Shortnose sturgeon, Acipenser brevirostrum, range from Canada to Florida and are listed as an endangered species in the United States. During 1985, a cooperative state/federal program focused on development of nursery systems for production of stockable size juveniles. Mortality was high (80%) during the first 2-3 months of tank rearing trials in spite of the use of various disease control agents and differing culture techniques. However, once a size of -180 mm T.L. (30 g) was attained, mortality essentially ceased. Indoor intensive tank systems were more suitable than ponds for producing small juveniles. Growth and survival of advanced juveniles in indoor tanks was similar among initial population densities ranging from 5.4 to 118.4 fish/m2 tank bottom area. A standing crop of 17.2 kg/m' was attained at the highest population density and overall feed conversion for all advanced juveniles was 1.4 using a soft-moist trout ration. Mean size of the 264-day-old fish was 332.8 T.L. 148.2 g. During the course of the study, 918 advanced juveniles were produced and 596 were released as part of a stock rehabilitation effort.
