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