Growth and survival of first-feeding and fingerling Atlantic sturgeon under culture conditions

We performed rearing studies with first-feeding fry and fingerling Atlantic sturgeon Acipenser oxyrinchus oxyrinchus produced from streamside spawning of wild Hudson River adults. In all, 20,000 larvae were reared in 54-L cir cular tanks at initial densities of 3.7-29.6 fish/L (0.06-0.52 g/L). At the onset of exogenous feeding, diet treatments included live brine shrimp Art emia sp., frozen brine shrimp, or commercially formulated Biokyowa B-250. A t the end of the 26-d study, all treatments but two had survival greater th an 93%. Mean specific growth rate (SGR) was inversely proportional to fish density. Fish fed frozen brine shrimp were smaller but had equivalent survi val to those fed live brine shrimp. Atlantic sturgeon converted to formulat ed feed with less than 25% mortality at mean total length and weight of 34. 5 mm and 0.18 g in 20-26 d at initial stocking densities of 7.4 fish/L or l ess. A subsequent study was performed with fingerlings at densities of 0.37 -2.22 g/L. These fingerlings were offered Zeigler sturgeon diet at 3% body weight daily. After 28 d, mortality ranged from 4.7% to 13.0%. Atlantic stu rgeon from all treatments were similar in weight and total length. Our stud y showed that first-feeding Atlantic sturgeon under conditions of artificia l rearing require low initial stocking densities and 20-26 d of a continuou s supply of live brine shrimp to achieve a minimum size necessary for succe ssful conversion to formulated feed. Fingerling Atlantic sturgeon that conv ert to formulated feed can be stocked at initial densities up to 2.22 g/L a nd reared for 28 d with resulting feed conversion ratios of 0.50 or better and at least 90% survival.