Bringing  back  seasonality  into  coastal  aqua3c  agricultural  systems:  

 shi$ing  from  shrimp  monoculture  to  more  produc3ve,  diversified  and  resilient  systems  

BANGLADESH  

Salinity fluctuates from high in dry season to medium in rainy season

Research site

Research Questions:

1.  Can  brackishwater  aquaculture  system  produc9vity  be  increased?  2.  What  species  combina9on  is  more  suitable  for  increased  produc9vity,  profitability  and  resilience  in  year-­‐round  brackishwater  areas?  3.  What  are  the  costs  and  benefits  of  monoculture  versus  polyculture?  

4  

Before  

Construc3on  

Ponds  Pond  

Aquaculture Treatments in 2012

3 treatments with 4 replications:

1. Farmer’s mgt: Polyculture, shrimp+ different fish sp

2. Improved mgt1: Rotational Monoculture, shrimp-tilapia-prawn (Cycle 1, 2 & 3)

3. Improved mgt 2: Rotational Polyculture, shrimp+tilapia – tilapia+tengra - prawn+tengra( Cycle 1, 2 & 3)

Tilapia  +  CaEish  

Prawn  (fresh  water)   Shrimp  (brackish  water)  

Aquaculture Treatments in 2013

3 treatments with 4 replications:

1. Farmers’ mgt : Polyculture Shrimp+ several fish spp, multiple stockings & harvests

2. Improved mgt 1: Rotational monoculture Dry season - shrimp (2 crops) (Cycle 1 & 2)

Wet season - tilapia (Cycle 3)

3. Improved mgt 2: Rotational polyculture Dry season - shrimp+tilapia (2 crops) (Cycle 1 & 2)

Wet season - polyculture rohu + singh + magur (Cycle 3)

Carp  

Singh  &  Magur  

Shrimp    

Nona  tengra  

Tilapia  

……………Dry  season……………………  ……………….Wet  season……………………………………………………………  

CaFish  (3  spp)  

Aquaculture treatments (4 reps)

Treatm

ents  

Cultu

re  

paLerns  

2012   2013  

Cycle  1   Cycle  2   Cycle  3   Cycle  1   Cycle  2   Cycle  3  

Farmer’s  prac3ce   Poly  

Shrimp  +  different  sp  of  fish  (mul3ple  stocking  &  

harves3ng)  

Shrimp  +  different  sp  of  fish  (mul3ple  stocking  &  

harves3ng)  

Improved  prac3ce  1   Mono   Shrimp   Tilapia  

   

Prawn      

Shrimp   Shrimp  

   

Tilapia      

Improved  prac3ce  2  

 Poly   Shrimp  

Tilapia  Tilapia  Tengra  

   

Prawn    Tengra  

   

Shrimp  Tilapia  

 Shrimp  Tilapia  

 

Rohu    Singh  Magur  

Managed  by  farmers  

Management

Prac3ce   Farmer’s  Prac3ce  

Improved  1  &  2  

Liming   200  kg  ha-­‐1   200  kg  ha-­‐1  

Water  filtering   Unfiltered   Filtered  Predatory  Fish   No  control   Controlled  Disinfec3on   No  disinfec9on   Disinfected  Fer3liza3on   No  fer9lizer   Fer9lizer  &  dolomite  Shrimp  seed   Not  PCR  tested   PCR  tested  Feed   No  feed   Feeding    Water  replenishment   When  needed   When  needed  Post  stocking  fer3liza3on   Very  insufficient   When  primary  

produc9on  is  low  Fish  seed   Some  wild   All  from  hatcheries  

Timeline 2012

Shrimp & fish Stocking 1 Shrimp

disease in some ponds

Harvest 3

April March Aug. Dec.

Harvest 2

Sept.

Stocking 3 Harvest 1 & Stocking 2

June July Nov. May Oct.

Dry season Wet season

Timeline 2013

Shrimp & fish Stocking 1

Rice harvest

April March Aug. Dec.

Harvest 2

Harvest 3

Sept.

Harvest 1 Stocking 2

May July Nov.

Stocking 3

Dry season Wet season

Water  Depth  (2012  versus  2013)  

2012  

2013  

30  40  50  60  70  80  90  

100  110  

1   15  

28  

42  

56  

70  

84  

98  

112  

126  

140  

154  

168  

182  

196  

210  

224  

238  

252  

266  

280  

Depth  (cm)  

7  March  

Farmer's  prac3ce  Monoculture  Polyculture  

20  30  40  50  60  70  80  90  100  

1   14  

28  

42  

56  

70  

84  

98  

112  

126  

140  

154  

168  

182  

196  

210  

224  

238  

252  

Depth    (cm)  

Days  of  culture  14  M

arch  

Farmer's  prac3ce  Monoculture  Polyculture  

Cycle  1  

Cycle  2  

Cycle  3  

Cycle  1  

Cycle  2  

Cycle  3  

Water  Salinity  (2012  versus  2013)  

2012  

2013  

Cycle  1  

Cycle  2  Cycle  3  

0  

5  

10  

15  

20  

25  

1   15  

28  

42  

56  

70  

84  

98  

112  

126  

140  

154  

168  

182  

196  

210  

224  

238  

252  

266  

280  

Salin

ity  (p

pt)  

7  March  

Farmer's  prac3ce  

Monoculture  

Polyculture  

0  

5  

10  

15  

20  

25  

1   14  

28  

42  

56  

70  

84  

98  

112  

126  

140  

154  

168  

182  

196  

210  

224  

238  

252  

Salin

ity  (p

pt)  

Days  of  Culture  14  M

arch  

Farmer's  prac3ce  Monoculture  Polyculture  

Cycle  1  Cycle  2  

Cycle  3  

Results

0  

500  

1000  

1500  

2000  

2500  

3000  

3500  

4000  

4500  

Farmer's  prac3ce   Monoculture   Polyculture  

Yield  (kg  ha

-­‐1)   Shrimp  

Fish  

2012  

a  

b   c  a  

b  

c  

0  

500  

1000  

1500  

2000  

2500  

3000  

3500  

4000  

Farmer's  prac3ce   Monoculture   Polyculture  

Yield  (kg  ha

-­‐1)   Shrimp  

Fish  

2013  

a  

b  c  a  

b   c  

(1)  System  produc3vity    -­‐  annual  Produc3on  (kg/ha)  in  2012  &  2013    

2012

Culture patterns

Cycle-1 (91 days)

Cycle-2 (71days)

Cycle-3 (100 days) Total

Shrimp Tilapia Tilapia Tengra Prawn Tengra Shrimp Fish

Farmer’s practice

278 days *209.84a 728.14a

Mono 197.77 -­‐   2367.48 -­‐  

 363.63  

-­‐   556.40b 2367.48b

Poly 172.64 1163.41   1519.78      

352.34    

231.74 286.50   404.38c 3322.04c

2013

Culture patterns

Cycle-1 (70 days)

Cycle-2 (50 days)

Cycle-3 (99 days) Total

Shrimp Tilapia Shrimp Tilapia Magur+ singh

Tilapia/ rohu Shrimp Fish

Farmer’s practice

259 days 390.05a 659.41a

Mono 565.62 -­‐   291.77   - - *3307.71 857.39b 3307.71b

Poly 373.64 1744.45   193.19   777.90   557.63   **480.05 566.83c 3560.02c

Cycle-­‐wise  produc3on  (kg/ha)  in  2012  &  2013    

Fish  Category   2012**   2013**   Remarks  

Tengra-­‐Tilapia   41654.38a  -­‐  Risk  free;  Less  profit  -­‐  Tengra  may  escape  if  dikes  are  not  good  

Tengra  -­‐Prawn   116000b  

-­‐  Depends  on  availability  of  prawn  Juvenile;    -­‐  Tengra  may  escape  if  the  dikes  are  not  good  

Carp-­‐Singh-­‐Magur   147816.11c  

-­‐  Singh  &  Magur  culture  depends  on  rainfall  -­‐  Singh  &  Magur  may  escape  if  the  dikes  are  not  good  

Shrimp-­‐Tilapia   101450.71b   128000b  -­‐Shrimp  risky  but  9lapia  provides  the  back  up  

(2)  Species  combina3ons  -­‐  gross  margin  (BDT/per  cycle/ha)  from  different  polyculture  species  composi3on    

(3)  Polyculture  vs  monoculture  

-­‐100  

0  

100  

200  

300  

400  

500  

600  

700  

Farmer's  prac3ce   Monoculture   Polyculture  

BDT  1000  ha-­‐

1    

Variable  cost  Total  return  Gross  margin  

2012  

a  

b  

c  

-­‐100  

0  

100  

200  

300  

400  

500  

600  

700  

800  

Farmer's  prac3ce   Monoculture   Polyculture  

BDT1000  ha

-­‐1    

Variable  cost  Total  return  Gross  margin  

2013  

a  

b   b  

Cost,  return,  gross  margin    

(including  farmer’s  labor  &  land  leasing  value)  

Ponds Species Total  cost  (BDT/ha)

Produc3on  (kg/ha)

Sale  (BDT/ha)

Gross  return  (BDT/ha)

3 Shrimp

212240  515.97   257985   297985  

Tilapia 2557.58   281333.8   281356  

8 Shrimp  

182147    

349.26   174630   174630  

Tilapia 2079.62   228758.2   228758  

6 Shrimp

157900  0   0   0  

Tilapia 1930.79   193079   193079  

11 Shrimp

157137  0   0   0  

Tilapia 1920.71   192071   192078  

Impact  of  crop  diversifica3on  in  shrimp  ghers  (Shrimp  –  3/m2  &  3lapia  2/m2,    culture  period  –  91  DOC)

Promising  opportuni3es  for  scaling  !   275,000  ha  of  all  year-­‐round  saline  aquaculture  area  !  G2  extension  farmers  involved  par9cipatory  adop9on  trial  and  sharing  with  other  farmers  

!   Implemen9ng  community  water  management  for  brackishwater  aquaculture  with  BRAC  

!   Extension  materials  prepared  and  disseminated  

Key  implementa3on  challenges  Markets  systems  •  Access  to  quality  shrimp  and  fish  seed  •  Access  to  quality  feed  in  local  market    

Aquaculture  management  •  Maintaining  water  depth  •  Preven3on  of  escaping  cat  fish  through  dikes  •  Aqua3c  weed  control    

Community  •  Poor  feeder  canal  for  gravita3onal  water  exchange  (need  community  level  management  –  common  theme!)  

•  Poaching  risk  

Conclusion  

q  Significant  improvements  in  produc3vity  and  income  through  a  diversified  culture  system  under  beLer  management  prac3ces.  

q  Shrimp-­‐3lapia  polyculture  system  profitable  with  greater  resilience  compared  to  other  species  combina3ons.  Risks  of  shrimp  can  be  recovered  by  return  from  Nile  3lapia  

 

q  Polyculture  and  alternate  cropping  monoculture  more  profitable  than  current  prac3ces.  Gross  margin  from  polyculture  higher  than  monoculture  

 

Lesson  learned  q  Considerable   opportuni3es   exist   for   improving  

aquaculture  in  the  coastal  “year-­‐round”  saline  zone.  

q  Technologies  appear  to  be  very  “adoptable”  by  farmers  

q  Community   water   management   can   further   improve  op3ons  for  aquaculture  and  risk  management  

q  Possible  to  integrate  vegetable  produc3on  from  dikes  in  wet  season  and  support  livestock  food  by  growing  saline  tolerant  grass  on  the  dikes  

q  Saline  water  represents  an  asset….  

Aquaculture production must more than double by 2050 to satisfy projected fish demand Million tons

Sources:  Produc9on  data  1961–2010:  FAO  (2014a),  FAO  (2014b).  Aquaculture  produc9on  projec9ons  2011–2050:  Authors’  calcula9ons  assuming  a  linear  growth  rate  of  2  Mt  per  year.  

Project aquaculture production …. South Asia is a hotspot for future fish demand

•  S.  Asia  –    from  2.2  to  4.4  mt  •  India  –  from  3.9  to  8.6  mt