Assessment of Soft-Shell Mud Crab (Scylla olivacea) Farming Trend in the Southwest Coastal Region of Bangladesh

Soft-shell crab aquaculture practices emerged as a profitable livelihood option in the study area due to its lower vulnerability to changing climatic conditions and high demand in the international market. Therefore, this study aims to identify the current growth of soft-shell mud crab farming to develop strategies to cope with future challenges. Random sampling was applied to collect primary empirical data from different stakeholders of the crab sub-sector based on structured and semi-structured questionnaires. In addition, focus group discussions (FGDs) and key informant interviews (KII) were arranged to collect information from a wide range of expert people to cross-validate the obtained information during the interviews. The study results indicated that the southwest region of Bangladesh has more than 380 farms having 5.55 ± 0.42 million seed crabs in demand in each cycle which is entirely dependent on wild stock. However, the wild crab harvesting amount has declined from 10.35 ± 2.07 to 4.38 ± 0.83 kg/day/person which represented a highly positive relationship with the active percentage of plastic cages that reduced from 99.43 ± 2.12% to 67.04 ± 4.75% during the investigated years. Farm mortality of stocking crabs has also increased by more than 8% in the last 9 years due to a lack of quality seed crabs. The soft-shell crab farmers preferred small stocking sizes to get quick moulting, ranging from 30.35 ± 2.59 to 43.50 ± 3.59 g. Most of the crab farmers used only tilapia fish as feed items leading to the increase in unit price from BDT 30.30 ± 1.98 to BDT 80.00 ± 2.46. The feeding demand and cost also increased many folds over the years with an increase in farm numbers and feed prices. So, crab hatchery development and formulated feed supply are inevitable for the sustainable growth of this sector.