A version of this article originally appeared on GEF:IWlearn.
Mangrove crabs (Scylla serrata, also known as mud crabs) are some of the most valuable crab species in the world. Considered a delicacy in many parts of Asia, they fetch a high price at the market, providing a strong incentive for local communities to harvest them. Indeed, the crabs are Madagascar’s third most valuable seafood export. Moreover, 75% of Madagascar’s mud crabs are exported, while the remaining crabs are consumed locally.
The demand is high resulting to a decline in the mud crab population in many parts of Madagascar, including the Sofia Region, where production has decreased 25% between 2017 and 2019 alone. Part of the decline may be related to the degradation of the mangroves themselves, which have decreased by 24% between 1995-2018. In addition to providing a host of ecosystem services – like preventing shoreline erosion, providing nursery areas for marine life, supporting food and job security – mangroves also provide both shelter and food for these mud crabs.
Additionally, the drop-off could be due to overeager harvesters plucking under-sized crabs and selling them at market, which is against regulations in Madagascar designed to ensure the crab stocks are able to replenish themselves.
In any case, the rapid decrease in both mangroves and mangrove crabs can be destabilizing to the local communities living around these mangrove forests, who have become dependent on the crabs as a source of food and income. To address the problem, the Nairobi Convention, together with the Direction Générale de la Pêche et de l’Aquaculture of Madagascar, is implementing a demonstration project to improve governance of fishing resources (i.e. the mangrove crab) in ten villages in the Sofia region.
In each of the ten villages, local management plans will be developed to ensure the sustainable exploitation of the mangrove crab, plans that will include initiatives like the “professionalization” of small-scale fishing through the creation of fishers’ associations, boat registration, and fisher identity cards. Such measures will then make it easier to establish and run a community-based monitoring system for crab catches, also envisaged under the plan, to ensure that all fishers are adhering to sustainable use guidelines.
Project implementers will also install crab holding systems, whereby the crabs are held in ponds or pens for fattening. The heavier crabs can then be sold for a much higher price at market than if they were sold immediately after capture. Villagers will be trained on the appropriate holding techniques to ensure the long-term success of the holding systems.
Not only does this create an alternative livelihood option to the direct fishing of crabs, but crab populations will also be able to rebound more quickly thanks to the reduced pressure. In this way, project implementers are hoping to make villages in the Sofia region more resilient by ensuring a steady stream of income and food. At the same time, the project will help maintain the natural functioning of the mangrove ecosystem.
In this way, the project will not only help Madagascar achieve its targets under Sustainable Development Goal (SDG) 14, “Life Under Water”, in which it committed to protecting marine and coastal ecosystems, but also help it achieve SDG Goal 2 on Zero Hunger and Goal 8 on Employment.
The initiative is funded by the Global Environment Facility through the Western Indian Ocean Large Marine Ecosystems Strategic Action Programme Policy Harmonization and Institutional Reforms (SAPPHIRE) project, executed by the Nairobi Convention and implemented by UNDP.
The project promotes policy and institutional reform to help improve the management of the Western Indian Ocean. The Convention, part of the United Nations Environment Programme’s Regional Seas programme, serves as a platform for governments, civil society and the private sector to work together for the sustainable management and use of the Western Indian Ocean’s marine and coastal environment.
For more information and updates on the project, click here.
Cover Photo: Beth Watson/Ocean Image Bank