The Influence of Salinity on the Growth of Juvenile Shortnose Sturgeon

Abstract

The shortnose sturgeon Acipenser brevirostrum is a promising aquaculture candidate, but optimal culture conditions remain to be defined. Given that salinity is known to affect the growth performance of fish, we examined the effect of salinity on the growth of juvenile shortnose sturgeon in aquaculture. Because the behavior and consequently the salinity exposure of juveniles in the wild is largely unknown, the optimal culture salinity for growth of juvenile shortnose sturgeon is difficult to predict. Juveniles (age, 16 months; mean weight, 273 g) were reared at four salinities (0, 5, 10, and 20‰) for 10 weeks at 18°C. Fish were fed a commercial salmon feed (49% crude protein, 20% crude fat, 4% crude fiber) continuously at a rate of 0.75% of their body weight per day. Weight gain and feed conversion rate (FCR) were significantly (P < 0.01) affected by salinity. Fish reared at 0‰ showed significantly more weight gain and greater FCR than the fish raised at all other salinities. Fish reared at 20‰ exhibited the poorest growth. Thus, we conclude that salinity may compromise the growth of juvenile shortnose sturgeon and suggest that, in commercial operations, salinity should be 0‰.