Growth in juvenile Callinectes sapidus

Cohorts of juvenile (5-20mm) Callinectes sapidus were collected from the same site in North Carolina in fall and spring of 2000 and 2001. Crabs were held in captivity for 120-day experiments to determine the effects of different salinity (5,15,24,30 0/00) and temperature (20,23,24,25,27,30 degrees centigrade) on their growth and molting. All crabs had remarkably consistent growth rates despite the wide environmental differences. The duration of their molt cycles was also very consistent, between 15-28 days on average. In some groups, the number of molts completed during the 120-day study varied with salinity and temperature. A cohort of crabs collected in fall 2001 had exceptional mean molt increments; they increased in size at each molt more than any other replicates. Eyestalk ablation induced crabs to grow larger at each molt, but they did not molt faster than controls. Juvenile Callinectes sapidus adapt well to wide variations in salinity and temperature, with little decrement on their growth or molting. Some cohorts of the crabs grew faster than others; this may be due to their initial condition when they recruited to the estuary. Supported by NSF: DBI 99-78613