Development of leading centres for mud crab aquaculture in Vietnam
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Replication of mud crab hatchery technology to sustain and expand mud crab farming practiced throughout the coastal areas of Vietnam
Until recently, all crab aquaculture in Vietnam relied on crab seed collected from the wild to stock farm ponds. However, it has been noted that further expansion of mud crab aquaculture will need an alternative source of supply, as the maximum sustainable yield from wild stocks has been reached or even exceeded in some locations. In response, the Government of Vietnam has expressed interest in the mud crab hatchery technology developed by ACIAR. It has also identified mud crab aquaculture as a priority industry for economic development.
Facilitate the timely transfer of the mud crab hatchery technology and improved mud crab farming methods from a previous project by developing ‘lead centers for crab aquaculture’ at key institutions undertaking nationally funded mud crab research programmes in Vietnam
• To upgrade hatchery facilities and staff capability at nominated lead centers in Vietnam;
• To adapt and transfer technology to local conditions and species;
• To strengthen extension capability and farmer support services; and
• To produce a hatchery manual for Scylla species.
Mud crabs can withstand salinity fluctuations and low oxygen levels, and are tolerant of some of the diseases that can devastate cultured shrimp. Mud crab farming also enables polyculture systems in which two or more aquatic species are raised together, allowing farmers to diversify their income sources. Hence, under the possible future scenario of sea-level rise in coastal areas of Vietnam, mud crab farming seems to be one of the adaptation options that enable farmers to increase their resilience to sea-level rise. The mud crab hatchery is an alternative method of supplying mud crab seeds to mud crab farmers given that the maximum sustainable yield of seeds from wild stocks has been reached or even exceeded in some locations. The hatchery is expected to sustain the saline water-resistant mud crab aquaculture.
• Research Institute for Aquaculture Nos. 2 and 3 became leading centers for mud crab aquaculture in Vietnam.
• Key project staff from partner country institutions gained valuable knowledge and experience by collaborating on larvalculture at different facilities, using alternative hatchery methodologies and culture of other Scylla species.
• Facilities at the partner institutes were upgraded to provide industry with relevant training and to allow quality RandD. Within the project, testing and upgrading of some elements of the larval rearing regime, including live feeds and water sterilization, led to improvement to the methods being used.
• Extension activities stimulated the commercial application of mud crab hatchery technology, and attracted significant government funding for the development of commercial crab hatcheries.
• Ongoing contact between staff at the centers and industry participants has stimulated feedback on further research and extension needs of the mud crab farmers.
• A number of government and private hatcheries in Vietnam have started to use the mud crab hatchery technology to rear mud crablets.
The beneficiaries from the development of leading centers on mud crab aquaculture are limited to wealthy and enterprising sectors of the communities who have the ownership of arable land and can afford to invest in mud crab culture, as crab farming is a small-scale business that has relatively modest entry requirements apart from pond infrastructure. Furthermore, there may be some adverse impacts on employment opportunities for very poor landless people.
An international mud crab hatchery manual has been produced.