International cooperation in
evaluation of environmental &
economic impacts of tilapiashrimp polycultures
Remedios Bolivar, Yang Yi
Wilfrido Contreras, Kevin Fitzsimmons
Aquaculture CRSP
US Aquaculture Meetings
Feb. 20, 2003
Introduction
More
efficient use of resources (water,
land, feed, labor, etc)
Shrimp and tilapia are two of the most
important aquaculture products
They share many ecological
characteristics, polyculture worldwide
Farm experience suggest benefits to
polyculture
Opportunity to restore abandoned farms
Introduction
Conducted
survey in Thailand,
Vietnam, Mexico, the Philippines and
the US.
Followed with field trials in Thailand
and Mexico
Preliminary lab studies support field
reports
Survival and growth rates improved
Reported benefits
Reduction
in levels of pathogens
(green Vibrios and viral infections)
Fish reduce accumulation of
wastes in production units
Fish encourage beneficial algal
blooms
Tilapia consume potential disease
vectors, especially crustacea
Reported benefits
Bring
disease ravaged farms back into
production
Lower density, less technology
intensive
Fish can be sold into local markets to
improve domestic food supply
Displaced social groups may be able
to take advantage of abandoned farms
Several models
Tilapia
in cages in shrimp pond
Tilapia in supply reservoirs
Tilapia and shrimp loose in pond
Tilapia and shrimp in crop rotation
Tilapia 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 infrastructure
Exporting tilapia to US and EU
Tilapia production in Ecuador
and shrimp viral infections
TILAPIA PRODUCTION IN ECUADOR
30,000
Production (m t)
25,000
20,000
15,000
10,000
White Spot
5,000
Taura
IHHN
0
1990
1991
1992
1993
1994
1995
1996
Year
1997
1998
1999
2000
2001
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 results
Average
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}
Conclusions
Polyculture
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.
Conclusions
Tilapia
in supply reservoirs
most common
Cage culture of tilapia in
shrimp pond
Crop rotation of tilapia after
shrimp disease outbreaks
Thank you for your interest
Research
support provided by the
Pond Dynamics/Aquaculture
CRSP
Questions ????