Sewage and River fed fishing an Eco-Friendly Ecosystem and its Socio-Economic Impact: A case study of Haroa CD block, West Bengal, India

ABSTRACT: Fish culture is the most important aqua culture in West Bengal. This fish culture is based on

nutrient cycling as sewage fed. Sewage- fed fishing is growing up as eco-friendly farming system. River fed

water is used through tides of Bidyadhari river at inlet area in Sunderban region and different canals are

connected to fish pond area. Recently this type of natural aquaculture is used as commercial farming system.

Many of people are engaged into this occupation and they have benefited commercially, this beneficial farming

system has been modified by experienced farmer and modern science and technology. Fish culture is the second

occupation of the people in Haroa area; they are engaged in maximum time of a year. Local markets and

markets of Kolkata Metropolitan area depend on this inland fish farming.

INTRODUCTION: Fish being one of favourite food items of the Bengalee, fishing activities have being

carried on West Bengal from ancient time. Relief of north 24 parganas specially haroa area is plain region with

wet land and related to sundarban regions. Maximum area of Haroa was covered by mangrove forest at a time.

Waste water of Kolkata Metropolitan city is passing through different canal which are connected into

Vidyadhari river by lock gate. The canal water are mixed by Vidhydhari river which water have been getting

sufficient plankton sodium chloride and other side sewage waste water carry bio-fertilizer are used to Bheri

culture system.

Piciculture had began from 1970th period in study area. Some fishermen started this culture through their own

capability for subsistence purposes. Haroa has achieved first position on net piciculture area and net effective

piciculture among total 22 CD block of North 24 Parganas. Total amount of production and profit level get the

position in district.

Total Expenditure

(in Rs) for

piciculture

Net area available

for piciculture

(Hectare)

Net area under

effective

piciculture

(Hectare)

No. of persons

engaged in culture

in the profession

Approx annual

production in

quintal

2,52,000.00 9125 8668.61 18468 260058.3

Table-1: Main features of fisheries.

Source: District Statistical Book, North Twenty Four Parganas, 2010-11

It is the eco-friendly aquaculture system, city waste water is used as natural method and some artificial nutrients

are applied for commercial purpose and high growth of production. Fish culture is famous and popular

occupation of the study area; many people are related in this profession directly and indirectly. Recently

considerable amount of fish consumed in Kolkata Metropolitan city is produced from this system.

For the last few years investigation on sewage fed fisheries have enabled CIFRI (Central India Fisheries

Research Institute) to develop technological for judicious utilization of sewage effluent though fish culture

without any other additional nutritional inputs like feed, fertilizer commonly used in freshwater aquaculture.

LITERATURE REVIEW:

Literature indicates that aquaculture as a commercial activity has been practiced since 500BC (Bunting, S.W,

2004). Waste water fed aquaculture was initiated by Germany during the late 19the century (Prein, M.,1990).

After wards, Czechoslovakia, Poland and Soviet Union also adopted the practice of direct waste water

aquaculture in sewage treatment panels during the second half of the century (Edwards, P., 1992; Bunting, S.W.,

2004). Aquaculture was found in the literature that urban and peripheral zone of urban around Kolkata, specially

at the East Kolkata Wetland (EKW) have sustained livehoods of several thousand low income people living in

the around the wetlands and makes a significant contribution to food security and income (CGR1997;Little

D,C.et al.2002; Punch, S.et.al.,2002). The food products generated were found to be safe consumption (Roy

Chaudhuri, S.et.al.2008a). The process of waste water fed Aquaculture (Bheri) treats 2/3 of Kolkata’s soluble

waste while suppliers 2/3 of the cities fish demand (Ghosh, D., 2005; Roy, et al.,2004). The scientific

mechanism behind the conversion of waste into product (fish, vegetables) has also been investigated in detail

(Roy Chaudhuri, S.et.al.2008b). Waste water fed Aquaculture is a low coast technology of recycling the organic

residues into a potential rich food sources through as eco-friendly balance system (Jana, B.B & Santana, J.,

2005)

LOCATION OF STUDY AREA: Haroa is located at extension of latitude 220 30/ N to 22038/ N and longitude

88035/ E to 88047/ E in North 24 Parganas, West Bengal. This area is bounded by Deganga and Basirhat-II in the

north, Basirhat-I and Minakhan in the east, Bhangar-II in the south and Barasat-II in the west. Total area of

study area is 152.73 sq km or 15273 Hectare and 60% of total area covered by picicultural area. The area is

described as a sort of drowned land broken by swamps. Eight Gram Panchayats i,e. Bakjuli, Haroa, Shalipur,

Gopalpur-I, Gopalpur-II, Khasbanda,, Sonapukur, Kulti and Shankarpur and ninety villages are included in

study area.

Fig.-1 Location MapSource: Orient Longman, District Statistical Book, North 24 Parganas and Google map. METHODOLOGY:

I. To determine season income procedure of Bheri system.

II. To evaluate the production performances of fish per hectare.

III. To correlate the between fish production and eco-friendly farming.

IV. To analyse the modernization of wetland farming.

V. To measure the fish aquaculture and socio-economic pattern of study area

All methods have explained by using different primary data sources and important secondary data from District

Statistical Book, North Four Parganas, 2000-11. 80 fishermen and land owners have been randomly selected in

different mouza and have been collected data from them.

OBJECTIVE: This study has made basis on mainly primary information and some important secondary data.

Initially this type of fish culture was made and concentrated in East Kolkata wetland, after that has increased

demand of huge amount of fish which effects on extension of fish culture to eastern side of Kolkata covered by

north and south 24 parganas. This study help to how inland fishing get a vital role of fish production in state.

This type of culture has grown up by sewage and fiver fed system. But this subsistence aqua farming has been

changed due to increasing demand of fish. The farmers are using different artificial pesticide and fertilizer for

fast growing fish. Farmers, landowners and businessman are involved to this occupation directly and indirectly.

They can be achieved their betterment life style than other occupation. It is the seasonal production but

preparation of Bheri or fisheries and its related work are very important for whole year.

ECO-FRIENDLY FARMING: There is one type of inland fish culture in study area which can be explained as

eco-friendly farming system. Some important features are:-

1. Use of sewage waste materials: Firstly sewage fed is used through canals which are connected

between and Kolkata Metropolitan area. So many fisheries depend on this source of water. Dehari and

Ghosh (4979) observed sewage effluent to contain a high amount of nutritive substances which may be

utilized for productive purpose in the form of organic fertilizers. Liberated nitrogen, phosphorus and

trace elements o waste water stimulate primary productivity of ponds and primary producer

(phytoplankton) start blooming within 3-5 days of application followed by zooplankton, insects etc

(Ghosh et al; 1988). Mann (1972) recorded that smaller practices of waste acted as a directly source of

food to zooplankters and benthos while larger particle were directly used by fishes.

Sewage waste materials produced by human community hold high protentials for boosting high

production. The usual high density of plankton and consequent die-off in sewage water ponds (Bheries)

is controlled and water quality improved by stocking with fish which graze upon and utilized the dense

plankton population in such Bheri.

2. Uses of nutrient rich river water: There is a main river is Bidyadhari river which connected to

fisheries through sub canals and pond-dyke. This river water is mixed with sewage waste materials,

which is effluent into canal, sub-canal and pond dyke at the time of high tide. Necessary planktons,

sodium chloride, potassium chloride etc are mixed through river water, this mixed water is made a

faviourable condition of inlet-born fish like Tiger prawn, Giant prawn, Bhetki, Parshe, Bhangan and

Tangra etc fishes.

3. Preparation of Farming: Bheri preparation is undertaken generally in winter (Nov-Feb) when the fish

growth is reported slowest. Bheri or ponds are drained, desalted, filled and dried in the sun. Sewage

from canal is drawn to the Bheri and allowed stabilise for 15-20 days.

The liming done in this stage to the pH of the bottom soil and as well as to destroy pathogens.

Lime also helps to improve the growth of the fishes. Lime is applied in the Bheri by checking its pH. If

pH is lower than 7, then 50-80 kg of lime is often used in one bigha (1bigha=0.2532 hectare) Bheri to

improve pH.

The Bheri dykes are consolidated; silt straps (parameter canal along the dyke) 2-3 meter wide

and 30-40 cm deep are drug as the get filled during regular harvesting of fish. Fisheries or Bheri

boundary is protected from erosion by dyke.

After filling water and during the harvesting of fish, fisheries are cleaned by manually (hand

picking). There different weeds grow- up, some fishes (grass carp and silver carp) feed weeds, and grow

up fast. But it is maintained that how many amount of weeds suitable for growing fish.

For raising carp seeds, Bheri or ponds are dewatered completely during summer to remove all

the carnivorous and weed fishes, when complete dewatering is not possible treatment with mahua oil

cake (distillation residue of the fruit used natural pesticide) or other similar fish toxicants are used. The

oil cake turns the water black, but after few days the water become clear and residue of the oil cake acts

as the fertilizer. The wooden sluice gates are used to maintain the optimum level of water in Bheri.

4. Feeding of Fish: Generally are feeding of fish is not practiced in extensive and semi subsistence

sewage fed and nutrient rich river water system. But semi intensive type culture system feeding is

practiced with mustered oil cake and rice bran by 1:1 ratio; and nut oil cake, coconut oil cake, cow

dung, corn oil cake also used. The nursery Bheri fisheries are fed with wheat flower and herbivorous

fishes are fed aquatic vegetation and aquatic weeds. From last few years the waste food products like

residues of foods from restaurants, home and ceremonies and breads are used in fisheries as foods.

DATA ANALYSIS

Growth of fish: There are different type of fishes culture in study area; different carps (i.e. Catla, Rahu, Mrigal,

Silver carp, Grass carp, and Bata), Bhetki,Tiger prawn, Parshe, Tangra etc are produced here. Growth rate of

fishes are divided into four periods of a season- less than 3 months, 3-6 months, 6-9 months, more than 9

months.

Growth rate of fishes are maximum increased after six months, at this time standard size of fish are

supplied to the local wholesale market (arat).

SL NoNAME OF FISH

GROWTH OF FISHES

< 3 MONTH (in gm)

3-6 MONTH (in gm)

6-9 MONTH (in gm)

> 9 MONTH (in gm)

1. Catla 200-300 400-700 700-1500 1500-20002. Rohu 150-200 300-500 600-800 800-10003. Mrigal 100-150 200-300 400-800 800-10004. Bata 50-100 100-150 150-200 200-3005. Bhetki 250-300 300-600 600-1000 1500-20006. Tiger prawn 10-20 20-30 30-40 40-507. Giant prawn (Galda) 15-25 25-30 50-75 75-1008. Parshe 50-100 100-150 150-200 200-2509. Bhangan 100-150 150-250 250-500 500-80010. Tangra 10-20 20-30 30-40 50-8011. Grass carp 200-400 400-600 600-1000 1000-150012. Silver acrp 200-300 300-400 400-800 1000-150013. Calbose 100-200 200-400 400-800 800-100014. Tilapia/ Nilontica 50-100 100-150 150-200 200-250

Table-2 Fish growth rate at different periods of a session

Source: Primary data, survey on 23-27th January, 2018

< 3 Months 3-6Months 6-9 Months > 9 Months 0

200400600800

100012001400160018002000

CatlaRohuMrigalBata

INDEX

GROWTH RATE OF DIFFERENT FISHW

EIG

HT

IN G

RA

M

Fig.-2. Growth rate of different major carp. (as per primary data, Table No.-2)

< 3 Months

3-6Months 6-9 Months

> 9 Months

0

200

400

600

800

1000

1200

1400

Grass carp

Silver carp

Calbose

Tilapia/ Nilon-tica

INDEX

GROWTH RATE OF DIFFERENT FISH

WEI

GHT

IN G

RAM

Fig.-3. Growth rate of different carp and other fish (as per primary data, Table No.-2)

< 3 Months 3-6Months 6-9 Months

> 9 Months 0

200

400

600

800

1000

1200

1400

1600

1800

2000

Bhetki

Tiger prawn

Giant prawn (Galda)

Parshe

Tangra

Bhangan

GROWTH RATE OF DIFFERENT FISH

INDEX

WE

IGH

T IN

GR

AM

Fig.-4. Growth rate of inlet born fish (as per primary data Table No.-2)

As per collected primary data and observation of wholesale market and fisheries; different fishes are divided

into three categories. Firstly major carps are cultured in specific fisheries; these fishes are very demanding at

market i.e. Catla, Rahu, Mrigal, Bata. Comparatively growth rate of Catla is better than other fishes and growth

rate of Bata is very slow than other carp due to its genetic characteristics.

Secondly some carps, Tilapia and Nilontika are cultured in fisheries. Growth rate of Grass carp and

Silver carps is better than other fish and these types of carps purely under herbivorus species. They are growth

rate is better than other carps, get foods from natural weeds and grass of fisheries. Tilapia and Nilontika which

growth rate is comparatively slow due to genetic causes.

Thirdly inlet born fish i.e. Bhetki, Tigerprawn, Tangra, Parshe, Bhangan which are cultured in fisheries

to made faviourable condition for fast growing. The high growth rate fish is Bhetki which fish is under

carnivorous category. Tiger prawn, Giant prawn, Parshe, which growth rate comparatively low due to genetic

causes. Generally different carps and inlet born fishes are practied separately for getting high production.

Labour and Expenditure: Bheri aquaculture is one of the most important profession of local people in study

area. Maximum fishermen, who are 77 % of total fishermen, have taken bheri as lease from landowners. They

are doing this job professionally and only 23% of fishermen do fish practice in their own fisheries. They take

risk factors and get income from directly engagement.

23%

77%

OWNERSHIP OF FISHERIES

OWNED

LEASE

INDEX

Fig.-5 Status of ownership of fisheries. (as per primary data, Table No. -4)

Different types of labours are engaged in aquaculture. Two types of guards (guard in ala and guard by boat),

fisherman (who catch fish in fisheries), fish supplier (from Bheri to wholesale market), sluice gate maintainers,

labours are engaged in Bheri preparation, Sluice gate maintainers, fish seeds suppliers and Golders, food

suppliers and fish collector from fisheries etc.

Sl No Expenditure in different purpose Amount (in Rs.)1. Ala guard per month 4000.002. Guard by floating boat per month 5500.003. Labour as fish catcher per day 170.004. Fish collector from fisheries @ 2% of total fish Depend on amount of fish5. Sluice gate maintainer per day 250.006. Labour for giving feed, fertilizer and pesticide 250.00

Table-3: Expenditure during fish culture. Source: Primary data, survey on 23-27th January, 2018

Maximum labours and employees are temporarily and contractual basis. They do their work as per day

or per month basis. But these types of labour are necessary at all time a year, their roles are very vital to produce

sufficient fish. Maximum costing of any type of labour is near about Rs. 10,000/- per month. Labours also get

some extra benefits and get fish from fisheries for their family daily food demand.

Profession and Improvements: Firstly aquaculture was characterised as an extensive farming system. Now it

has converted into intensive and semi subsistence farming system. So fishermen have already experienced,

apply fertilizers and pesticides for fast growing fish. But till now, they do not any test of water through scientific

way. Sometime fishermen face critical biotic hazards through bacteria and virus, maximum fishes are affected.

Some experience fishermen deal this situation through technical process and precautions. They think that risk

factors of fishing have been decreased by input of modern science and technology. Now a day’s different

modern pesticide are used, keorine is the most important pesticide which save fish from harmful bacteria and

virus. Fishermen are also used some biotic and chemical fertilizer for fast growing fish.

Sl No. Subjects Types Respondents in %

1.Working experience of a fisherman

< 5 Year 195-10 Year 6510-15 Year 12> 15 Year 4

2.Ownership of fisheries Own 23

Lease 77

3.Amount of fisheries per fisherman

< 5 Hectare 775-10 Hectare 19>10 Hectare 4

4.Income (in Rs.)from per Bigha or .25 Hectare

< 1 Lac 121-1.5 Lacs 60> 1.5 Lacs 28

Table-4: Different characteristics of fisheries and fishermen.

Source: Primary data, survey on 23-27th January, 2018

< 5 Years 5-10 Years 10-15 Years

>15 Years0%

10%

20%

30%

40%

50%

60%

70%

Series1

WORKING EXPERIENCE OF FISHERMEN

INDEX

RE

SPO

ND

EN

TS

Fig.-6 Working experience of fishermen (as per primary data, Table No. -4))

In study area, there are maximum fishermen (65%) have been doing this job from 5-10 years and 10-15 years

experienced fishermen are 12% and 4% fishermen belong in most experienced category, they have been doing

this profession from 15 years ago. New comers of this profession are only 19% who have engaged in

aquaculture not more than 5 years.

77%

19%4%

PER HEAD FISHERIES OF FIGHERMEN

< 5 Hectare5-10 Hectare> 10 Hectare

INDEX

Fig.-7 Amount of fisheries of per head fisherman (as per primary data, Table No. -4)

The rich fishermen are only 4%, they have more than 10 hectare fisheries per head and 77% of total

fishermen have near 5 hectare fisheries and rest of fishermen culture 5-10 hectare fisheries per head.

Wholesale Markets and Supplied Area: Fish are supplied to nearest wholesale market, some labours who are

collected fish from different fisheries or bheri and supplied to nearest wholesale market (arat), they are got near

about 2% commission of total amount of fish from wholesaler. Main wholesale markets of study area are

Malacha, Ghusighata, Haroa, Matia, Gorerdanga, Louhati, Kharibari. From June to December is the best season

of fish supply to wholesale market, after December fish supply is decreased owing to dewatered of maximum

fisheries. Rate of fish at wholesale market are varied not only on supply of fish and size of fish but also depends

on demand of township markets.

Sl No Name of Fish Selling rate of fish per Kg.2016 2017

1. Catla 180-220 200-2502. Rohu 100-120 120-1303. Mrigal 90-110 110-1204. Bata 80-100 100-1205. Bhetki 250-350 300-4006. Tiger prawn 500-600 500-7007. Giant prawn (Galda) 400-500 400-6008. Parshe 150-250 200-3009. Bhangan 150-200 150-25010. Tangra 300-350 300-40011. Grass carp 80-90 80-10012. Silver acrp 70-90 80-10013. Calbose 120-130 130-15014. Tilapia/ Nilontica 80-100 90-100

Table-5: Fish rate of wholesale market in 2016 and 2017.

Source: Primary data, survey on 29th and 30th January, 2018 at Malancha and Haroa wholesale market.

0100200300400500600700

20162017

INDEX

SELLING RATE OF FISH AT WHOLSALE MARKETSIN

RS.

Fig.-8: Fish rate of wholesale market in last two years (as per primary data Table No.-5)

Rate of fish at wholesale market has been changed between last two years. The markets price of 2017 is

higher than of 2016. Some of fish comparatively Bhetki, Tiger prawn, Giant prawn, Parshe, Tangra are very

demanding fish than other.

Calculation of Co-efficient of variation for 2016

C . V= SDMean

×100

C . V=143.61205

×100

=70%

Calculation of Co-efficient of variation for 2016

C . V= SDMean

×100

C . V=156.77231.14

×100

=67.82%

From last several years, fish rate has been increased, but all of have not been increased as same rate.

Here, in 2016 variation rate of among fishes is 70% and in the last year wholesale rate among the fishes is

67.82%. Actually high rate of fishes at wholesale market has been increased but low rate fish comparatively

more increased in last year.

These natural and artificial wetland areas take an important role to supply fish at different markets of

Kolkata Metropolitan area. Most part of north and south Kolkata i.e. Sonarpur, Garia, Bakhajatin, Kasba,

Sealdah, Dum Dum, Barasat, Madhyamgram, New Barrackpore, Rajarhat, Saltlake are most beneficial area.

Fresh fish are supplied to these areas at morning and evening market on every day.

Economic Condition: Recently this occupation has signed as the most profitable profession. Maximum of

fishermen gain sufficient profit than other occupation, they could have changed their lifestyle as rich man in the

area. As per survey, the lease holders, landowners and wholesaler could have achieved earning amount than

other persons who are engaged fish culture directly and indirectly.

< 1 Lac 1-1.5 Lacs

> 1.5 Lacs

0%10%20%30%40%50%60%70%

INCOME FROM PER BIGHA FISHERY

Series1

INCOME IN RS.

RE

SPO

ND

EN

TS

INDEX

Fig.-9: Yearly income from per bigha of fishery (as per primary data Table No.-4)

Basis of fishermen opinion profit of this profession is varied on production rate, supply and

demand on markets, different occasions. Maximum of fishermen who are 60 % of total fishermen get profit

Rs.1-1.5 lacs per bigha or .4 hectare of a year. 28% of fishermen have earned more than Rs. 1.5 lacs per bigha

or .25 hectare of a year and least amount of fishermen (12%) have earned last year almost Rs 1 lac per bigha.

MAJOR FINDINGS:

1. Mainly this is seasonal aquaculture but off season is important for preparation of Bheri system.

2. Profit level may be changed due to lack scientific application and untrained labour.

3. Fishermen face different social (stealing of fish, conflict with other fisherman) and political hazards as

results they expense extra money for avoiding.

4. Fish cultures have been changed from last 10 years due to huge demand of fish, the fishermen have

inputs the characteristics of intensive farming.

5. Recently chemical mixed sewage water is damaging fish culture mainly different prawns are affected

by polluted sewage water.

6. In winter season, water crises are main problem of this area. Density of polluted water is increased in

this period.

SUGGESTIONS: For improvement of production and productivity of fisheries (Bheri), as well as over all

condition of the fishermen, the following suggestions are put forward:-

1. For better production of fish, all fishermen should be formed a society where will be mainly discussed

about different problems of fish production and they will be taken the best solution from discussion.

2. Fishermen may be encouraged to set up aqua club or society that may facilitate developing awareness

about different fisheries activities like importance of sees collection, proper stocking, control of

predatory, improvement of organic manure, proper management of fish culture.

3. Necessity of some sub-canals which will be connected to Bagjola canal can be given sufficient nutrients

rich waste water to all fisheries.

4. Some agencies should be taken a role to supply high quality of fish seeds and fishermen must be trained

by efficient government or private institutions.

5. There should be proper storage and processing facilities in fish landing centres and need some agencies

who will buy fish from fisheries.

6. Government should to develop proper marketing facilities and to provide administrative set up.

CONCLUSION: Sewage fed and river fed fishing is mainly eco- friendly fishing, although last two decade

this subsistence fish culture has been changed due to huge demand in Kolkata Metropolitan area. The

fishermen had cultured fisheries only for primary demands but recently this production has taken a vital role

for supplying demanded fish at nearest area as commercial purpose. As result the socio- economic pattern

has been changed of fisherman, they have improved their life style. Some of important fish are transported

for exporting to national level and international level also.

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