Length-weight relations and growth patterns of the rock pool prawn (Palaemon elegans) in the coast of Gilan province

In the southern basin of Caspian Sea, rock pool prawn (Palaemon elegans) is very abundant and plays an important role in the food chain of this region. The aims of this study were to investigate the biometry characteristics, determine the long-weight relations and growth pattern of this species in the coasts of Gilan province. At each sampling stage, environmental factors were measured and the samples were transferred to the laboratory after stabilization and biometry according to the standards. The data were classified based on gender and three stages before, time and after spawning. The results showed that females had more weight than males and the average total weight of females before, at and after spawning were 0.759, 1.246, 0.518 g and the average weight of males was 663, respectively. 0.00, 0.900 and 0.337 g and there was a significant difference in time between the two sexes (P<0.05). Significant differences in total length, carapace length, propude length and total weight were also observed in the specified time intervals (P<0.05). Examination of longitudinal-weight relations showed that the value of b in male and female shrimp was close to 3 and had an allometric positive, although this relationship was always higher in males than females and at the time of spawning with a significant reduction in females. It was observed due to physiological changes (P<0.05).