Researchers have designed SmartRAS, a Recirculating Aquaculture System aimed specifically for precision broodstock management. Unlike traditional reliance on wild-caught crabs, SmartRAS provides a controlled, temperature-optimized environment that conditions immature adult crabs to reach maturity with enhanced reproductive performance. By producing quality broodstock under these carefully managed conditions, hatcheries can achieve more consistent and reliable seed production.
The Philippines is one of the world’s top producers of mangrove crabs. It continues to supply both local and international markets with live crabs. However, despite the strong demand, the industry is facing challenges with poor broodstock performance, which leads to inconsistent larval quality in hatcheries. Most seedstocks still come from the wild, creating sustainability concerns and unpredictable broodstock quality.
Traditional broodstock management systems often record low survival and spawning success rates, typically falling below 40%. SmartRAS addresses this through a polychaete-assisted biofilter that naturally improves and stabilizes water quality. Combined with optimized temperature control, this feature targets significant reduction in stress among broodstock, leading to improved reproductive performance.
The project, “Optimization of temperature for Scylla serrata broodstock in a recirculating system with a polychaete-assisted biofilter,” initially developed a modified RAS. Funded by the Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development of the Department of Science and Technology (DOST-PCAARRD), the project generally aims to enhance the performance of S. serrata broodstock through further refinement of the management techniques by determining optimum temperature. This was implemented by Mindanao State University-Iligan Institute of Technology, led by Dr. Mercedes M. Pates.
Project results showed that survival, spawning, and hatching rates were higher using modified RAS than with the conventional system. The system consistently maintained lower ammonia and nitrite levels which signals better water quality. Broodstock reared at 27°C consistently exhibited the highest survival, spawning, and hatching rates, suggesting that this temperature provides the most favorable conditions for mangrove crab broodstock.
By compartmentalizing the tank, this modified RAS design effectively reduced cannibalism, a common issue in crab culture, leading to higher survival rates. Larvae produced in the RAS environment were healthier and of better quality compared to those from conventional systems.
The modified RAS was further improved through an ongoing DOST-PCAARRD-funded project, “Enhancement of captive Scylla serrata broodstock performance through optimization of light conditions and application of nanobubble oxygenation.” The findings from this study will complete the data needed to finalize the SmartRAS concept. Once all parameters are incorporated into the system, SmartRAS will be fully developed as an integrated, technology-enabled platform for optimized broodstock conditioning.
The system is equipped with real-time monitoring tools that track pH, dissolved oxygen, ammonia, and nitrite through a cloud-based dashboard. An AI-driven guided response system allows hatchery operators to do remedial measures quickly to any changes, ensuring healthier crabs with less manual monitoring. SmartRAS is also cost-efficient with higher broodstock survival and increased production potential.
The technology was also featured during the National Science, Technology, and Innovation Week 2025 at Laoag City, Ilocos Norte with various local government units, public and private institutions expressing interest.
Currently, SmartRAS is still in the development stage and further refining its key features. Hopefully, soon it will provide a stable supply of quality broodstock, reduce dependence on wild-caught crabs, and strengthen the sustainability and competitiveness of the Philippine mangrove crab industry.