Blue crabs, Callinectes sapidus, stocked in cages at two different densities both with and without artificial habitats were compared for growth and survival in a power plant discharge canal and in a pond. Survival was higher for crabs in the pond but growth was significantly greater for those in the discharge canal. Artificial habitats increased survival of crabs cultured in the discharge canal but had no effect on those caged in the pond. In the laboratory no significant differences were found in weight, carapace width, or survival of crabs selected at random in regards to molting cycle and placed in individual molting chambers at 30 C and ambient temperatures (21-29 C). In 35 days the greatest increases in carapace width for individual crabs were 52, 33 and 14% for small, juvenile and sub-adult crabs, respectively. Crabs, all sizes pooled, molted earlier at 30 C than at ambient temperatures (22.2 vs 25.0 days to first molt). A raft holding wire cages with individual molting chambers is proposed for the commercial production of soft shell crabs in heated effiuents.