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					                              CHAPTER TWELVE

                           RURAL LAND USE

12.0 Introduction

    Agriculture, animal husbandry and fisheries
    constitute the major vectors for the use of
    environmental resources. To discuss the
    emerging scenario in this regard is the
    objective of this chapter.

12.1 Agriculture
    The state of West Bengal is primarily inhabited by rural population. The rural
    economy largely depend on agriculture. It is recorded that nearly 50% of the
    working people are directly connected with agriculture. Of these, nearly 27%
    represent large, medium or small farmer communities while the rest act as
    agricultural farm labourers.

    12.1.1 Some Trends

    Of the 8684 thousand hectares of total area, nearly 67% are cultivable. The
    intensification of cropping in the agricultural sector in West Bengal has placed the
    state above others during the last decade. The cropping intensity in 1994-1995
    stood at 163.

    The growth of the agricultural sector in the state is related to the successful
    implementation of land reform programme, which involved distribution of surplus
    land (above ceiling) to the landless, and ensuring security for tenure of
    sharecroppers by registering their name under „Operation Barga‟. The agricultural
    productivity, however, is related to use of chemical fertiliser, pesticides and

    It may be noted that while the area under rice yield has increased, productivity of
    other grains as also of oilseeds has declined. The propensity to intensify rice
    cultivation at the cost of other crops needs careful examination as it might lead to
    decline in the production of vegetable protein and fatty substance.

    The decline in net cropped area from 5515.51 thousand hectare in 1984-85 to
    5463.59 thousand hectare in 1994-95 on one hand, and increase in permanent
    pasture and other grazing land from 0.86 thousand hectare to 6.36 thousand
    hectare on the other, reveal an undesirable trend. Amongst 17 districts of West
    Bengal, except for 6 districts, crop-area has declined in all with the progress of
12.1.2 Use of Resources

Agriculture requires the use of many types of material resources. Over utilisation
of any of these may cause serious environmental impacts. The emerging
scenario in this regard demands careful attention.

The agricultural sector is identified as the largest user of water resources. During
1994-95, more than hundred thousand hectares of land has been irrigated under
minor irrigation programme.

A significant part of this irrigation (75%) has been through abstraction of ground
water by shallow and deep tubewell. It is estimated that nearly 4.5 million
hectares of land could be irrigated (from present 2.9 million hectares), of which
only 1.3 million hectares could be irrigated by surface water and 3.2 million
hectares by ground water. The impact of utilisation of ground water needs to be
assessed from environmental aspect.

The state has 7% of the total cultivated land chronically under degradation and
erosion. Besides other efforts to bring the area under effective use, the scheme
of National Watershed Development Project in Rainfed Area (NWDPRA) has
been initiated in major districts except for Haora and Nadia. A total of 170 blocks
have been brought under the scheme with a target of 95250 hectares. As a part
of these programmes, efforts are also being made to introduce dry land farming in
laterite districts of Puruliya, Bankura, Birbhum and Medinipur (West) and 59
blocks of Bardhaman Districts. This programme requires development of micro
watershed and about 301 micro watersheds have been identified; work is being
undertaken in 166 micro watersheds covering an area of 30,000 hectares.
Appropriate soil and water management, cropping system selection, judicious use
of fertilisers could make it a environmentally sustainable agricultural practice.

The water harvesting system in the state vis-à-vis agricultural demand needs a
review. In North Bengal, annual mean rainfall is highest : Darjiling (3212 mm),
Jalpaiguri (4136 mm), Koch Behar (3193 mm), Dinajpur (1802 mm). The districts
traditionally marked as drought prone in the western part has also sufficient
rainfall: Puruliya (1365 mm), Bankura (1271 mm), Birbhum (1234 mm), West
Bardhaman (1271 mm). The problem centres around inadequate system of
holding the water from rains. The wetland conservation policy has to be inter-
linked not only with fisheries but with mainstream agriculture.


The use of N P K fertiliser has remained more or less unchanged. The extent of
use of fertiliser has remained more or less constant, around 0.73 to 0.75 mt. Use
of organic manure remained extremely inadequate. Concerted efforts are to be
made to campaign for wider use of organic manure and manufacture of organic
fertiliser. Vermiculture may positively help in increasing soil fertility and a village
based campaign could be launched.


The trend of use of non bio-degradable pesticides, both chlorinated hydrocarbon
and organo-phosphate, continues unabated in India. Among the seven states
with highest use of pesticides, West Bengal ranks prominently. Recent
investigations show pesticide residues in many vegetable and other food items.

Integrated Pest Management (IPM) in paddy field has been reported to be
successful in many areas. Emphasis on natural bio-control agent and use of eco-
friendly plant products (e.g., neem, tobacco, etc.) is to be more widely advocated
along with cultural control based on agro-climatic zone.

HYV Seeds

The impact of introduction of high yielding varieties of seed (HYV) on the one
hand and loss of folk varieties on the other has never been assessed in the state.
A systematic marketing strategy has led to a dangerous trend of homogenisation
of agriculture (see Figure below) Indigenous varieties are often neglected or
thrown out without realising the potentiality of germ plasm. The HYV culture could
lead to large scale epidemics and the cost of control could be beyond farmers‟
means. The state has to introduce community based germ plasm bank for short
and medium term preservation of indigenous varieties of seeds so that useful
genes could be isolated and recombined with the one currently being used. The
seed policy of the State Government needs a critical review by panel of experts
and the farmers community.

                                   Area under High Yielding Varieties (HYV) in West Bengal
                                                             100     100
  Percentage of Total Area

                             80              72.4                                            73.87
                             50                                                      40.76


                                      Rice (HYV)

                                                                                       Rice and
                                        of Total

                                                                of Total



                                                              Category            1984-85      1994-95

Source : Economic review 1995-96

12.1.3 Features of Homogenisation of Cropping

An analysis of agricultural production and productivity of selected crops
figures in West Bengal (base triennium ending crop year 1981-82=100)
shows that, of the 10 food-grain crops studied, other than for rice and
wheat, areas under cultivation has variably decreased between 1985-86
and 1994-95. In case of pulses an area under production has been
reduced to nearly 50 per cent with a consequential reduction in the total
production of gram, arhar, moong and musur all of which variably form a
regular component of staple diet. In case of non-food grains, the analysis
shows that other than for oil seed, cotton, tea, spices the area under
cultivation and total quantum of production has significantly reduced
specially for fibre crops and jute. In case of cotton while the area under
cultivation remains the same, the production has declined to less than 50
               percent as also the rate of productivity (see Figures below).

                            Table : Agricultural area of selected crops in West Bengal

                                                                                                                                                                              Area 1985-86

                60                                                                                                                                                            Area - 1994-95


                                                                                                                                                Mu ng




                      Table: Agricultural production of selected crops in West Bengal


                                                                                                                                                                         Production 1985-86
                                                                                                                                                                         Production - 1994-95


                                                                                                                                        Mu ng





                     Table: Agricultural productivity of selected crops in West Bengal


                                                                                                                                                                        Productivity 1985-86
                                                                                                                                                                        Productivity - 1994-95


                                                                                                                                      Mu ng




                                  Table: Agricultural production of selected crops in West Bengal




                            150                                                                                                                            Production 1985-86
                                                                                                                                                           Production 1994-95



                                                                                                                Cotto n





                                          Table: Agricultural area of non-food crops in West Bengal




                                                                                                                                                                Area 1985-86
                                                                                                                                                                Area 1994-95


                                                                                                              Cotto n




                                  Table: Agricultural productivity of selected crops in West Bengal


               100                                                                                                                                        Productivity 1985-86
                 80                                                                                                                                       Productivity 1994-95
                                                                                                    Cotto n




                    90                                 Utilisation of land in West Bengal by district in 1994-95



Area (in hactare)

                                                                                                                                                                                                                                     Net area show n
                                                                                                                                                                                                                                     Current fallow s
                                                                                                                                                                                                                                     Area under forest

                    30                                                                                                                                                                                                               Other uncultivated land
                                                                                                                                                                                                                                     excluding current fallow s
                    20                                                                                                                                                                                                               Area not available for
                                                                                                                                                                                                                                     Area according to village
                    10                                                                                                                                                                                                               papers

                                                                              Hoog hly



                                                                                                                                                        Uttar & Dakshin


                                                                                         24 Parganas(N)


                                                                                                                                         Mu rshidabad

                                                                                                          24 Parganas(S)

                                                                                                                                                                                                            Coochb eh ar
                                                                                                                                                            Dinajpu r
12.1.4 Need for Agro climatic Regional Planning

India has been divided into 15 distinct agro climate zones. The state of West
Bengal has Eastern Himalayan Zone (Darjiling, Koch Behar and Jalpaiguri
districts). Eastern Plateau and Hill Zone (Puruliya district) and lower Gangotri
Plains Zone (rest of West Bengal). It is necessary that diversification of cultivated
crops be attempted in tune with the varying character of resource endowments of
these regions.

The recent emphasis on decentralised planning (a concept supported by 73rd
and 74th Constitutional Amendment) could be effectively utilised in a agro
climatically homogenous region based planning ; such a process could help to
arrest soil depletion, salinity and water logging and ground water depletion. The
concept has been accepted by the Planning Commission in 1988. The state
could now embark upon a planned development of resources in an integrated
and sustainable manners. The Gram Panchayats (3324), Panchayat Samitis
(340), Zilla Parishads (17) network could be participants in such an integrated
planning process. “Sthayee Samities” or permanent committees (10 at Zilla
Parishad and Panchayat Samiti level) may have a definitive role in such a
process (Ingty et al. 1996).

12.1.5 Scenario of Pesticides

The use of chemical pesticides was formally started in India after
Independence on a small scale (1985) by importing DDT to control
Malaria and BHC to control locust damage. With intensive agriculture, the
use of pesticides has increased in terms of range and quantity. Pesticide
industry has been identified as one of the most polluting industries due to
product-toxicity, manufacturing processes and waste generation and

In agricultural sector, pesticides are used in the pre-planning state (before
seeding), pre-emergence stage (from seeds) and post emergence stage.
Besides control of agricultural pests, use of fungicides to kill fungus
pathogens, herbicides to control unwanted weeds and nematicides and
rodenticides to control nematode and rodent pests is on the rise.

In West Bengal, 65 varieties of indigenously produced pesticides are
variably used. Of these, 16 varieties have not been used or projected
during 1995-96, 1996-97 and 1997-98. Of the 49 varieties used and
projected, 23 varieties are insecticides, 14 are fungicides, 8 are herbicides,
4 are rodenticides etc. Besides 49 varieties of indigenously produced
pesticides, 31 additional varieties are imported to supplement control
efforts. As such, a total of 80 different pesticides are currently being used
in agriculture in West Bengal.

An analysis of use pattern of total pesticides used in the state, indicates an
increase of 4.4% between 1995-96 and 1996-97; but the same annual
growth rate is projected to be 15% from 1996-97 to 1997-98. Incremental
rate of growth is therefore very significant.

Of the indigenously produced pesticides, annual growth of demand is
sharply focused on 12 of the 23 varieties of insecticides for the year 1997-
98. An analysis of last three years data, with 1995-96 as base year could
show the trend of actual and projected demand in Table-12.1.5(A). A
more detailed analysis of consumption of pesticides since 1980-81 shows
that between 1980 -81 to 1982 -83 the consumption rate varied between
240-300 MT. while it reached above 5000 MT during 1986-87 and 1988-89.
      Table-12.1.5(A) : Trend in the Use of Insecticides in West Bengal
                                  1995-96 to 1997-98

                      Name of            Percentage%          Projected demand
                    Insecticide        increase between        and percentage
                                          1995-96 and         increase between
                                            1996-97           1996-97 and 1997-
                  Dichlorovos                   0                     +34
                  Dimethsate                  +23                     +40
                  Endosulfan                    0                     +45
                  Ethron                        0                     +50
                  Lindane                     +75                     +92
                  Malatheon                   -39                     +74
                  Methyl Parathion            +25                    +37.5
                  Monocrotophos               +25                     +34
                  Phorate                     -18                     +59
                  Phosphomiclin                -9                     +34
                  Qninolphos                  -14                     +57

It is also noted that rate of consumption of pesticide in Agriculture in the state is
highest, in the districts of Haora, Hugli, Bardhaman and North and south 24
Parganas district, which have also high density of human population. Districtwise
consumption of pesticides for the years 1991-92 to 1996-97 are shown in Table-
       Table-12.1.5(B) : Consumption of Pesticide (Tech. Grade) in MT

                 District        1991-     1992-    1993-   1994-    1995-    1996-
                                 92        93       94      95       96       97
                 Darjeeling          103     110      120      110      110      110
                 Jalpaiguri          170     175      160      160      150      160
                 Cooch Behar         150     140      160      140      170      180
                 Jalpaiguri          432     425      440      410      430      450
                 W. Dinajpur         270     260      300      260      240      250
                 Maldah              325     330      300      320      300      360
                 Raigunj             595     590      600      580      540      610
                 Murshidabad         305     305      350      300      280      270
                 Nadia               345     345      350      305      300      270
                 Krishnanagar        650     650      700      605      580      540
                 24-Parganas         300     290      350      300      300      280
                      District          1991-       1992-       1993-        1994-     1995-      1996-
                                        92          93          94           95        96         97
                      24-Parganas           340          350          310       345         280     260
                      Haora                 215         220           220       220         200     190
                      Alipore Range         855         860           880       865         780     730
                      Hugli                 474         470           450       465         460     481
                      Bardhaman             864         865           900       845         770     881
                      Birbhum               220         225           280       220         240     220
                      Bankura               235         230           240       225         220     200
                      Puruliya              175         180           150       170         150     140
                      Bankura               630         635           670       615         610     560
                      Medinipur             595         600           600       580         500     520
                      Total                4612        4625          4790      4500        4210    4291
                       Source : Directorate of Agriculture, West Bengal.

Annual rate of demand of these pesticides is of concern for environmental
management. West Bengal being a monsoon rich state, the runoff rate of most of
these non-biodegradable insecticide is very high. This in turn can continue to
have direct impact on public health as well on domesticated animals, through the
soil and water system besides pesticide residual effect.
Table-12.1.5(C) : Banned Pesticides Used in West Bengal and in India (in million
       tonnes, technical grade).

                        Insecticides               1995-96                  1996-97          1997-98
                      Caraboryl                                 80                 40                90
                      Dimethoate                                70                 90               120
                      Dicofol                                   60                 50                60
                      Endosulfan                               220                220               400
                      Methy Parathin                           150                200               320
                      Phosphomidin                             330                300               450
                      Phorate                                  300                250               350
                      Diuron                                    10                    10               10
                      2-4-D                                     15                    70               70
                      Zinc Phosphide                             5                     5                5
[DDT is banned elsewhere but used in Public Health Sector, in India, including West Bengal to a
great extent]
Source : CPCB, 1994

Government of India has already imposed restriction on the use of 13 categories
of pesticides (on 31.12.92) which includes Lindane and Methyl Parathion. It is
noted that BHC which was the maximum used insecticide in West Bengal(1000
MT in 1995-96, 1200 MT in 1996-97 but not projected in 1997-98) has been
banned for use on vegetables, oil seeds and fruits by GoI. Under the same order
while 13 pesticides have not been approved for use in India and 12 others
(including common product like Toxaphane, Chlordane, Heptachlor and Adrian,
the last from 01.01.1994) have been banned, as many as 34 pesticides which
are banned or restricted in other countries are continued to be used in India
(CPCB, 1994). At least 10 of these 34 are recorded to be used in the state of
West Bengal as shown in Table-12.1.5(C).
With the intensification of agriculture through increased use of high yielding
varieties of seeds, the use of chemical fertiliser and pesticides began in the
1960‟s. It is estimated that pesticides protect more than half of the country‟s area
under cultivation. On an all India level pesticide consumption has risen 10 times
in 30 years (such data is not readily available for the state but may be equally
applicable). No regular monitoring of pesticides as residue on crop and crop
product soil and water is being done in India or in West Bengal.

A WHO study in mid 1980‟s from a series of samples taken from different parts of
India (a total of 1500 cereals, pulses, milk, oil & meat samples) had shown that
25 percent of the samples had crossed the safety limit. Milk samples taken from
50 lactating women had four times higher residue of insecticide than in 8 other
developing countries.
          Table-12.1.5(D) : Tolerance limits for Pesticides (in PPM)
                Pesticide     Food     Milled          Milk     Fruit   Vegetabl   Mea    Egg
                              grain   foodgrai       and its      s       es        t      s
                                s        ns          product
                Adrian         0.01              -      0.15      0.1        0.1    0.2    0.1
                Carbonyl(       1.5              -          -       -        5.0      -      -
                Chlordane      0.05              -      0.05      0.1        0.2      -      -
                DDT                          -          1.25      3.5        3.5    7.0    0.5
                Diazinon       0.05          -             -        -        0.5      -      -
                Dichlorov       1.0       0.25             -      0.1        0.5      -      -
                Dicofol (c)       -              -          -     5.0        5.0      -      -
                Dimethoat         -              -          -     2.0        2.0      -      -
                Endosulfa         -              -          -     2.0        2.0      -      -
                n (d)
                Fenitrithio    0.02              -      0.05      0.5        0.3   0.03      -
                Heptachlo      0.01       0.02          0.15        -          -    0.0      -
                Hydrogen       37.5        3.0              -       -          -      -      -
                Hydrogen       0.05       0.01              -       -          -      -      -
                Inorganic      25.0       25.0              -   30.0           -      -      -
                Lindane        0.25          -            0.2     3.0        3.0    2.0      -
                Malathion       4.0        1.0              -     4.0        3.0      -      -
                  Source: C.C.F.S., New Delhi (a) 10 PPM for leafy vegetables, 0.2 for
                        potatoes, 1.0 PPM for maize cob, (b) 0.3 PPM for sugar beet, (c) 5.8
                        PPM for tea, (d) 0.5 PPM for cotton seed and 0.2 PPM on cotton seed

Lack of information continues to be a key problem that has led to continuous use
of pesticides in the state and country. Data on the residue level remain sporadic
while demand for pesticides continues to grow significantly. While acute effects
of pesticides currently being used extensively have mostly been well documented
elsewhere, data on chronic effects of pesticides remain totally inadequate.

However, chlorinated hydrocarbons e.g. DDT, BHC, Lindane, Endosulfan, are
known to be stored in body fat of man and animals Organo-phosphorus
compounds (Matatheon etc.) easily break down and do not accumulate in animal
tissue, but can cause mycosis, salivation, abdominal pain, nausea and death.
Cumulative effects of long term accumulation of pesticides may lead to renal
dysfunction, haematological abnormalities, abnormalities of brain tissue, etc.

Tolerance limits for Pesticides (in PPM) on different items of human food, may be
used as indicator base for monitoring in future. These limits are noted in Table-

Livestock forms a vital component of agricultural economy of the state.
An analysis of livestock growth pattern, shown in Table-12.2(A), indicate a
positively upwardly trend between 1961-1989, specially for Cattle, Sheep,
Goats, Poultry, Pigs. Buffalo population had, however, reached the peak
in 1977 but has declined even in comparison with 1961 census figure. In
terms of total live stock population 61 percent increase could be noted
between 1966 -1989 period. The position as revealed from the Animal
Census of 1992 is presented in Table-12.2(B).

        Table-12.2(A) : Growth of Livestock (Numbers in ‘000)

               Livestock                                     Year
                                   1961      1966        1972 1977        1982      1989
               Cattle              11476       12845      11878   14435   15658      16510
               Buffaloes             986        1048        824    1268     987        965
               Sheep                 535         638        793    1079    1365       1460
               Goats                4513        4852       5211    7335   10916      11890
               Horses and
               Ponies                 25          27         15      17      22         17
               Poultry             11772       12932      15492   18126   26670      35824
               Pigs                  NA          144        361     556     768        897
                 Source : Statistical Abstract, 1994-95, GoWB

                Table-12.2(B) : Livestock Population as per 1992 Census
                                            (in ‘000)

                         Animal                  Number (‘000)             Total
                         Cross bred                      962
                         Indigenous                     16492                     17454
               Buffalo                                  1011
               Livestock                                        Year
                                   1961         1966        1972 1977                 1982    1989
                        Cross bred                           29
                        Indigenous                         1459                              1488
               Goats                                       14934
               Horses and Ponies                             13
               Donkeys                                        1
               Camel                                          0
                       Cross bred                            86
                       Indigenous                           868                              954
               Poultry                                     37408
               Source : Directorate of Economics and Statistics, Ministry of Agriculture .

12.2.1 Biomass Demand for Livestock

The pressure of livestock on grazing land could be appreciated from the
fact that the increasing size of livestock population demands a huge
amount of vegetable biomass for fodder. The pressure of this livestock on
lands for fodder has partly been a factor for degradation of forest cover
in the south western and northern districts of West Bengal. In Bankura,
Birbhum, Medinipur, Puruliya and West Bardhaman districts, cattle from
the forest-fringe villages browse in the sal coppice forests almost
throughout the year. The understory of the forest, composed of numerous
herb, shrubs, and tree sapling are thus severely damaged, affecting the
floral composition and density in the long run. Villagers in this region do
not, by and large, graze their goats in the sal forest for fear of perdition
from wolf, but both goats and cattle graze in the relatively safer
plantation plots. In order to maintain the green cover in the plantations,
the State Forest Department has, until recently, raised monocultures of
non-browsable exotics like Eucalyptus tereticornis and Acacia

No systematic data on the flow of biomass as fodder to the livestock at
the district level are available. Nevertheless, a recent study of a NGO
(School of Fundamental Research), carried out in 50 mouzas in Puruliya
District, may serve as indicative of situation of land productivity in relation
to the livestock in the district. This study estimated the quantity of fodder
biomass required to feed the enumerated cattle population in the study
area. The amount of green biomass (green leaves from trees and the
foliage of cultivated crops) as well as dry biomass (paddy straw and rice
concentrates) that is stall fed, was quantified. The overall gap between
the biomass required for the cattle and the biomass which is being
actually fed to the cattle is estimated at 31.14% of that required. These
figures have been extrapolated for the whole district and presented in

                             Table -12.2.1 : Biomass Requirement in Puruliya

                                Variables                SFR Study          Puruliya
                                                           Zone             District
                            Cultivated Area (ha)             4648.09         424480.00
                            Green Biomass reqd.             454580.4        24274593.00
                            Dry Biomass reqd. (q/y          217300.40       11603841.00
                            Green Biomass stall             174968.52        9343318.90
                            fed (q/y)
                            Dry Biomass (q/y)               193059.64       10309384.00
                              * Data from SFR Annual Report 1996-97

       It is likely that the deficit of the fodder biomass thus calculated is to some
       extent made up by the grass biomass grazed by the cattle. While the
       quantity of the grass biomass consumed by cattle is not available, it
       seems plausible that the deficit of about 31% is not reduced during the dry
       seasons when no grasses are available, and the cattle must thrive on the
       agricultural produce and leaves from the forest.

       The above data, incomplete as they are, clearly indicate that (a) the
       carrying capacity of the agricultural and forest lands is far below the
       actual need of the cattle population if they were to be stall fed; (b) in the
       absence of any pasture, or grasslands in the region, the contribution of
       the grass biomass growing in the farm fields and wastelands is likely to be
       inadequate to make up the fodder deficit as estimated above.

       The fodder requirement of the livestock components other than cattle
       was not investigated by the SFR study, but considering the fact that
       543880 goats (ca 64% of cattle population) and 144194 buffaloes (ca 25%
       of cattle population) are the major grazing population in Puruliya, the
       deficit of the fodder biomass requirement would clearly be much greater
       than what has been estimated for the cattle above.

       The paucity of data on the total fodder biomass that is actually available at the
       district level underscores the urgent need to conduct a benchmark investigation
       in all the districts of West Bengal, involving the livestock populations, their
       productivity and the productivity of agricultural land, forests and wastelands. A
       national policy of landuse regarding livestock management can be framed only
       on the basis of such benchmark studies.

12.3   Fisheries

       The state of West Bengal is endowed with a network of wetland and rivers.
       It has a coast line of about 220 km including Hugli-Matla estuary. The
       fisheries industry in the state has developed over many years gradually
       moving from traditional capture fishery practices to extensive utilisation of
       cultured fisheries technique. Out of 8875000 hectares area of the state the
       aquatic resources available for fisheries development has been
calculated in Table-12.3.

                       Table-12.3 : Available Water Areas for Fisheries
                    Type of Water Area               Extent of Area (in
                Tank / Pond                               276204.90
                Beel / Baor                                41781.65
                Reservoir                                  16738.80
                Sewage fed wet land                         4083.00
                Rivers                                    172586.36
                Canals / Creeks                            80085.71

12.3.1 Species Diversity

The recent survey of fish bio diversity in the state of West Bengal shows a
total of 172 species of freshwater fishes and 402 species of marine fishes.
Besides the fin fishes, crustaceans (prawns, shrimps, and crabs) also form
an important component of fisheries resources, both in terms of capture
and cultured fisheries. In terms of cultured fisheries, Cirrhimus mrigala
(Mrigal), Catla catla (Catla), Labio rohita (Rohu) and introduced exotic
carp species Cyprinus carpeo (American Rui), Ctemopharyngodon idella
(Grass Carp), and Hypophthalmichthys molitrix (Silver Carp) are
extensively used in the state. In addition, two exotic species, namely,
Oreachromis mossambicus and Oreochromis niloticus (commonly known
as Tilapia) have also been extensively used for cultured fisheries. As such,
the species range for the cultured fisheries remains very small and a
significant percentage of fisheries catches in the commercial market also
depend on capture fisheries from freshwater, brackish water and marine

12.3.2 Freshwater Fisheries

In the freshwater fisheries system, the water area covered has significantly
increased from 35715 hectares in 1984-85 to 95172 hectares in 1994-95
(Deptt. of Fisheries [DoF], 1995). This has been possible by accepting a
policy of increasingly utilising semi derelict and derelict water areas. Along
with the pond fisheries, more than 40000 hectares of oxbow lake areas
(beel fisheries) have been targeted for increasing utilisation and
according to the Department of Fisheries per hectare production appears
to be highest in such type of water bodies. At present about 2500
hectares is being utilised for the beel fisheries in the state.

West Bengal is recorded as having largest impounded brackish water
area (21000 hectares) in the country, and yields nearly 50 per cent of the
total prawn production of the country originating from the impounded
brackish water area of the state. At present more than 40000 hectare of
brakish water area are being utilised in the districts of Medinipur, South 24
Parganas, and North 24 Parganas for brakishwater fisheries. The
production of prawn has increased from 4677 metric tons in 1987-88 to
13222 metric tons in 1994-95.

12.3.3 Marine Fisheries

The marine fisheries have maximum potential specially along the coastal
area within the limit of territorial water. The available areas for fisheries are
at 5 different depth classes along the coast of West Bengal. The habitats
offered by the state has been increasingly utilised. This could be
evidenced from the fact that inland fisheries production has increased by
74% between 1984-85 (38400 t) to 1994-95 (669000 t) and marine fisheries
production increased by nearly 4 times. (40000 t in 1985-86 to 151000 t in

12.3.4 Seed Production

West Bengal is considered a pioneer in the production of fish seed and
currently contributes to nearly 75% of the total production of fish seeds in
the country. The augmentation of fish seed production by hatchery
development has, in an indirect way, helped in the conservation of the
resource in the natural marine system. It is estimated that between 1984-
85 & 1994-95, the quantity of fish seed produced has nearly doubled from
4,200 million units to 8,126 million units. However, the collection of prawn
seeds specially from the Hugli-Matla in the Sunderban region has been a
matter of concern in recent years. A recent study on the impact of mass
collection of prawn seeds in mangrove ecosystem of Sunderbans indicate
that for an average collection of 6.5 gm prawn seed, more than 3,000
gms of fin-fish and 4,400 gm of shellfish are wasted per net per day, which
consists of 50 different species. This quantum of wastage is leading to a
significant loss of biodiversity as a result of prawn seed collection from the
natural habitat (Report S. D. Marine, Biological Research Institute, 1996;
Tribedi, 1994).

Introduction of intensive prawn culture on one hand and mass collection
of prawn seeds from natural habitat on the other has led to some serious
impact. The production target of the brackish water prawn in coastal
areas needs to be regulated in order to sustain the fisheries operation as
also to prevent mass fatality due to periodic viral infection. The regulatory
measures along with supply of seeds through brackish water prawn
hatcheries announced in recent times (Statesman 27 April, 1997) will be a
welcome feature in the utilisation of natural resources in the state.

12.3.5 Crab Harvesting

Special mention may be made of yet another aquatic resource that is
being regularly harvested under the fishery sector. At least two species
and five species groups of crabs are regularly being caught in the
Sunderban area. The total crab fishery landing data varies between 1200
to 1500 tonnes per year. The percentage frequency distribution of crabs
caught in hook and lines show that nearly 80% of the crabs measure
between 40-80 mm when caught by hook; on the other hand, nearly 78%
of the crabs measure between 81 to 120 mm when caught in lines. The
first method (by hooks) is thus apt to affect the juveniles and consequent
regeneration of the natural population. The Fishery Policy in the state
could be effectively directed towards brackish water crab culture in
extensive lowlands and char lands. The lands which are not capable of
yielding any agricultural crop may profitably be used for crab fishery
culture. At present there is no farm / fishery exclusively meant for
cultivation of crabs in West Bengal. Crab culture is a common practice in
Taiwan, Indonesia and Philippines, specially with Scylla. The method may
be adopted from these countries.

Table-12.3.5 : Estimated Species-wise Landings of Crabs in the Sunderban
                           during 1984-85 and 1985-86

                    Crab            Estimated Landings          Estimated
                   Species              (in tonnes)            Landings (in
                                                1984-85            1985-86
                Scylla serrate                   1330               1151
                Varuna litterata                  20                 15
                Portunus spp                       1                  1
                Chanybdis spp                     60                 50
                Calappa spp                        1                  1
                Matreta spp                       30                 25
                Paratelphnsa                       1                  1
                Total                            1443               1244
              Source : Nandi & Pramanik, 1994

12.3.6 Use of Remote Sensing

The application of remote sensing technology for locating potential fishing ground
in marine sector of coastal West Bengal has been tested through validation
experiment. When the forecast for fishing ground received from Space
Application Centre (SAC), Ahmedabad, was communicated through Fishery
Department, West Bengal, to the operating fishermen, catch rates were 40%
higher than normal.

The use of remote sensing technique is a proven tool for successful fishing
operation; dissemination of information by AIR station to the coastal fishery
operators in time, suitable training for fishermen etc. and work on ocean colour
mapping, using Landsat MSS data, algal mapping, phyto plankton pigment
concentration determination etc. should be given priority along with building up of
a Geographical Information System (GIS) for sustainable fisheries operation.
Data on coastal land information mapping developed by SAC Ahmedabad could
be very useful to locate appropriate sites for brackish water fisheries
development. (Chakrabarti, 1994).
   12.3.7 Sewage Fed Fisheries

   The use of sewage water for raising fish in West Bengal deserves special
   mention. The city of Calcutta is well known for the vast wetland area on its
   eastern fringe. Earlier, the wetlands of East Calcutta had high salinity level
   and the aquatic fauna including fishes were typically of brackish water
   type. The capture fisheries of East Calcutta in the salt lake and beyond
   upto the Bidyadhari-Matla changed with man made intervention. The
   release of sewage effluents into the swamps led to a natural process of
   oxygenation. The semi treated nutrient rich effluent is now being utilised
   for fish culture.

   The area occupied by sewage fed fisheries was more than 11,000 acres in
   1945. Productivity was calculated at 3.39 quintal per acre. The vast area
   being reclaimed to admit urban use, the current sewage fed fisheries
   area has declined to less than 8000 acres. However, production per acre
   has increased to 10 quintals per year. Sewage fed fisheries therefore
   added a dimension to the wise use of wetland in peri-urban area.

   Currently 148 units of such fisheries are reportedly operating in East
   Calcutta supplying nearly 20% of fresh water carps and other species to
   the Calcutta market. Besides the East Calcutta wetland, a similar practice
   is followed in a smaller wetland area of 70 hectares in south western
   Calcutta. The sewage fed fisheries of this area became operative through
   Mudiali Fisheries Cooperative Society (MFCS). While East Calcutta sewage
   fed fisheries support about 8,000 workers, MFCS fisheries feed 250 families
   and provide basic amenities and health care.

   A note of caution can be raised at this point. While sewage fed fisheries
   could be cited as an example of a double benefit from waste recycling,
   the possible contamination of fishes with bacteria, non-biodegradable
   pesticide and heavy metals from the mixed effluent originating in the core
   city area cannot be ruled out. Source separation of effluent (domestic
   and industrial) and regular monitoring of water, sludge samples from
   fishery ponds and bioassay of fish tissues has been advocated in a recent
   report on management of East Calcutta Wetlands(1997).

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