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-FfHJ Socio-economic impacts of shrimp culture - CDCA



Aquaculture Research, 1997, 28, 815-827

Socio-economic                                      impacts                    of shrimp                 culture

J H Primavera

South-east        Asian    Fisheries      Development   Centre.   Iloilo.     Philippine

Correspondence:           Dr J Honculada Primavera. Aquaculture             Department. South-east Asian Fisheries Development Centre. Tigbauan.
Iloilo. Philippines 5021 (Fax: + 6333            335 1008; E-mail;

                                                                                           production has risen from a mere 6% in 1970 to 26%
                                                                                           in 1990 (FAO 1993). Shrimp farming constitutes one
Farmed shrimp contributed 27%                           of total world                     of the phenomenal commercial success stories of the
shrimp production in 1995 with                            a volume of                      last two decades, with annual growth rates of 20-
712 000 tonnes. Undoubtedly, the                        shrimp culture                     30% in contrast to astable 2-3% increase for wild
industry earns valuable foreign                          exchange for                      catches from the ~ame period (Primavera 1994).
developing countries and generates                      jobs across the                       Shrimp (belonging to the family Penaeidae) thrive
industry from fry gatherers to                            growers and                      in the tropics and subtropics where the waters
processors.   However,    grave                         socio-economic                     are warm, and they are exported to Japan, North
consequences -including conversion, expropriation                                          America and Europe where consumer demand is
and privatization of mangroves and other lands;                                            high. In 1992, 982000 t of fanned crustaceans
salinization of water and soil; decline in food security;                                  (90% marine shrimp) valued at US$ 6.6 billion
marginalization of coastal communities, unemploy-                                          constituted only 9% of total aquaculture volume
ment and urban migration; and social conflicts -                                           but contributed 24% of total value (FAO 1995).
have followed in the wake of. shrimp farm                                                  High profitability and generation of foreign exchange
development in the Philippines and other tropical                                          have provided the major driving force in the global
countries.                                                                                 expansion of shrimp culture, attracting           both
   The paper focuses on mangrove ecosystems: the                                           national governments and international develop-
valuation and cost-benefit analysis of their goods                                         ment agencies. The key factor in the growth of
and services, and the mangrove-offshore fisheries                                          the Asian shrimp industry has been private sector
connection. Research, gaps in these areas and the                                          initiative including the involvement of multinational
need to internalize the ecological and socio-economic                                      corporations (Csavas 1988 in Bailey & Skladany
costs ('externalities')   of shrimp farming          are                                   1991).
highlighted.     Other   recommendations        include                                       Shrimp farming started in Southeast Asia in
mangrove       conservation     and     rehabilitation,                                    traditional earthen ponds that depended on tidal
enforcement of existing legislation, and introduction                                      water exchange for wild seed supply and
of environment-friendly      aquaculture within the                                        maintenance of water quality, evolving to the
broader framework of community-based, integrated                                           deliberate stocking of wild or hatchery fry in ever-
coastal area management, e.g. the traditional,                                             increasing densities (Primavera 1991). The high
-extensive polyculture ponds in Indonesia.                                                 stocking rates in intensive ponds are supported by
                                                                                           feed and water management inputs to achieve yields
                                                                                           of up to 7-15 t ha-l year-l, 50 times the production
                                                                                           from traditional ponds (Primavera 1993).
                                                                                              The historical trends of shrimp production in
In 1995, more than 700000 tonnes (t, 'metric                                               leading Asian countries (Fig. 1) show a boom-and-
tons') of marine shrimp were farmed worldwide,                                             bust cycle -Taiwan     in 1987, the Philippines in
with around 80% from Asia (Rosenberry 1995).                                                1989, Indonesia in 1991-92, and China in 1993 -
The contribution  of farming to global shrimp                                              related to pollution   and disease problems. Other

Ci   1997   B1/lckwell    Science   Ltd
Socio-economic impacts of shrimp culture J H Primavera                     Aquaculture    Research. 199'      28, 815-82



Figure   I Production (thousand tonnes) of cultured shrimp in leading Asian countries (data from Rosenberry 1989-95;
Ferdouse 1990).

ecological effects of shrimp farming (e.g. loss of
                                                              outweighing the benefits by 4 to 1 (63 billion rupees
mangrove ecosystems. nutrient enrichment and
                                                              vs. 15 billion rupees annual earnings) in Andhra
eutrophication    of coastal waters. longevity of
                                                              Pradesh and by 1.5 to 1 in Tamil Nadu (Khor
chemicals and toxicity to non-target species.
                                                              1995a). Among others, these costs included loss of
development      of   antibiotic    resistance.    and
                                                              mangroves, salinization and increasing unem-
introduction of exotic species) are discussed in depth
by Macintosh & Phillips (1992). Primavera (1993).             ployment.
                                                                 Barraclough & Finger-Stich (1996) point out that
Briggs & Funge-Smith (1994). and Funge-Smith &
                                                              these social and environmental problems are only
Stewart (no date). The large demand for resources
                                                              the latest incidents in the broader processes
and ecosystem services (Ehrlich & Mooney 1982;
                                                              associated with the expansion of other monocultures
Folke 1991) by shrimp farming is described in
                                                              (e.g. banana, cotton, coffee and sugar) that have
Larsson. Folke & Kautsky (1994).
                                                              generated social exclusion and environmental
                                                              degradation. Hence, intensive shrimp farming
Socio.economic effects                                        repeats the pattern of unsustainable        growth
                                                              described for many other industries (e.g. Folke &
Modern shrimp farming has socio-economic costs
                                                              Kautsky 1992).
(Bailey 1988; Primavera 1993; Baird & Quarto
1994; Barraclough & Finger-Stich 1996) aside from
the ecological consequences listed above. A cost-            Loss of mangrove         ecosystems,       goods and
benefit analysis commissioned by the Indian                  services
Supreme Court concluded that shrimp culture
                                                             Culture ponds for shrimp and fish account for the
caused more economic harm than good. the damage
                                                             destruction of 20-50% of mangroves worldwide in

                                                                997 Blackwell Science Ltd, Aquaculture Research, 28, 815-82'
Aquaculture            Research,     1997,      28,      815-827                              Socio-economic impacts of shrimp culture J H PrimQvera

                                           Mangroves                                           Culture    Ponds
                                                                                                                         Ilocos Region( I )

                                                                                      ~   J                              CagayanValley ( II)
                         W'$$$$$$$$$$$$$$~                                                                               Central Luzon(III)+NCR

                                                             ~$~~$$~                                                     SouthernTagalog( IV)

                                                      WJ$$$$$$$~                                                         Bicol Region( V)
                                    W'$$$$$$$$$$$~                                                                       WesternVisayas (VI)
                                                                            ~$$~                                        Central Visayas ( VII )

                                                                              ~                                        I t.ostern Visoyos (VIII)
    ~$$$$$$$$$$$$$$$D$$$$~                                                                                             I Western Mindonao ( I X )

                                                                                  ~                                     Northern Mindanoo ( X )

                                                                               ~                                        Soothern Mindanoo(XJ)

                                                        .,                     I      WA"l        .,               ,    Centrol Mindanoo (XII)
    -70       -60           -50        -40            -30       -20          -10       0         10      20       30

                                                             Change in area ( x 103 ho )
Figure 2 Change in area (thousand hectares) of mangroves and brackish water culture ponds, from 1951 to 1990. in
geographical regions of the Philippines (from Primavera 1994).

recent decades. in addition to agricultural. industrial                                   well-being     of coastal communities      for centuries
and residential development. In the Philippines.                                          through products used for fuel, construction, fishing,
approximately    half of the mangrove loss of                                             agriculture, forage for livestock, paper, medicines,
279000 ha from 1951 to 1988 resulted from the                                             textile and leather, and food items -mainly       fish,
development of culture ponds (Fig. 2: Primavera                                           crustaceans and molluscs (Macnae 1974; dela Cruz
1995). Minh Haiprovince. with the largest mangrove                                         1979; Christensen 1982; Tesoro 1984; Fottland &
area in Vietnam. has lost forests at an average of                                        Sorensen 1996). A positive correlation between
5000 ha year-l; shrimp farms have increased from                                          mangrove area and shrimp/fish catches has been
50000 ha in 1981 to 120000 ha in 1987 (Trinh                                              documented for the Philippines, Malaysia, Indonesia
1993). Reduction in mangrove areas in Ecuador in                                          and Australia (Primavera 1995 and references
1965-1984 was mainly due to the construction of                                           therein), and is reflected in the parallel decline
21 600 ha of shrimp ponds (Alvarez. Vasconez &                                            in Philippine mangroves (Fig. 3a) and municipal
Guerrero 1989). Around 50% of total denuded                                               fisheries (Fig. 3b).
mangrove area of 171 500 ha in Thailand in 1961-                                             In addition to a wide array of products, mangroves
1987 was converted into shrimp ponds (Aksornkae                                           generate a variety of ecosystem services such as
1988). In the Chokoria Sunderbans in Bangladesh,                                          coastal protection provided by a buffer zone during
most of the 7500 ha of mangrove vegetation in 1975                                        typhoons and storm surges, reduction of shoreline
has been cleared for shrimp farming, leaving only                                         and riverbank erosion, stabilizing sediments and
973 ha of scrub forest in 1988 (Choudhury. Quadir                                         absorption of pollutants (Saenger, Hegerl & Davie
& Islam 1994). This widescale expansion of shrimp                                         1983; Hamilton & Snedaker 1984).
culture    into mangroves has transformed             a                                      Destruction of mangroves along the Philippine
multifunctional ecosystem that generates a diversity                                      coastline accounts in part for the great losses to life
of resources and services into private ponds that                                         and property inflicted by an average of 20 typhoons
produce only one resource (Bailey 198 8) and degrade                                      and tsunamis each year -around         3000 deaths in
the environment at the same time.                                                         Zamboanga province in 1976, 1000 in northern
    Mangroves have contributed significantly                                 to the       Panay in 1984, and 7000 in Ormoc and other Leyte

~   1997   Blackwell      Science   LId.   Aquaculture    Research,   28,   815-827                                                                817
Socio-economic impacts of shrimp culture J H Primavera                 Aquaculture Research. 1997. 28. 815-827




towns in 1991. In the Chokoria Sundarbans in             nilad. On a more poignant note, Professor Phan
Bangladesh. mangroves protected villagers from a         Nguyen Hong of the Vietnam National Pedagogic
1960 tidal wave but a cyclone caused thousands of        University decries the shrimp rush in his country
deaths and enormous property damage in 1991              thus: 'During the two wars [of resistance against
after the installation of shrimp farms {Choudhury.       the French, and later the Americans], Minh Hai
Quadir & Islam et al. 1994).                             mangroves had protected the people and soldiers
   Aside from sustainable uses {timber. fish) and        against the enemies' bombs and attacks. Sweat,
regulatory    functions   {prevention    of erosion.     tears and even blood were shed to protect and
maintenance of biodiversity. nutrient supply and         restore these valuable forests which are now being
regeneration). Ruitenbeek {1994) has described the       destroyed for some short-term benefits' (Hong 1996 ) .
information    function   {scientific. cultural  and        Most mangrove valuation efforts cover only
historical) of mangroves. Thro examples from the         marketed resources (Hamilton & Snedaker 1984 ) and
Philippines and Vietnam serve to illustrate the          ignore non-traded uses such as the regulatory and
historical function. The Philippines. premier city of    information functions and other ecosystem services
Manila probably owes its name to the mangrove            described by de Groot 1988 (in Folke 1991). This is
species Scyphiphora hydrophyllacea. initially named      evident in the low values « US$ 100 ha-l year-l:
Ixora manila by the Spanish priest Blanco in 1837.       Table 1) assigned to mangrove systems because they
the species name being associated with the city          only include marketed forestry and fishery products.
{MerriII1918). When the Spanish arrived in 1570.         Yet the traditional subsistence use of fuelwood,
the swampy bay was called Maynilad. in reference         medicines and food contributes yearly over US$l 000
to the abundance of S. hydrophyllacea. locally called    per household in certain areas in Thailand (McNeely

818                                                      @ 1997 Blackwell Science Ltd, Aquaculture Resean;h, 28, 815-827
Aquaculture               Research.     1997.       28.       815-827                              Socio-economic impacts of shrimp culture J H Primizvera

Table I Economic values placed on products and services of mangrove systems (after Primavera 1993)

                                                                                                         Value (US$
Country                    Year          Product or service                                              ha-' year-')     Reference

Puerto        Rico         1973          Complete         mangrove       ecosystem                                1550    Hamilton & Snedaker       (1984)
Trinidad                   1974          Complete         mangrove       ecosystem                                 600    Hamilton & Snedaker       (1984)
                                         Fishery products                                                           125
                                         Forestry products                                                           70
Fiji                       1976          Complete         mangrove       system                             950-1250      Hamilton & Snedaker       (1984)
                                         Fishery products                                                          640
Indonesia                  1978          Fishery products                                                            50   Hamilton & Snedaker       (1984)
Indonesia                  1978          Forestry (charcoal, wood chips)                                         10-20    Hamilton & Snedaker       (1984)
                                         Charcoal production          .
Thailand                  n.d.                                                                                    4000    McNeely    & Dobias (1991)
Thailand                   1979          Fish (inside mangroves)             and mangrove-                         130    Christensen    (1982)
                                              associated       species     (caught outside)
Thailand                  1982           Fish and shrimp                                                       30-2000    Hamilton & Snedaker       (1984)
                                         Forestry products                                                      3D-400
Brazil                    1981-2         Fish (based on extent of open water)                                      769    Kapetsky (1987)
Malaysia                  1979          Shrimp and fish (including                estuaries and                   2772    Gedney, Kapetsky        & KuhnhoJd (1982)
Malaysia                  n.d.           Fishery products                                                          750    Ong (1982)
                                        Forestry products                                                          225
Malaysia                  n.d.          Managed forest (sustained                 harvest)                      11561     Salleh & Chan (1986)
India                     1985          Complete system (including fishery products,                            11314     Untawale (1986)
                                          maintenance of fauna, air/water

& Dobias 1991).                        When          complete            systems are              Land conversion,         privatization          and
considered, much higher figures of US$100Q-                                                       expropriation
11000 ha-l year-l (Table 1) place mangroves on a
                                                                                                  All across Southeast and South Asia, residential,
par with intensive shrimp culture that gives net profits
                                                                                                  agricultural and forest lands are being converted
of$11 600 ha-l year-l (Chamberlain 1991).
                                                                                                  into shrimp farms. Even burial grounds, pastures,
   An expanded cost-benefit analysis (CBA) was
                                                                                                  areas for drying nets and other common land have
applied to Fiji mangroves based on the whole
                                                                                                  not been spared by the shrimp fever. In many
mangrove ecosystem, including interactions of
                                                                                                  cases, this has involved a direct buying out by big
ecological, economic and institutional factors (Lal
1990). The CBA gave a negative net present value                                                  companies of small-scale landowners. Often, salt-
for alternative uses (over a 50-year planning                                                     water contamination by adjacent shrimp ponds
horizon), that is, mangrove reclamation for shrimp                                                makes agricultural         land       barren      (see following
or rice will not give positive returns. A similar                                                 section) and the only option of poor farmers with
CBA of the Bintuni Bay mangroves in Irian Jaya,                                                   no capital for aquaculture is to sell their land.
Indonesia by Ruitenbeek (1994) incorporates                                                         In India, the enclosure of beaches for pumps and
linkages among mangrove conversion, fisheries                                                     powerhouses has deprived fishers of access to fishing
productivity, traditional values, etc. Under a scenario                                           grounds       and parking       places for         fishing    boats
of linear but delayed 5-year linkages, the optimal                                                (RajagopaI1995).        Indian fishing communities who
management strategy is selective cutting (vs.                                                     once were called pattapu raja, meaning kings of the
clearcutting) of harvestable mangroves. Noteworthy                                                coastline,      now     find      themselves          refugees      of
in both studies are the values reflected for non-                                                 aquaculture development (Shiva 1995). Whereas
marketed functions such as subsistence uses, erosion                                              public beaches have been privatized by shrimp
control and filtering services.                                                                   culture in India, private and communal                     property

~      1997   Blackwell      Science   LId.    Aquaculture     Research,    28,   815-827                                                                          819
Socio-economic impacts of shrimp culture J H Primavera                  Aquaculture Research. 1997. 28. 815-82

has ceased to be sacred in Kedah state, Malaysia          shrimp is destined for luxury export markets. The
(Seabrook 1995). Against the objections of small          development of shrimp culture is driven by economic
farmers, the state government has acquired their          realities, not the goal of improved domestic nutrition.
land by invoking 'economic benefits' (as allowed          A shrimp crop in Thailand earns up to 30 times the
under the Land Acquisition Act of 1960) to be             profits in rice farming, but almost all of it is exported
gained from a planned tiger prawn (Penaeusmonodon         (Table 2), whereas rice remains the staple of millions
Fabricius) project in cooperation with a Saudi            of Thai and billions of Asians. Shrimp culture has
Arabian company.                                          adversely affected food security through (a) loss of
   When intensive farming is practised, the life span     ricelands by pond conversion or salinization, (b )
of ponds does not exceed 5-10 years because of            shifting of culture ponds from milkfish and other
attendant problems of self-pollution and disease. In      domestic food crops to shrimp, and (c) declining
some cases, entrepreneurs have moved on to other          nearshore fish, crustacean and mollusc catches
areas in a pattern called 'rape-and-run' and the          associated with mangrove deforestation.
sterile lands are no longer available for agriculture        Decreasing rice production from around 40 000
or aquaculture. These abandoned areas do not              t in 1976 to only 36 t in 1986 in Satkhira,
appear in worldwide        estimates of the land          Bangladesh can be traced to salinization and loss of
appropriation by shrimp farms, which totalled 1.14        soil fertility as saltwater canals from shrimp ponds
million ha in 1995 (Rosenberry 1995).                     cut across paddy fields (Shiva 1995). Hence the
                                                          complaint of local villagers: 'Prawn revolution at
                                                          the cost of [the] rice bowl' (Parthasarathy 1994).
Salinization   of soil and water                          Moreover, shrimp monoculture has led to the decline
                                                          of traditional pokali fields in India and Bangladesh,
Water use in shrimp culture affects the surrounding
                                                          where alternating rice and shrimp/fish harvests have
environment through extraction of ground water
                                                          been sustainable (Baird & Quanto 1994). Consumer
and discharge of pond waste water. Heavy water
                                                          demand in rich nations drives the development of
use may draw from freshwater aquifers and reduce
                                                          the industry. Perhaps the demand would decrease if
supply of domestic and agricultural water, aside
                                                          consumers became aware of the devastating effects
from causing seawater contamination, especially of
                                                          caused by their consumption of cultured shrimp.
depleted aquifers. Salinization of natural waterways
can result from uncontrolled discharge of salty pond
water, as in Songkhla, Thailand, where horses died
after drinking canal water (Anonymous 1991c). To          Marginalization,        rural    unemployment          and
quote a Philippine daily: 'Cebuano [people] drink         migration
seawater as prawn farms proliferate' (Anonymous
                                                          A 1989 study of two coastal villages in Panay,
                                                          central Philippines, concluded that the economic
  Communities adjacent to shrimp farms in
                                                          benefits of shrimp culture did not trickle down
Bangladesh, Sri Lanka, Indonesia and the Philippines
                                                          to the residents but remained with the farmers,
experienced salinization or complete drying up of
                                                          entrepreneurs and traders (Amante, Castillo &
shallow wells for domestic water supply, and
                                                          Segovia 1989). Instead of improving living standards
browning of previously green orchards and ricelands
                                                          and village welfare, shrimp farming brought about
(Yap 1990; Gain & Moral 1994; Gain 1995). Water
                                                          social displacement and marginalization of fishers.
salinization and longer hours to collect drinking
                                                          Municipal fishers in the Philippines in 1987 exceeded
water from distant sources moved local women to
                                                          by almost threefold the number of workers in
pressure a shrimp company to supply free water to
                                                          aquaculture, but earned only half the income of the
600 fisherfolk in Nellore district, India (Shiva 1995).
                                                          latter (Table 3). The introduction of shrimp farming
                                                          to the Chokoria Sunderbans in Bangladesh did not
                                                          improve the socio-economic status of.poor people -
Food insecurity
                                                          fishers became daily labourers, peasants lost their
Global food security needs are used to justify the        grazing lands and others became jobless (Choudhury,
heavy promotion and subsidy of aquaculture                Quadir & Islam 1994).
development by national and international lending            Declining municipal fisheries yields (Fig. 3b) in
agencies. This is a paradox. because most cultured        the Philippines may be traced to loss of mangrove

820                                                       f:) 1997 Blackwel! Science Ltd, Aquaculture Research, 28, 815-827
Aquaculture Research. 1997. 18. 815-827                                                           Socio-economic impacts of shrimp culture J H Primavera

hectarage (Fig. 3a). among other factors. The                                                    labour-intensive. A 40-ha shrimp farm in India
conversion and salinization of rice and other                                                    employs only 5 labourers while an equivalent rice
agricultural lands also leads to the marginalization                                             farm would need 50 (Shiva 1995). In Indonesia. a
of coastal rural communities. Dispossessed farmers                                               rice crop requires an average of 76 work days ha-l
are forced to seek work elsewhere. migrating to                                                  compared with 45 for an extensive shrimp farm
the cities and swelling the ranks of the urban                                                   (Hanning 1988 in Barraclough & Finger-Stich
unemployed (Alauddin & Hamid 1996) and leaving                                                   1996). Employment of local people in shrimp farms
women and children alone for long periods (Shultna                                               is often limited to low-paying. unskilled jobs such
1994 in Barraclough & Finger-Stich 1996). The                                                    as labourers and guards. while technical and
development of shrimp farming in the Satkhira                                                    managerial positions are reserved for outsiders.
region of Bangladesh has displaced nearly 120 000                                                Moreover. funds invested in these farms are mostly
people from their farmlands (Utusan Konsumer in                                                  generated from the outside. therefore profits also
Baird & Quarto 1994).                                                                            leave the community. Three-quarters of the shrimp
   Modern shrimp farms are capital- rather than                                                  farmers-investors in the coastal areas of Khulna and
                                                                                                 Satkhira in Bangladesh in the early 1990s were
                                                                                                 businessmen from outside the local community
Table 2 Comparison of land and financial status between                                          (Shultna 1994 inBarraclough&Finger-Stich        1996).
rice and shrimp                 farming          in Pak Phanang.                  Southern       One reason was that the lease fee was beyond the
Thailand (from Boromthanarat                             1995)                                   reach of local people.
                                                                                                    The allocation of resources for shrimp farming
                                  Rice farming                   Shrimp      farming
                                                                                                 and the distribution of benefits depends on the social
                                                                                                 context and institutional framework (Barraclough
Farm area (ha)                    2                              0.8
                                                                                                 & Finger-Stich 1996). Where land and other
Cost of land                      3000-10          000           300   000--600     000          resources are under the control of a small elite. most
  (bahtha-1)a                                                                                    shrimp production is concentrated in a few large
Rental (ha)                        10%(1.12)                     460;0(0.64)                     entrepreneurs as in India and Bangladesh. But most
                                   1000;0 local                  270;0 outsider         .
Land ownership
                                                                                                 shrimp farms in Thailand are operated by small-
Source of income                  250;0 rice + 750;0             750;0 shrimp      +
                                  other                          25% other
                                                                                                 and medium-sized farmers (Kongkeo 1995) where
Market                             100% local                    950;0 export                    land is widely distributed. This is also the case in
Investment                        500-15000                      100000-1         500000         Vietnam. where land and other natural resources
  (baht      ha-1)a                                                                              belong to the State (Sinh 1994).
Net    return                     3000-        1 0 000           100000-200000

  (baht      per    crop)a                                       or 0- 1 000      000

Loss     (baht     per            none                           10000-350000                    Social u~st          and conflicts
                                                                                                 The capital-intensive nature of high-density shrimp
a25 baht         = US$ 1                                                                         culture has favoured the entry of multinational

Table 3 Comparison of municipal. commercial and aquaculture sectors in the Philippine fisheries (Primavera 1994)

                                                                       Municipala                   Commercialb                Aquaculturec

Production         (t), 1971 (% of total)                               542904          (53.1)      382276   (37.4)            97915    (9.6)
                          1991 (%of       total)                       1146765(44.1)                759815   (29.3)            692401    (26.6)
Employmen1,              1991 (no, of persons)                           675677                      56715                     258480
Gross monthly income,                  1987 (p)d                             1986                    19695                        3721

"Vessels.;; 3 gross tons.
bVessels> 3 gross tons.
"Includes pond. pen. cage and mollusc culture.
d20 p (peso) = US$ I. (1987 rate).

<e! 1997     Blackwell       Science    Ltd,    Aquaculture      Research,   28.815-827                                                             821
Socio-economic impacts of shrimp culture J H Primavera                             Aquaculture Research. 1997. 28. 815-827

corporate investors or the national elite. They can                  mangrove destruction associated with shrimp
provide the necessary capital. have easier access to                 culture development. Official laws. decrees and
permits, credits. subsidies. and can absorb financial                regulations prohibiting the use of mangroves and
risks. In this context. local communities in coastal                 agricultural land for shrimp pond construction are
areas and small farmers are disadvantaged.                           often ignored through lack of sanctions and
   Powerful     landlords     and    elected    state                enforcements.
representatives in Andhra Pradesh. India connived                       With their very survival at stake, villagers have
with local civilian and military authorities to                      organized themselves, aided by non-governmental
circumvent laws and acquire wide areas for shrimp                    organizations, and have started to fight back. Small
culture (Gain 1995). Despite non-compliance with                     farmers in Andhra Pradesh were arrested in 1994
the required voluntary        consent of 85% of                      for defying plans to convert paddy to prawn farms
landholders. well-connected city folk in Bangladesh                  (Nayak 1995; Rajagopal1995). In February 1995,
used similar links with political leaders and the local              hundreds of farmers in Kerpan, Malaysia lay down
administration to lease land for shrimp farms (Gain                  in the path of bulldozers; 33 were arrested and jailed
1995). MeltzofT & LiPuma (1986) highlight the                        (Seabrook 1995).
duality of interests that pervades the Ecuadorian                      Other such confrontations             have turned violent -
shrimp industry -government      officials tasked to                Karunamoi Sardar, a landless woman protester, was
oversee the industry are also shrimp producers                      murdered in 1990 (Gain 1995) and at least two more
and exporters with personal economic and political                  villagers opposing shrimp cultivation in Bangladesh
interests. Corruption is a major cause behind the                   have been killed, one of them by a bomb attack

Table 4 Matrix of ecological and socio-economic values and problems of brackish water pond culture compared with
intact or managed mangrove systems. (Primavera 1993)

                                                  Intactlmanagedb                      Brackish water pond culture
                                                  mangrove          system

                                                                                       Milkfish          Shrimp   farming"

                                                                                                         E         s

  1 Communal        ownership     of resources
  2. Mangrove       products
  3 Coastal protection
  4. Nearshore      fisheries   production        +
  5. Domestic    food supply                      +                                    +
  6. Foreign exchange                             -1+                                                              +
  7. Income                                       +                                   d                            d
  8. Employment                                   +                                                                e
  9. Competition      for land, credit, etc                                            +

  1. Pollution (in and outside       pond)
  2. Chemical    toxicity
  3. Public health risks
  4. Displacement       of native species
  5. Spread of parasites        and diseases
  6. Water and soil salinization

a+ , present; -, absent,
bpor silviculture     and/or fisheries,
cE, extensive; S. semi-intensive; I, intensive.
dOnly middle and upper income classes.
eOnly technical and managerial expertise.

822                                                                 Cl1997   Blackwell Science Ltd, Aquaculture Research, 28, 815-827
Aquaculture Research. 1997. 28. 815-827                                      Socio-economic impacts of shrimp culture 1 H PrimQvera

(Khor 1995b; Alauddin & Hamid 1996). The houses                             nature's productivity in the sea and the productivity
of landless families opposing shrimp         farm                           of fishing communities. ..[and place] the luxury
development in Tennampattinam. Tamil Nadu were                              consumption of shrimp by rich Northern consumers
burned down (Mukul1994; in Barraclough & Finger-                            and the profits of corporations above the need for
Stich 1996). In the Vietnamese village of Thong                             drinking water, food and livelihoods of local fishing
Chau in the Red River Delta. one man died during                            and farming communities.' The environmental and
a conflict between fishers and shrimp pond owners                           social damage caused by such value judgments is
(A. Quarto. personal communication)" There are                              reflected in Table 4 where problems of pollution,
reports from Hua Sai district, Nakkon Si Thammarat                          public health risks and salinization caused by
in Tqailand of shrimp farmers boasting that the                             intensive shrimp farming are in stark contrast to
amount needed to silence a (protesting) rice farmer                         the values of communal          ownership,    coastal
is equivalent to sales of only 20 kg of prawns. Out
                                                                            protection and domestic food supply intrinsic to
of desperation. one of 4000 displaced rice farmers
                                                                            intact mangroves (Primavera 1993). These values
shot dead a neighbouring shrimp pond operator
                                                                            need to be monetized to provide more comprehensive
(Anonymous 1991b). To prevent theft of his crop,
                                                                            information    to   national    governments    and
a powerful shrimp owner in Tehtultela. Bangladesh
                                                                            international funding organizations, which have
has. with the help of hired guards. banned people
                                                                            embarked on ambitious development programmes
from moving in the vicinity of the farm after dark
                                                                            for shrimp aquaculture. Institutions that protect
(MAP 1996). Villagers can no longer fish for crabs.
                                                                            local communities and the environment from short-
women cannot leave their houses to attend to their
                                                                            term profit-makers must be developed and supported
biological needs at night. and half the males have left
                                                                            and their rules must be enforced.
the village because of the presence of armed guards.

Conclusion        and recommendations                                       Mangrove        valuation   and economic         analysis

According to Vandana Shiva (1995): 'Intrinsic to                            There is a need for further research to yalidate the
shrimp farming are value judgments that devalue                             mangrove-otTshore fisheries connection (Fig. 3), and

                                                                    To produce       1 kg of shrimp

                                                                I                                          \
                                                            (                                                      Drinking water
                                                                                                                   Domestic food supply
                                                                              ~                                    Mangrove goods
                                                                                                                    Fisheries production
                                                                                                                    Typhoon damage



                                                                                       "'                  P1'7        Production

                                           Labour       ~

Figure 4 Comparison of the
apparent and true costs of
producing 1 kg of farmed sbrimp
(data from Auburn University,
1993). P (Phil. peso) 26.8: US$l
(1993 rate).
                                                    Apparent        costs                        True   costs

C>1997 Blackwell Science Ltd. Aquaculture Research. 28, 815-827                                                                         82
Socio-economic impacts of shrimp culture J H Primavera                    Aquaculture     Research. 1997. 28, 815-827

to refine valuation of mangrove systems. As shown          and other rehabilitation programmes (World Bank
in Table 1. the fishery harvests from mangrove             1989; Evangelista 1992). Increased fees may also
systems have much greater value than forestry              slow the rate of mangrove conversion because the
products. Following the pioneering work of Lal             return on investment will be lower.
(1990) and Ruitenbeek (1994), more CBA studies                Complementary to the research thrusts discussed
incorporating the ecosystem approach are needed.           earlier are various action-orientated programmes
A theoretical framework for such valuation has been        that can be instituted at the local and national levels
developed (Maler. Gren & Folke 1994) but empirical         (Primavera 1993,1994). These include enforcement
tests have not yet been made,                              of existing pro-environment laws; conservation of
   The studies by Lal (1990) and Ruitenbeek (1994)         remaining mangroves and rehabilitation of degraded
have noted that the exact relationship between             areas;   introduction   of    environment-friendly
mangroves and coastal fisheries/fish fauna is              aquaculture of seaweeds, molluscs, fish in cages and
complex and not known.           Two mechanisms            other crops that are compatible with mangroves;
postulated to explain the link between fisheries           implementation   of an integrated coastal area
yields and mangrove (and other intertidal) areas are       management programme that is community-based;
trophic subsidy through detritus export, and use as        and other actions recommended by Barg (1992),
nursery grounds (Boesch & Turner 1984). However.           Primavera (1993), Barraclough & Finger-Stich
there is little evidence that the exported detritus        (1996) and Funge-Smith & Stewart (no date)
enhances offshore productivity (Lee 1995) and              among others.
fisheries yields; the connection between offshore
prawn catches and mangroves may lie in the nursery
function (Hatcher. Johannes & Robertson 1989).
Mangroves act as shrimp nurseries by providing             Acknowledgments
food and/or shelter from predation.
                                                           Thanks are due the International Foundation for
   In addition to updated mangrove values, a more
                                                           Science for the invitation to present this paper and
accurate economic analysis of shrimp production
                                                           the travel grant to Can Tho, Vietnam; Carl Folke for
from culture ponds is needed. The social and
                                                           his valuable comments and suggestions; Alfredo
ecological      impacts     heretofore      considered
                                                           Quarto, Kate Cissna and Meena Rahman for help in
'externalities' should be internalized in the final
                                                           retrieving references; Junemie Lebata for typing the
valuation of the shrimp product (Fig. 4) as Folke,
Kautsky & Troell (1994) did for salmon aquaculture.        tables; and Edgar Ledesma for the figures.
Selected case studies should deal with the political
economy of shrimp farming and environmental
degradation in specific ecological, social and political
contexts because the key question is who bears the         References

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