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International cooperation in evaluation of environmental & economic impacts of tilapia-
shrimp polycultures
Remedios Bolivar, Yang YiWilfrido Contreras, Kevin Fitzsimmons
Aquaculture CRSP
US Aquaculture Meetings
Feb. 20, 2003
IntroductionMore efficient use of resources (water, land,
feed, labor, etc)Shrimp and tilapia are two of the most
important aquaculture productsThey share many ecological characteristics,
polyculture worldwideFarm experience suggest benefits to polycultureOpportunity to restore abandoned farms
IntroductionConducted survey in Thailand, Vietnam,
Mexico, the Philippines and the US.Followed with field trials in Thailand
and MexicoPreliminary lab studies support field
reportsSurvival and growth rates improved
Reported benefitsReduction in levels of pathogens (green
Vibrios and viral infections)Fish reduce accumulation of wastes in
production unitsFish encourage beneficial algal bloomsTilapia consume potential disease
vectors, especially crustacea
Reported benefitsBring disease ravaged farms back into
productionLower density, less technology intensiveFish can be sold into local markets to
improve domestic food supplyDisplaced social groups may be able to take
advantage of abandoned farms
Several modelsTilapia in cages in shrimp pondTilapia in supply reservoirsTilapia and shrimp loose in pondTilapia and shrimp in crop rotationTilapia to treat/re-use shrimp
effluent
Tilapia - shrimp polyculture
Philippines - Early adoption of polyculture
Severe disease outbreaks in shrimp industry in 1990’s
Major producer of tilapia Developed tilapia-shrimp polyculture
system on Negros Island Crop-rotation, tilapia in cages, and tilapia
in reservoir Have been operating for 6 years
Tilapia-shrimp farm in Sonora, Mexico
Tilapia - shrimp polyculture in Mexico
Tilapia-shrimp polyculture in full seawater Effluent from shrimp goes to tilapia Tilapia consume uneaten feed, fecal
strands, macro-algae and reduce organic matter levels in effluent
Additional experimental trials being conducted at Autonomous University of Tabasco, survey in Sinaloa
Tilapia-shrimp production in Ecuador and Peru
Supplementing shrimp because of white spot and other shrimp diseases
Crop rotation, tilapia in supply reservoirs
Using shrimp infrastructureExporting tilapia to US and EU
Tilapia production in Ecuador and shrimp viral infections
TILAPIA PRODUCTION IN ECUADOR
0
5,000
10,000
15,000
20,000
25,000
30,000
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001
Year
Pro
du
ctio
n (
mt)
IHHN TauraWhite Spot
Red strains of tilapia most popular for brackish polyculture systems
Tilapia production in outside ponds with shrimp in covered
ponds
Thailand farm-based polyculture systems
Tilapia in cages in shrimp ponds Tilapia in sequential polyculture before and
after shrimp ponds Farmers testing impacts on microflora
Thailand experimental polyculture systems at AIT
Shrimp survival - 90% Shrimp yield - 3,000 kg/ha Tilapia survival - > 90% Tilapia yield - 1,500 kg/ha Tilapia growth - 10g to 300g in 10 weeks Shrimp survival and yield was lower in
monoculture control
US Shrimp-Tilapia polyculutre
Tilapia production in supply reservoirs
Condition water before shrimp
Tilapia in supply reservoir
Arizona resultsAverage tilapia yield - 2,400 kg
in 0.04 ha ponds (eight months) {60,000 kg/ha}
Average shrimp yield - 2,000 kg in 0.1 ha ponds (five months) {20,000 kg/ha}
ConclusionsPolyculture with shrimp will become
common in most shrimp farming areas
Already practiced in Thailand, Philippines, Vietnam, Mexico, US
(Arizona and Florida), Ecuador, Peru, Eritrea. Will expand.
ConclusionsTilapia in supply reservoirs most
commonCage culture of tilapia in shrimp
pondCrop rotation of tilapia after
shrimp disease outbreaks
Thank you for your interestResearch support provided by the
Pond Dynamics/Aquaculture CRSP
Questions ????