Stock assessment of the mud crab ( collected from the terrestrial edge of the Sundarbans mangrove forest, Bangladesh.

We estimated mud crab () population parameters to determine recruitment patterns, asymptotic carapace width ( ), growth coefficient (), mortality rate (, , and ), exploitation rate () and relationship between body weight and carapace width ( - ) in the terrestrial edge of the Sundarbans mangrove forest, Bangladesh. Baited long lines and traps were used to collect crab samples from the terrestrial edge of the mangroves (up to 10 km inside of the Sundarbans mangroves) monthly for a year (Jan 2021-Dec 2021). These frequency data were utilized to determine population characteristics. Based on the  ×  relationship, male crabs increased their faster ( = 2.89,  = 0.86) than females ( = 2.29,  = 0.82). Crabs displayed negative growth allometry, significantly differed from the isometric growth ( = 3). Both male and female was estimated to be 126.00 mm and 113.40 mm, with values of 0.50 yr and 0.48 yr, respectively. The total mortality (), natural mortality (), and fishing mortality () of male and female crabs were 1.89 yr and 1.84 yr, 0.79 yr and 0.80 yr and 1.10 yr and 1.04 yr respectively. Both sexes were recruited using a bimodal recruitment strategy, with a significant peak from March to June. However, young crabs were present year-round. The virtual population analysis (VPA) shows that males and females are caught at smaller sizes (60-90 mm). The estimated exploitation rate () exceeds (0.58 for males and 0.57 for females) the optimum exploitation level ( = 0.50) and values were close to the projected maximum yield per exploitation rate  = 0.655 for males and 0.647 for females) which indicated over-exploitation of the mud crabs from the territorial edge of the Sundarbans mangrove forest of Bangladesh and hence suggested for proper management.