Post on 05-Feb-2018
SHRIMP FARMING IN
SALINE GROUNDWATER IN
ARIZONA, USA
Kevin Fitzsimmons
University of Arizona
Tucson, Arizona
ABSTRACT
� Environmental restrictions on shrimp
aquaculture.
� Inland culture avoids problems.
� Low salinities will support growout.
� Problem areas with aquaculture.
� Reuse of effluent for field crops.
� Sustainable and profitable?
INTRODUCTION Environmental Constraints
� Loss of mangroves and other coastal
vegetation.
� Effluents and nutrient enrichment
� Impacts (real and imagined) on wild
shrimp and other species (diseases,
exotic species, genetic contamination).
� Changes in estuarine flow patterns.
INTRODUCTION Low salinity inland culture
� Florida, Harbor Branch Oceanographic
� Mexico, Colima; Aquagranjas
� Thailand, multiple
� India, Andhra Pradesh
� Texas, Texas A&M
� Arizona, Gila Bend and Aztec
INTRODUCTION Source water
� Low (1-2 ppt or 1000 -2000 ppm TDS).
� Med (3-5 ppt or 3000 - 5000 ppm TDS)
� Low can be used on conventional crops.
� Medium salinity effluent constitutes a
disposal problem.
� Medium salinity effluent can be used for
algae culture or halophyte crops.
INTRODUCTION Reuse of low salinity (1-2 ppt) effluent
water
� Has been used for olive trees, sorgum,
and cotton.
� Could be used for sugar beets,
asparagus and dates.
INTRODUCTION Reuse of medium salinity (3-5 ppt) effluent
water
� Halophyte agriculture.
� Seaweed culture.
� Bivalve culture.
INTRODUCTION Halophytes
� Many families of plants have halophytic
representatives.
� Grasses, bushes, trees
� Many are from arid regions
� Native species are usually available
� Can be used for forage, biomass,
landscaping, and dust control
RESULTS Gila Bend, Low salinity
� Stocking Litopenaeus vannamei
– 35 shrimp/m2 @ 0.4 g
� Feed - Rangen
� Water exchange: 10-15%
� Aeration
– Paddlewheels
– Diffusers
RESULTS Gila Bend, Low salinity
� Survival 47%
� Harvest after 85 days, @ 19 g
� Yield
– 4,000 kg/ha
– 10 ha of ponds
RESULTS Gila Bend, Low salinity
� Algae bloom
– more characteristic of freshwater
– nutritional value for shrimp needs to be
studied
� Problems
– Hemocytic enteritis
– Gill fouling
RESULTS Gila Bend
Typical algae counts in August 1998
� Cyanophyta (Blue-Green algae)
– Gomphosphaeria (104 cells/ml)
– Lyngbya (104 cells/ml)
– Microcystis (104 - 106 cells/ml)
– Merismopedia (104 - 105 cells/ml)
RESULTS Gila Bend
Typical algae counts in August 1998
� Chlorophyta (Green algae)
– Chlorella (104 - 105 cells/ml)
– Coelastrum (104 cells/ml)
– Pediastrum (103 cells/ml)
– Scenedesmus (104 cells/ml)
RESULTS Gila Bend
Typical algae counts in August 1998
� Diatoma (Diatoms)
– Gomphonema (104 cells/ml)
– Navicula (103 cells/ml)
– Nitzchia (103 -104 cells/ml)
– Synedra (102 cells/ml)
RESULTS Aztec, Medium salinity
� Stocking L. vannamei, L.. stylirostris
– 5 to 10 shrimp/m2 @ PL 20
� Feed - Rangen
� Water exchange: limited
� Aeration:none
RESULTS Aztec, Medium salinity
� Survival L. vannamei, L. stylirostris
– 0 to 30%
� 3 grams per week at one point
� Harvest after 120 days, @ 10 -20 g
� Yield
– 0 to 1,000 kg/ha
– 40 ha of ponds
Conclusions
� Shrimp can be produced in low salinity
groundwater.
� Commercial quantities can be
produced.
� Low salinity effluent waters can be used
for conventional field crops.
� Medium salinity effluent can be used for
halophyte crops.
Conclusions
� Sustainability will not be demonstrated
until salt levels in soils are tested after
several years of irrigation.
� Need to determine manipulation of
algae species.
Conclusions
� Markets are prepared to pay a premium
for fresh, locally grown shrimp.
� Profitability will be determined if more
crop cycles can be completed without
significant losses due to disease or
other environmental conditions.
Additional information
� Websites
– http://ag.arizona.edu/azaqua
– http://www.desertsweetshrimp.com
– http://www.shrimp.ga.com
– http://www.sciam.com/1998/0898issue