Bar Grading of Pellet-Reared Alligator Gar in Tanks and Raceways

Our objective was to determine the influence of bar grading on production of Alligator Gar in tanks and raceways.  In study 1, 21-dph Alligator Gar were stocked in 75-L acrylic tanks at a density of 3.2 fish/L.  Alligator gar were offered formulated feed at 10% of body weight/d for 35 d.  Fish were graded twice each week.  In study 2, 19-g fish were stocked in concrete raceways at a density of 0.03 fish/L.  Fish were offered Golden Shiner at a rate of 10% of body weight/d and formulated feed ad libitum up to 10% of body weight/d for 36 d.  Fish in raceways were also graded twice each week.  Alligator Gar from tanks averaged (SD) 119 (24) mm TL and weighed 9 (7) g. Growth was significantly higher, but survival and yield were significantly lower in the control groups than in the graded treatments.  Alligator Gar from raceways averaged 236 (26) mm TL and weighed 66 (24) g.  Growth in length was significantly greater in the control groups than in the graded treatment.  However, yield, survival, and growth in weight were not significantly different between the control group and the graded treatment.