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Aquaculture production
systems in intertidal areas of
Bangladesh: a review
Md. Jahangir Alam
Bangabandhu Sheikh Mujibur Ra...
Contents	
  
Introduction	
  ................................................................................................
Brackishwater	
  aquaculture:	
  historical	
  
development	
  
•  Farming of shrimp, which is believed to have started in...
Brackishwater	
  aquaculture:	
  historical	
  
development	
  
•  Controlled shrimp (P. monodon) farming within
polders w...
•  In 1979-80, about 19,500 ha of coastal land were under
bagda (P. monodon) and 3,500 ha under golda (M.
rosenbergii) cul...
•  Shrimp farming is majorly in four coastal districts
•  74% in Khulna region
	
  Brackishwater	
  aquaculture:	
  histor...
•  Farm ownership by absentee operators in larger
ghers (11-37 ha) was common earlier.
•  Presently most of the farms (80%...
•  Shrimp (both bagda and golda) production increased over the
period
•  The output growth in shrimp production up to 1990...
•  Golda production share is increasing
•  Production (incidental) of M. monoceros in also increasing
•  Finfish productio...
Shrimp cropping
pattern
Months
J F M A M J J A S O N D
Satkhira
Year-round bagda
Bagda-rice rotation
Khulna
Bagda-rice rot...
 
	
  Shrimp	
  aquaculture	
  produc*on	
  
systems	
  
	
  
	
  	
  	
  	
  
	
  	
   SHRIMP	
  CULTURE	
  SYSTEM
Tradi*...
 
	
  Shrimp-­‐rice	
  produc*on	
  system	
  
	
  
Modified	
  ader	
  DaLa,	
  2001	
  
 Dry	
  season	
  shrimp	
  culture	
  management	
  in	
  
shrimp-­‐rice	
  system	
  
	
  
Management	
  measures	
   Pr...
Management	
  measures	
   Produc?on	
   Authors	
  
Prepara?on	
   Stocking	
  	
   Grow-­‐out	
   Survival	
  rate	
  (%...
 Dry	
  season	
  shrimp	
  culture	
  management	
  in	
  
shrimp-­‐rice	
  system	
  
	
  Management	
  measures	
   Pro...
 
	
  Wet	
  season	
  rice	
  cul*va*on	
  
	
  •  Jotabalam, Ghunshi, Hokoz - local varieties mostly
cultivated in the s...
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Wet seasonDry season
Gher
preparation
•  Water depth- 60-80 cm
•  Single s...
68,337a	
  
48,908b	
  
43,160b	
  
Control	
  
11.69	
  
0	
  
10	
  
20	
  
30	
  
40	
  
50	
  
60	
  
70	
  
80	
  
90...
Characteristics of different shrimp production systems that
are presently being practiced in south-west region of
Banglade...
Freshwater prawn (M. rosenbergii)
farming
•  Prawn aquaculture, which is widely adopted in Bagerhat
and Khulna districts.
...
Freshwater prawn (M. rosenbergii)
farming
•  Prawn aquaculture, which is widely adopted in Bagerhat
and Khulna districts.
...
•  Techniques available for increased production by adoption
of improved to semi-intensive farming system
•  Approximately...
Species diversification in shrimp farming
•  Success in captive breeding and seed
production of Mystus gulio, locally call...
Environmental impact of shrimp farming
Two major
environmental
issues: are
addressed:
clearing of
mangroves for
farm
devel...
Environmental impact of shrimp farming
•  Degraded soil qualities due to 5-15 years of
continuous shrimp farming in the ar...
Social impact of shrimp farming
•  Literature available on social issues highlighting negative
social consequences : land ...
Social impact of shrimp farming
•  With the gradual but widespread increase in owner
occupation, reduction in gher size an...
Sectorial linkage and livelihoods
(Alauddin	
  and	
  Hamid,	
  1998).	
  
More than 600,000 people iengaged in activities...
Conclusion
•  The future development challenge in brackishwater
aquaculture should focus on :
•  Multidisciplinary empiric...
Conclusion
•  Improvement of land-water management system
are of prime importance to setting R&D strategies.
•  Supply and...
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Aquaculture production systems in intertidal areas of Bangladesh: A review

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By Md. Jahangir Alam

Revitalizing the Ganges Coastal Zone Conference
21-23 October 2014, Dhaka, Bangladesh
http://waterandfood.org/ganges-conference/

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Aquaculture production systems in intertidal areas of Bangladesh: A review

  1. 1. Aquaculture production systems in intertidal areas of Bangladesh: a review Md. Jahangir Alam Bangabandhu Sheikh Mujibur Rahman Agricultural University Gazipur-1706, Bangladesh
  2. 2. Contents   Introduction  ..................................................................................................................................................  4   Importance  of  brackishwater  aquaculture  ...............................................................................................  4   Aquacultures  contribution  to  livelihoods  .................................................................................................  8   Historical  development  of  brackishwater  shrimp  farming  in  Bangladesh  ..................................................  10   Main  shrimp  farming  areas  .....................................................................................................................  10   Ownership  of  shrimp  farms  ....................................................................................................................  11   Historical  development  of  shrimp  production  ........................................................................................  11   Brackishwater  aquaculture  practice  ...........................................................................................................  13   Cropping  pattern  in  brackishwater  aquaculture  .....................................................................................  13   Shrimp  aquaculture  systems  in  the  coastal  zone  ....................................................................................  14   Rice-­‐based  shrimp  farming  .........................................................................................................................  16   The  change  from  rice  to  shrimp  ..............................................................................................................  16   Climatic  and  hydrological  suitability  for  rice-­‐shrimp  system  ..................................................................  17   Shrimp  farming  in  rotation  with  paddy  ...................................................................................................  18   Pre-­‐stocking  management  ......................................................................................................................  19   Stocking  of  shrimp  in  rice-­‐shrimp  systems  .............................................................................................  20   Water  quality  ..........................................................................................................................................  21   Fertilization  of  ghers  ...............................................................................................................................  21   Shrimp  aquaculture  feeds  .......................................................................................................................  22   Health  and  disease  management  ...........................................................................................................  23   Production  and  economics  of  shrimp  aquaculture  .....................................................................................  24   Wet  season  rice  cultivation  .........................................................................................................................  29   Rice  varieties  and  production  .................................................................................................................  29   Water  and  nutrient  management  ...........................................................................................................  30   Integration  of  aquaculture  with  wet-­‐season  rice  cultivation  in  rice-­‐shrimp  system  ..............................  31   Environmental  impact  of  shrimp  farming  ...................................................................................................  32   Social  impact  of  shrimp  farming  .................................................................................................................  35   Opportunities  for  increasing  brackishwater  aquaculture  productivity  and  profitability............................  37   Semi-­‐intensive  shrimp  farming  ...............................................................................................................  38                  iversifica*on  in  brackishwatr  aquaculture  …………-­‐………………………………………………………………………………………………………………..39            Conclusion  ………………………………………………………………………………………………………………………………………………………………………………  40      References  …………………………………………………………………………………………………………………………………………………………………………………42  
  3. 3. Brackishwater  aquaculture:  historical   development   •  Farming of shrimp, which is believed to have started in 1829 in the southwest Sundarbans mangrove area (Paul, 1995), •  An age-old practice in the coastal areas of Bangladesh involving the most traditional way of trapping-holding- growing shrimp in polyculture with shellfish and finfish species in tidal and low-lying areas isolated by dykes (locally called “bheri”). •  Polderization started from early 60s brought an end to traditional shrimp trapping and holding systems in these areas (Paul, 1995, Williams, et al., 2003)
  4. 4. Brackishwater  aquaculture:  historical   development   •  Controlled shrimp (P. monodon) farming within polders was resumed in early 70s in polders within the embanked areas (Akhtaruszzaman, et al., 1985). •  Economic importance of shrimp and unviability of rice production together provided a catalyst for an accelerated development of shrimp farming within the polders, •  FW prawn (M. rosenbergii) farming started in early 80s (Abedin et al., 2001). •  Shrimp farming was declared as industry in the 2nd FYP (1980-85).
  5. 5. •  In 1979-80, about 19,500 ha of coastal land were under bagda (P. monodon) and 3,500 ha under golda (M. rosenbergii) cultivation (Ahmed, 1988). •  BW aquaculture farming area expanded rapidly (DoF, 2011) •  162% from 1984 to 1997 •  3.19%, from 1997 to 2002 •  58.86% from 2002 to 2010 Brackishwater aquaculture: historical development 20   87   108   138   141   141   203   217   217   246   276   0   50   100   150   200   250   300   Farm  area  (x000)ha)     Financial  Year   107962   202576   29792   65200   0   50000   100000   150000   200000   250000   Area  (ha)   Khulna  Division   ChiLagong  Division   79% shrimp and 21% golda
  6. 6. •  Shrimp farming is majorly in four coastal districts •  74% in Khulna region  Brackishwater  aquaculture:  historical   development     Districts   Shrimp  farming  area    (ha)  10-­‐11   Bagda   Golda   Total   Bagerhat   47900   18556   66456   Khulna   35557   13960   50517   Satkhira   60348   7664   68012   Barguna   108   179   287   Barishal   00   686   686   Patuakhali   2478   1733   4211   Pirojpur   420   1440   1860   Cox’s Bazar   62907   00   62907   Khulna,   202576,   74%   Barishal,   7128,  2%   ChiLagon g,  65200,   24%   Costal  division-­‐wise  shrimp/prawn    farm  area  (ha)  (2010-­‐11)  
  7. 7. •  Farm ownership by absentee operators in larger ghers (11-37 ha) was common earlier. •  Presently most of the farms (80%) are operated by the landowners. •  Farm size has been reduced gradually over the years to an average of 8-10 ha.    Brackishwater  aquaculture:  historical   development  
  8. 8. •  Shrimp (both bagda and golda) production increased over the period •  The output growth in shrimp production up to 1990s was mainly the result of the expansion of the farm area. •  Per ha bagda and golda procuction production averaged approximately 245 and 500 kg/ha, respectively in 2008-09    Brackishwater  aquaculture:  historical   development  14.773   17.889   18.235   18.624   19.489   20.335   23.53   28.302   34.03   46.223   52.272   62.167   63.164   64.647   64.97   65.579   66.703   75.167   82.661   85.51   86.84   94.211   102.854   87.972   124.648   0   20   40   60   80   100   120   140   Produc?on  (x1000  mt)   Financial  Year  
  9. 9. •  Golda production share is increasing •  Production (incidental) of M. monoceros in also increasing •  Finfish production increased from 47839 mt (2008-09) to 60290 mt (2010-11)  Brackishwater  aquaculture:  historical   development   Bagda  (P.   monodon)   51%   Golda  (M.   rosenbergii)   27%   Harina  (M.   monoceros)   12%   Chaka  (P.   indicus)   2%   Other  shrimp/ prawn   8%   Bagda  (P.   monodon)   45%   Golda  (M.   rosenbergii)   32%   Harina  (M.   monoceros)   14%   Chaka  (P.   indicus)   2%   Other  shrimp/ prawn   7%   2008-­‐09   2010-­‐11  
  10. 10. Shrimp cropping pattern Months J F M A M J J A S O N D Satkhira Year-round bagda Bagda-rice rotation Khulna Bagda-rice rotation Golda-rice integration Bagerhat Bagda-rice rotation Golda-rice integration Cox’s Bazar Year-round bagda Bagda-salt rotation   Legend: Bagda Rice Golda-fish Salt      Brackishwater  aquaculture  prac*ces    
  11. 11.    Shrimp  aquaculture  produc*on   systems                 SHRIMP  CULTURE  SYSTEM Tradi*onal  extensive  (85%) Semi-­‐intensive No  Prepara*on No  fer*liza*on Mostly  naturally  trapped  seed     PRODUCTION  LEVEL Improved  extensive  (14%)     Prepara*on Fer*liza*on External seed stocking Prepara*on Fer*liza*on External  seed  stocking Feeding  (inconsistent) Water  management Prepara*on  &  fer*liza*on External  seed  stocking Formulated  feeding Closed  system  water   management Aera)on Low  yield 50-­‐250  kg/ha Medium  yield:  250-­‐750  kg/ha High  yield 1000-­‐2500  kg/ha
  12. 12.    Shrimp-­‐rice  produc*on  system     Modified  ader  DaLa,  2001  
  13. 13.  Dry  season  shrimp  culture  management  in   shrimp-­‐rice  system     Management  measures   Produc?on   Authors   Prepara?on   Stocking     Grow-­‐out   Survival   rate  (%)   Yield  rate   (kg/ha)       •  Pond  drying  and  ploughing     •  Liming  ()  depending  on  soil  pH   •  Fer?liza?on:  cow  dung  @  500kg/ha;  MOC   @  100  kg/ha;  TSP-­‐urea  &  35  kg/ha  (3:1   ra?o)       •  2.0  -­‐  2.5/m2   •  Single   stocking     •  Water  depth  40-­‐100  cm   •  Water  exchange  during  new   and  full  moon   •  Fer*liza*on  with  urea  and   TSP  ()  depending  natural   food  availability.   •  No  feeding     39  -­‐  41   231  -­‐  299   Roy  et  al.   (1999)   •  Pond  drying  and    ploughing   •  Liming  ()  depending  on  soil  pH   •  Fer?liza?on:  cow  dung  @  500kg/ha;  MOC   @  100  kg/ha;  TSP-­‐urea  &  35  kg/ha  (3:1   ra?o)       •  1.5-­‐1.75/ m2   •  Treated  in   100  ppm   formalin   solu*on  for   30  minutes   •  Single   stocking     •  Water  depth  1-­‐1.2  m   •  Water  exchange  during  new   and  full  moon   •  Fer*liza*on  @  15  kg/ha   (TSP:Urea=3:1)  ader  each   water  exchange   •  Liming  with  CaCO3  @   150-­‐250  kg/ha,  as  and  when   required   49  -­‐  58   334  -­‐  448   Ahmed  et   al.  (1999)   •  Pond  drying  and  ploughing   •  Applica?on  of  liquid  insec?cides   (thiodan)  at  the  first  water  intake   •  Liming  @  67-­‐82  kg/ha   •  Fer?liza?on:  cow  dung  @  700-­‐1000  kg/ ha;  MOC  @  35-­‐45  kg/ha;  TSP  @  30-­‐55   kg/ha;  urea  15-­‐20  kg/ha;  DAP  @  30-­‐55   kg/ha   •  1.4  –  2.0/ m2   •  Mul*ple   stocking     •  Water  exchange  every  4-­‐6   days  at  every  lunar  cycle   •  No  fer*liza*on  and  feeding       24  -­‐  25   146  -­‐  153   Alam  and   Phillips   (2004)  
  14. 14. Management  measures   Produc?on   Authors   Prepara?on   Stocking     Grow-­‐out   Survival  rate  (%)   Yield  rate  (kg/ ha)       •  Pond  drying  and  ploughing   •  Liming  with  dolomite  @  200-­‐250  kg/ha   •  Fer?liza?on:  urea:TSP  (1:1)    @  100  kg/ha       •  1.8  –  2.2/ m2   •  Single   stocking     •  water  depth     •  Water  exchange  at  every   lunar  cycle   •  Irregular  inorganic   fer*liza*on  and  feeding   with  rice  bran  in  smaller   (2.32  ha)  and  medium  (6.13   ha)  ghers   •  No  fer*liza*on  in  larger   (54.24  ha)  ghers       •  Smaller  ghers:   37-­‐  71   •  Medium  gher:   35-­‐39   •  Larger  ghers:   7-­‐24   •  Smaller   ghers:   164-­‐277   •  Medium   gher:   155-­‐164   •  Larger   ghers:   29-­‐121   Islam  et  al.   (2005)     Milstein  et  al.   (2005)   •  Pond  drying   •  Liming  with  CaCO3  @  250  kg/ha   •  Applica?on  of  Fostoxin  (1  tb/210c2  at  first   water  intake   •  Fer?liza?on  with  TSP  and  urea  (2:1)  @  35   kg/ha         •  2.6  -­‐  3.6/ m2   •  Single   stocking       •  Water  depth  83-­‐95  cm.   •  Applica*on  of  lime  @  50   kg/ha,  as  required   •  Fer*liza*on  with  TSP  and   urea  (2:1)  @  30  kg/ha,  as   required     •  Feeding  with  prepared   diets       63-­‐74   400-­‐533   Islam  and   Alam  (2008)   •  Peripheral  canal    of  1.5  m  depth   •  Pond  drying   •  Liming  with  CaO  @  250  kg/ha   •  Applica?on  of  Fostoxin  (1  tb/20t  of  water)   at  first  water  intake   •  Fer?liza?on  with  urea  @  1  ppm;  TSP  @  2   ppm  and  MP  &  0.5  ppm       •  3.0/m2   •  Single   stocking     •  Water  depth  31-­‐44  cm   •  Water  exchange  as   required   •  Applica*on  of  0.6-­‐0.8  ppm   dolomite  at  every  12  days   •  Applica*on  of  urea  @   0.5-­‐1.0  ppm,  TSP  @  1.0-­‐1.2   ppm  and  MP  @  0.3-­‐0.4   ppmFeeding  with  prepared   diets       25  32   168-­‐226   Islam  et  al.   (2009)  
  15. 15.  Dry  season  shrimp  culture  management  in   shrimp-­‐rice  system    Management  measures   Produc?on   Authors   Prepara?on   Stocking     Grow-­‐out   Survival   rate  (%)   Yield  rate  (kg/ ha)       •  Drying     •  Liming   with   CaO   @   250   kg/ha   •  Bleaching(@  25  ppm)  at   first  water  intake   •  Fer?liza?on:  TSP  @  3   ppm  and    urea  @  2.5   ppm       •  3.0  –  5.0/  m2   •  Single  and   double   stocking     •  Water  depth  45-­‐80  cm   •  No  regular  water  exchange,   but  replenishment  of  any  loss   •  Applica*on  of  7-­‐8  ppm   dolomite,  1.25  ppm  urea  and   1.5  ppm  TSP  at  every  15  days   interval   •  Feeding  with  commercial  diet       27-­‐36   162-­‐584   Alam  et  al.   (2010)   •  Pond  drying   •  Liming  with  CaCO3  @  250   kg/ha   •  Applica?on   of   Fostoxin   (1  tb/210c2  at  first  water   intake   •  Fer?liza?on   with   TSP   and  urea  (2:1)  @  35  kg/ ha     •      •  3.0/  m2   •  Single  stocking   •  Water  depth  83-­‐95  cm.   •  Applica*on  of  agricultural   lime  @  250  kg/ha  ader  every   raining   •  Fer*liza*on  with  TSP  and  urea   (2:1)  @  30  kg/ha,  as  required     •  Zeolite  gold  @  50  kg/ha  and   Gasonex  @  0.5  kg/ha   •  Feeding  with  prepared  diets       58-­‐73   417  –  615   Islam  and   Mahmud   (2010)  
  16. 16.    Wet  season  rice  cul*va*on    •  Jotabalam, Ghunshi, Hokoz - local varieties mostly cultivated in the shrimp farms. •  Yield varies from 1-2 t/ha •  Under the CP#10 project HYVs viz., BR-23, BRRIdhan-40, BRRIdhan-41 yielded 4-5 t/ha •  Not much nutrient application. However, in shrimp- based rice farming, application of urea (N) at the rate of 75 kg and TSP (P) 37.5 kg/ha after 24 and 60 days of transplanting respectively, has been recommended. •  Under CP#10 project, the benefit of integrating aquaculture with rice cultivation has been demonstrated.
  17. 17. Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Wet seasonDry season Gher preparation •  Water depth- 60-80 cm •  Single stocking: @ 3-5/m² •  Yield: 350-550 kg/ha •  NR: 0.75-1.00 lakh/ha (1:1.9) Golda   GIFT 5,000-10,000/ha at 1:1 ratio Yield: •  Rice: 4-5 t/ha. •  Fish: 200-250 kg/ha •  Prawn: 70-90 kg/ha Seedling Bagda   Rice   Improved rice (aman)-shrimp system HYVs: BR 23/40/41
  18. 18. 68,337a   48,908b   43,160b   Control   11.69   0   10   20   30   40   50   60   70   80   90   June   July   August   Net  return  ('ooo  Tk./ha)     Prawn  stocking  ?me   Prawn   GIFT   Rice   37.90 45.50 67.50 13.29b 23.30a24.64a 0 20 40 60 80 100 120 140 RG RGP RP SS DS3/2 DS2/3 Culture treatments Netprofit(,000Tk./ha) AC Dry season shrimp Improved rice (aman)-shrimp system •  Advancing the stocking of prawn can provide farm net returns of about 300% higher than is the case with the wet season rice crop that was currently practiced
  19. 19. Characteristics of different shrimp production systems that are presently being practiced in south-west region of Bangladesh (Adapted from Joffre et al., 2010) Framing Characteristics Shrimp monoculture Rice and shrimp rotation Rice- aquaculture and shrimp rotation Extensive Semi- intensive Pond size (ha) 1-40 1-2 1-5 1-5 Mean stocking rate (ind/m2) 1-3 5-15 1-3 1-3 Input use Lime, fertilizer Pellet feeds, water treatment Lime, fertilizer Lime, fertilizer Yield (kg/ha) 10-380 (av. 242) 49-2067 (av. 1058) Rice: 1000-3000 Shrimp: 73-268(av. 160) Rice: 1000-3000 Fish: 10-50 Shrimp: 73-268 (av. 160)
  20. 20. Freshwater prawn (M. rosenbergii) farming •  Prawn aquaculture, which is widely adopted in Bagerhat and Khulna districts. •  Spreading to other south and central coastal zones namely Jessore, Patuakhali and greater Noakhali districts (Abedin et al., 2000). •  Mostly practiced in an integrated manner with filter-feeding carps, paddy and growing of vegetables on the pond dyke. •  Integrated prawn-rice-fish-vegetables cycle begins in May/ June, with stocking of prawn PL and fish fingerlings, followed by planting of boro rice in January (Williums and Khan, 2001; Azad et al., 2005).
  21. 21. Freshwater prawn (M. rosenbergii) farming •  Prawn aquaculture, which is widely adopted in Bagerhat and Khulna districts. •  Spreading to other south and central coastal zones namely Jessore, Patuakhali and greater Noakhali districts (Abedin et al., 2000). •  Mostly practiced in an integrated manner with filter-feeding carps, paddy and growing of vegetables on the pond dyke. •  Integrated prawn-rice-fish-vegetables cycle begins in May/ June, with stocking of prawn PL and fish fingerlings, followed by planting of boro rice in January (Williums and Khan, 2001; Azad et al., 2005).
  22. 22. •  Techniques available for increased production by adoption of improved to semi-intensive farming system •  Approximately 20,000 ha are suitable for semi-intensive farming (BFFEA , 2001) Modified closed system (Saha et al. 2006-07) •  Stocking density 9-15/sqm; yield rate of 1250 – 1885 kg/ha with FCR 1.4-1.6 and net return of Tk. 0.2 million/cycle Modified improved culture •  Stocking density 5-9/sqm; yield rate 670-759 kg/ha with 2.15-2.4 and net return Tk. 0.07 – 0.15 million (Laif and Alam, 2008) •  Stocking density 5/sqm; yield rate 667-811 kg/ha (Saha et al., 2008) Opportuni*es  for  increased  produc*vity    
  23. 23. Species diversification in shrimp farming •  Success in captive breeding and seed production of Mystus gulio, locally called “nona tengra” (Alam et al., 2006; Alam et al., 2007b). •  Shrimp-tilapia (GIFT/monosex) mixed and/or rotational (Alam et al., 2008; Saha et al., 2009) •  Shrimp-Pangas-tilapia polyculture (BFRI, 2007) •  Shrimp-mud crab biculture (Momtaz et al., 2007; Momtaz et al., 2010) Opportuni*es  for  increased  produc*vity  
  24. 24. Environmental impact of shrimp farming Two major environmental issues: are addressed: clearing of mangroves for farm development and coastal land degradation due to salinization. Area Location Total area of mangrove (ha) Total loss (ha)1975 1983 1999 South-west SRF 600,386 600,386 600,386 - South-east Chakaria 8,512 4,758 411 8,54 Maiskhali Island 1,645 n/a 2,773 290 Matabar Island 125 n/a 315 104 Jaliardwip Island 140 146 13 133 Naf River 667 n/a - 667 Total: 613,470 n/a 605,897 9,734 Loss  of  mangrove  areas  in  Bangladesh  aLributed  to  shrimp   culture  (Shahid  and  Islam,  2002)   •  There are reports that shrimp farming is not solely responsible for increased soil salinity. •  Reduction in upstream freshwater flows, together with changes in siltation patterns and extensive groundwater extraction has had a much more profound effect on the salinity increase in coastal region (Huntington, 2003).
  25. 25. Environmental impact of shrimp farming •  Degraded soil qualities due to 5-15 years of continuous shrimp farming in the areas were minimized with the beginning of present rice– shrimp rotation practices (Ali, 2006) •  Shrimp pond effluents impact on surrounding water quality is not yet a primary issue of concern (Bergheim et al., 2002). •  Biodiversity loss has been minimized through adequate supply of hatchery bred shrimp PL •  Water quality problem – mainly due to shallow (<60 cm) water depth.
  26. 26. Social impact of shrimp farming •  Literature available on social issues highlighting negative social consequences : land and water use conflict, income inequality, displacement of small and marginal farmers, etc. (Ahmad,1996; Alauddin and Tisdell, 1998; Begum and Alam, 2000) •  Positive social benefits are also recognized : mobility and diversification of the sources of income, increased employment, greater household food security, education and health facilities, communication, etc (Begum and Alam, 2000; Pokrant and Bhuiyan, 2001) •  With the gradual but widespread increase in owner occupation, reduction in gher size and operation, paddy farmer vs shrimp farmers conflict has much been reduced Huttington, 2003).
  27. 27. Social impact of shrimp farming •  With the gradual but widespread increase in owner occupation, reduction in gher size and operation, paddy farmer vs shrimp farmers conflict has much been reduced Huttington, 2003). Negative consequences (Ahmad, 1996; Alauddin and Tisdell, 1998; Begum and Alam, 2000)   Positive consequences (Begum and Alam, 2000; Pokrant and Bhuiyan, 2001)   Land and water use conflict Income inequality Displacement of small and marginal farmers Violence, etc.   Mobility and diversification of the sources of income Increased employment Greater household food security Education and health facilities Communication, etc  
  28. 28. Sectorial linkage and livelihoods (Alauddin  and  Hamid,  1998).   More than 600,000 people iengaged in activities related to shrimp aquaculture (Alam and Phillips , 2004) ; 25% are women
  29. 29. Conclusion •  The future development challenge in brackishwater aquaculture should focus on : •  Multidisciplinary empirical R&D to explore the development prospects of regulated shrimp cultivation protecting environment and agriculture. •  Assessment of the carrying capacity of different areas of coastal zones for the production and shrimp and rice. •  Identification area/zone specific farming pattern.
  30. 30. Conclusion •  Improvement of land-water management system are of prime importance to setting R&D strategies. •  Supply and value chain at each level of production and marketing for greater benefit of producers and consumers as well. •  Policy guidelines with flexibility to respond effectively to changes in different variables that determine success and failure of shrimp farming.

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