February 15-18, 2009 Washington State Convention Center Seattle ...

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CULTURE OF ALLIGATOR GAR Atractosteus spatula IN RECIRCULATING SYSTEMS
Timothy A. Clay*, Mark D. Suchy, Allyse M. Ferrara, Quenton C. Fontenot and Wendell J. Lorio
Bayousphere Research Laboratory
Nicholls State University
Thibodaux, LA 70310 USA
tclay1@gmail.com
Juvenile alligator gar Atractosteus spatula were exposed for 21 days to four trials: (1) fluctuating ambient temperatures
(28.7±1.5 C) and fed 4% body weight split equally among three daily feedings; (2) controlled average temperature(27.5±0.5
C) and fed 4% body weight split equally among three daily feedings; (3) fluctuating temperatures(28.4±2.6 C) and fed 4% body
weight split between two daily feedings; (4) feed amounts of 8, 4, 2, or 1% body weight per day split equally among three daily
feedings. All gar were fed 2.4mm Aquamax extruded floating pellets (45% protein/16% lipid). Fish were stocked at 0.5 fish/l
in 95 liter circular tanks with 60 liters of water at 4 ppt in either individual or four tank recirculating systems. Total biomass
was not different (α=0.05) between the ambient and fluctuating temperatures or between different feeding frequencies. Fish
fed 8% body weight (36.8 g) were larger than fish fed lower amounts. Survival was not different among any treatments, though
there was a general increase in survival in higher feed tanks. Condition was not significantly different among temperature and
feeding frequency trials. Gar fed 4% feed had the highest condition (0.40) and lowest feed conversion rates (2.15). Increasing
feed amounts resulted in significantly increased total-ammonia-N and decreased DO levels, with gar fed 8% feed experiencing
total ammonia-N (9.31±8.9 mg/l) and DO (3.1±1.6 mg/l). The results of this study suggest juvenile alligator gar should be fed
three times a day at 4% body weight.