Nevertheless, prawn farming in Bangladesh had not been associated with any

of the negative environmental consequences for which shrimp production has received so

much criticism (Ahmed 2001). However, in recent years there have been some concerns

about the long-term environmental sustainability of prawn farming. The major changes in

the environment that have been found include problems with prawn farm construction,

wild fry fishing and snail harvesting for use as prawn feed.

Large areas of rice fields have been used for construction of prawn farms. The reduction

in rice fields is likely to have negative impacts on rice production, and decreased rice

production has meant decreased availability of paddy straw, which is used for both cooking

fuel and fodder for cattle. The reduction of rice fields negatively affected the population of

the Indian bullfrog (Rana tigrina), which plays an important role in rice farming systems

by consuming insects to increase rice production (Nuruzzaman 1993).

Environmental impacts associated with prawn postlarvae fishing are likely to occur due

to significant by-catch (Ahmed 2003; EJF 2004). By-catch rates are high as prawn fry are

typically harvested using very fine mesh nets that are indiscriminate, catching most aquatic

organisms in their path. A huge number of fish fry are caught and discarded, and with

unknown mortality effects, may have severe long-term impacts on coastal fisheries. Wild

prawn production has also significantly decreased due to uncontrolled fishing of prawn fry.

Negative environmental impacts also appear from over-harvesting of snails. The snail

population has become extinct in most parts of prawn farming areas due to excessive

harvesting during the monsoon season, which is the peak season of their reproduction

(Ahmed et al. 1997). Removal of the snail is likely to result in an increase in the growth of

at least some species of aquatic weeds which could reduce light penetration as well as

photosynthesis and could lead to eutrophication of water bodies (Gain 1998). Snail har-

vesting has created the problem of disposal of large quantities of snail shells, which has

resulted in pollution and blockage of canals where they are often dumped.

Conclusions

Freshwater prawn farming plays an important role in the economy of Bangladesh, earning

valuable foreign exchange, contributing to increased food production, diversifying the

economy and increasing employment opportunities. The evidence presented in this study

confirms that the blue revolution of prawn farming has brought about widespread social

and economic benefits in southwest Bangladesh. Most farmers have improved their income

through integrated prawn farming and the combination of prawn, fish and rice production

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give particularly good potential returns. Socio-economic conditions have altered and most

farmers have improved their status through prawn farming. The blue revolution has

increased food security, purchasing power, choice and ability as an economic sector for

most farmers.

While there is great potential for increasing family income through engaging in prawn

cultivation, a number of factors contribute to the vulnerability of poor farmers including

high production costs, inadequate supply of prawn fry, flooding and diseases of prawns. In

addition, farmers are not achieving a high level of productivity compared to other countries

due to a variety of technical constraints. It is therefore necessary to provide technical

assistance to the farmers for sustainable prawn farming. Training and extension services

would also help to improve production and reduce risks. It may also be necessary to

promote low-cost technologies for higher production (Pillay 1994).

The present reliance on wild-caught prawn fry and snails as prawn feed puts pressure on

the local environment. It is therefore necessary to explore the possibility of developing

prawn hatcheries and processed feed industries. Development of prawn hatcheries and feed

production systems using low-cost locally produced ingredients would help to increase

farmers’ profit margins, reduce the negative environmental impacts and increase job

opportunities. Hatcheries may reduce the pressure on wild fry exploitation and increase

wild production (Ahmed 2008).

The provision of low-interest credit would also help to reduce the risks for small and

marginal farmers. Access to credit at reasonable interest rates and with appropriate

repayment schedules will be essential if prawn farming is to become accessible to the

poorer farmers. Thus, the government as well as national banks should provide adequate

access to interest-free credit or credit at very low interest rates.

Although various constraints can be recognized, the prospects for prawn farming in rice

fields are positive. However, a number of significant challenges, particularly social and

environmental issues, will need to be overcome to translate its benefits effectively to the

thousands of rural poor. The issues of environmental sustainability of freshwater prawn

cultivation, while clearly not as negative as those of marine shrimp culture in Bangladesh,

are nevertheless poorly understood. Therefore, research would be required to understand

and quantify environmental impacts for sustainable prawn farming.

Acknowledgments The study was supported by the UK Department for International Development(DFID) as part of the Aquaculture and Fish Genetics Research Program (AFGRP). The opinions expressedherein are those of the authors and do not necessarily reflect the views of DFID or AFGRP.

References

Ahmed N (2001) Socio-economic aspects of freshwater prawn culture development in Bangladesh. PhDThesis. Institute of Aquaculture, University of Stirling, Scotland, p 320

Ahmed N (2003) Environmental impacts of freshwater prawn farming in Bangladesh. Shellfish News 15:25–28Ahmed N (2005) The role of women in freshwater prawn farming in southwest Bangladesh. Fish Farmer

28(2):14–16Ahmed N (2008) Freshwater prawn hatcheries in Bangladesh: concern of Broodstock. Aquac Asia 13(3):22–26Ahmed N, Miah MI, Islam MA (1997) Reproductive biology of freshwater snail Pila globosa (Swainson).

Progress Agric 8:225–229Ahmed N, Ahammed F, Lecouffe C (2007a) Socio-economic aspects of small-scale freshwater prawn

marketing systems in Mymensingh, Bangladesh. Aquac Econ Manag 11:335–353Ahmed N, Wahab MA, Thilsted SH (2007b) Integrated aquaculture–agriculture systems in Bangladesh:

potential for sustainable livelihoods and nutritional security of the rural poor. Aquac Asia 12(1):14–22

572 Aquacult Int (2010) 18:555–574

123

Ahmed N, Demaine H, Muir JF (2008) Freshwater prawn farming in Bangladesh: history, present status andfuture prospects. Aquacult Res 39:806–819

Arens AA, Loebbecke JK (1981) Applications of statistical sampling to auditing. Prentice Hall Inc.,Englewood Cliffs, NJ

Bailey C (1985) The blue revolution: the impact of technological innovation on third world fisheries. RuralSociol 5:259–266

Chambers R (1992) Rural appraisal: rapid, relaxed and participatory. IDS Discussion Paper 311. Interna-tional Development Studies, Brighton, UK

Chambers R (1994) The origins and practice of participatory rural appraisal. World Dev 22:953–969Cunningham WP, Saigo BW, Cunningham MA (2004) Environmental science: a global concern. McGraw-

Hill Higher Education, New YorkDepartment of Fisheries (DOF) (2007) Fishery statistical yearbook of Bangladesh 2005–2006. Fisheries

Resources Survey System. Department of Fisheries, Ministry of Fisheries and Livestock, DhakaEdwards P (1998) A systems approach for the promotion of integrated aquaculture. Aquac Econ Manag

2:1–12Environmental Justice Foundation (EJF) (2004) Desert in the delta: a report on the environmental, human

rights and social impacts of shrimp production in Bangladesh. Environmental Justice Foundation,London, pp 1–13

Food Agriculture Organization (FAO) (2006) State of world aquaculture 2006. FAO Fisheries TechnicalPaper 500, Rome

Gain P (1998) Chanda beel: shrimp attacks snails and environment. Earth Touch 4:24–25Giap DH, Yi Y, Lin CK (2005) Effects of different fertilization and feeding regimes on the production of

integrated farming of rice and prawn Macrobrachium rosenbergii (De Man). Aquacult Res 36:292–299Goldburg RJ, Elliott MS, Naylor RL (2001) Marine aquaculture in the United States: environmental impacts

and policy options. Pew Oceans Commission, ArlingtonGupta MV (1990) Rural women in aquaculture: Bangladesh. Naga. ICLARM Q 13(3):8Hossain MS (2001) Biological aspects of the coastal and marine environment of Bangladesh. Ocean Coast

Manag 44:261–282Hossain MA, Islam MS (2006) Optimization of stocking density of freshwater prawn Macrobrachium

rosenbergii (de Man) in carp polyculture in Bangladesh. Aquacult Res 37:994–1000Islam MS (2003) Perspectives of the coastal and marine fisheries of the Bay of Bengal, Bangladesh. Ocean

Coast Manag 46:763–796Islam MS (2007) From pond to plate: towards a twin-driven commodity chain in Bangladesh shrimp

aquaculture. Food Policy 33:209–223Ito S (2004) Globalization and agrarian change: a case of freshwater prawn farming in Bangladesh. J Int Dev

16:1003–1013Kamp K, Brand E (1994) Greater options for local development through aquaculture (GOLDA). CARE

GOLDA Project, DhakaKendrick A (1994) The gher revolution: the social impacts of technological change in freshwater prawn

cultivation in southern Bangladesh. Bangladesh Aquaculture and Fisheries Resource Unit, DhakaKing H (1989) Fisheries development programs and women. Naga ICLARM Q 12(2):6–7Lightfoot C, Bimbao MP, Dalsgaard JPT, Pullin RSV (1993) Aquaculture and sustainability through inte-

grated resources management. Outlook Agric 22:143–150Mazid MA (1994) Evaluation of prawn farming on socio-economic aspect. Fisheries Research Institute,

MymensinghMcGinn AP (1998) Blue revolution: the promises and pitfalls of fish farming. World Watch March/

April:10–19Morris J (1997) The changing face of women in Bangladesh. Department of International and Public Affairs,

Columbia University, New YorkMovik S, Mehta L, Mtisi S, Nicol A (2005) A blue revolution for African agriculture? Int Dev Stud Bull

36(2):41–45Muir JF (2003) The future for fisheries: economic performance. Fisheries Sector Review and Future

Development Study. Commissioned with the association of the World Bank, DANIDA, USAID, FAO,DFID with the cooperation of the Bangladesh Ministry of Fisheries and Livestock and the Departmentof Fisheries, Dhaka

Nandeesha MC (2003) The gher revolution: innovations in freshwater prawn farming by Bangladeshfarmers. Aquac Asia 8(4):30–36

New MB (2005) Freshwater prawn farming: global status, recent research and a glance at the future.Aquacult Res 36:210–230

Aquacult Int (2010) 18:555–574 573

123

Nhan DK, Phong LT, Verdegem MJC, Duong LT, Bosma RH, Little DC (2007) Integrated freshwateraquaculture, crop and livestock production in the Mekong delta, Vietnam: determinants and the role ofthe pond. Agric Syst 94:445–458

Nuruzzaman AKM (1993) Coastal environment and shrimp cultivation. Bangladesh Agricultural ResearchCouncil, Dhaka

Pillay TVR (1994) Aquaculture development: progress and prospects. Fishing News Books, OxfordPrein M (2002) Integration of aquaculture into crop-animal systems in Asia. Agric Syst 71:127–146Raizada S, Chadha NK, Javed H, Ali M, Singh IJ, Kumar S, Kumar A (2005) Monoculture of giant

freshwater prawn, Macrobrachium rosenbergii in inland saline ecosystem. J Aquac Trop 20:45–56Roos N, Wahab MA, Chamnan C, Thilsted SH (2007) The role of fish in food-based strategies to combat

vitamin A and mineral deficiencies in developing countries. J Nutr 137:1106–1109Rutherford S (1994) An investigation of how freshwater prawn cultivation is financed. Bangladesh Aqua-

culture and Fisheries Resource Unit, DhakaScheaffer RL, Mendenhall W, Ott L (1990) Elementary survey sampling. PWS-KENT Publishing Company,

BostonSchofield W (1993) Principles of social and educational research. The Open University, Walton HallShang YC (1990) Aquaculture economics analysis: an introduction. Advances in world aquaculture. The

World Aquaculture society. Louisiana State University, Baten RougeThe United States Agency for International Development (USAID) (2006) A pro-poor analysis of the shrimp

sector in Bangladesh. Development and Training Services, Arlington, pp 8–89Theis J, Grady HM (1991) Participatory rapid appraisal for community development, a training manual

based on experiences in the Middle East and North Africa. International Institute for Environment andDevelopment, and Save the Children Federation, London

Vicki SS (2007) Social, economic and production characteristics of freshwater prawn Macrobrachiumrosenbergii culture in Thailand. MS Thesis. School of Natural Resources and Environment, Universityof Michigan, USA, p 47

Weimin M, Xianping G (2002) Freshwater prawn culture in China: an overview. Aquac Asia 7(1):7–12Wollenweber B, Porter JR, Lubberstedt T (2005) Need for multidisciplinary research towards a second

green revolution. Curr Opin Plant Biol 8:337–341

574 Aquacult Int (2010) 18:555–574

123