Study on sex ratio and weight-Carapace of Blue Swimming Crab (Portunus segnis Forskal, 1775) in Hormozgan province waters

This study was to record Some Biological Characteristic of blue swimming crab (Portunus segnis, Forskal 1775) in Hormozgan province waters (Ciric to Bandar Abbas). Total 722 Specimens were caught by shrimp trawl and fixed gill net during Jun 2011 to May 2012. The rate of male and female to the total catch composition was 57.9% and 42.1% respectively. Male to female sex ratio was obtained 1:1.3 that was differed significantly (P<0.05). Carapace width (CW) and weight (W) ranges were from 5.20 to 17.90 cm and 2.80 to 395.78 g respectively. The b (slope regression) value of the weight-Carapace width (CW) relationship ranges were 3.24 and 2.69 for male and female respectively. The b (slope regression) value of the weight-Carapace length (CL) relationship ranges were 3.02 and 2.76 for male and female respectively that showed allometric growth (p<0.o5). Also Mean±SE weight calculated 107.46±70.05 and 114.44±49.81 for male and female respectively that was different significantly (P<0.05). Condition factors (CF) was calculated 6.86±2.66 and 65.54±13.06 for Carapace width (CW) and Carapace length (CL) respectively. The present paper is useful for fisheries biologist in order to more recognize of stock characteristics of this species.