Callinectes danae Smith, 1869 and C. ornatus Ordway, 1863 constitute an important portion from the fishing products at Guanabara Bay. Both species compose a significant by-catch fraction being a lot discarded during shrimp trawlings along Brazilian coast. Growth curves were estimated by modal progression analysis. For the biological parameters it was applied the Bertalanffy growth function and for the age it was used its inverse formula. Growth curves of C. danae and C. ornatus were respectively: ♂ LC = 120 (1 - e -0,005t), ♀ LC = 113 (1 - e -0,005t); ♂ LC = 94 (1 - e -0,005t) and ♀ LC = 110 (1 - e -0,005t). The age for both species reached around 2.5 years, besides to confirm growth curves. Growth study in crustaceans is very important, because besides supplying biological information it subsidizes fishery management for exploted species.
Fishery; management; swimmingcrab; by-catch
