This work was performed by monthly sampling from June 2000 to May 2001 for population structure studies and by seasonal sampling from January to October 2002 for space and seasonal distribution studies, dividing the mangrove in three different areas. On the space-seasonal distribution study, 694 crabs were caught, where 45% was captured in area 1,36% in area 2 and 19% in area 3. There were significant differences between the number of individuals between area 2 and 3. For the population structure study a total of 742 crabs were captured, being 59% male, 32.7% female and 8.3% ovigerous females. The sex ratio was 1:0.69 (male:female), and the carapace width ranged from 9.6 to 25.0 mm CW in males and from 5.5 to 24.9 mm CW in females. The size class distribution was unimodal and the males were more frequent between 19.1 to 21.0 mm CW, while females between 17.1 to 19 mm CW. The sex ratio along each size class showed the male predominance in almost all classes except between the classes of 5.1 to 7.0 and 7.1 to 9.0 mm CW.
Populational biology; Sepetiba Bay; sex-ratio; tree crab
