Growth and Survival of Blue Swimming Crab (Portunus pelagicus L.)In Different Rearing Substrates and Stocking Densities
The study of the growth and survival of blue swimming crabs is important to optimize its production and explore the development of net-cage crab culture as the culture scheme for production of blue swimming crabs. This paper investigates the growth and survival rate of Portunus pelagicus at 15 and 30 days of culture using two rearing substrates (net and sand) and three stocking densities (15, 30 and 45 crabs/m2). Physicochemical parameters such as the dissolved oxygen, salinity, water temperature, and water transparency were also gathered across the days of culture to explain other factors that may influence survival rate of crabs during culture. Results showed no significant differences for both growth rate in terms of carapace width and body weight and survival rate. Significant interaction between the stocking rate and rearing substrates on the growth rate in terms of carapace width during the 15 days of culture were observed. Poor growth and survival rates of the crabs may have been the result of cannibalism and poor quality of bottom substrates like silt and abrupt change of water quality namely salinity and transparency. It is recommended to validate the results in a more favorable rearing environment. Management strategies to control predation may be tested and implemented when culturing blue swimming crabs in cages and pens.