Productivity and Profitability of Mithraculus forceps Aquaculture

Red-clinging crabs Mithraculus forceps are used for their ability to control nuisance algae in marine aquariums. Their larval and juvenile culture protocol has already been successfully developed. The objective of this work is to build a model that integrates the effect of different abiotic and biotic factors (temperature, stocking density, prey density), as well as space (number and volume of tanks) in production and economic parameters (costs of feed, labour and maintenance, market price and profit). The model aimed to be used as a tool to support management decisions. Overall, the model was able to integrate previously collected data and produce expected forecasts of M. forceps larval and juvenile culture reared under different combinations of temperature, stocking density, and prey density. Sensitivity analysis revealed that temperature was the most important factor regulating survival and growth, and consequently profit. According to the model, a batch of 1500 larvae reared in ten 10 L tanks in optimal conditions (10 prey mL ^{− 1} and 28 °C) and then, as juveniles, in a 3 m ² water table at 28 °C, is expected to reach commercial size in 225 days.