The decline of Blue Swimming Crabs. What can we do about it?

Posted on 5 September 2014

Many of us tend to think of crabs as either food or perhaps something to run away from on the beach, but one thing that people might not realize is that some species of crabs provide essential livelihood opportunities for local people who have few other options to earn money.

This is true of the blue swimming crab, found in areas spanning from Southeast Asia to Australia. The blue swimming crab is considered a culinary delicacy, and a very lucrative industry has now developed around fishing them. In Thailand, blue swimming crab fisheries generated approximately 3.2 billion baht in 2011– and this figure does not include exports, which are mostly processed crab meat products.

However, the blue swimming crab has been increasingly threatened. Smaller (and younger) crab catches are being found in markets and restaurants. This is a bad sign, because if this keeps up there will not be enough young crabs to replace the old crabs, which may have a severe effect on the future growth of the crab population.

Furthermore, the recent intrusion of cockle farms onto coastal areas is depriving other economically important marine species of their natural habitat. Coastal cockle farms directly affect how many larvae are spawned and fisherman who aren’t working on the farms are having an increasingly difficult time fishing in these areas, leading to unstable income. In Thailand, most everyone involved in the blue swimming crab trade, from the fishermen to the markets, realizes that their business is becoming threatened as the resources are declining.

To take steps towards a solution, WWF invited MRAG, an independent fisheries and aquatic resource consulting company dedicated to the sustainable use of natural resources, to assess and evaluate the situation of the blue swimming crab fishing industry in Thailand using the MSC (Marine Stewardship Council) standard. Seafood with the MSC label, gives assurances to consumers that the food comes from, and can be traced back to, a sustainable fishery that meets the highest benchmarks for credible certification and eco-labelling, and adheres to the UN Food and Agriculture Organization guidelines.

Soon after MRAG made its recommendations, WWF-Thailand held a meeting with the Thai Department of Fisheries, Corporations, and Fishermen in the community. Together identified three ways to improve management of blue crab resources in Thailand:

1. Determine reference points for blue swimming crab populations using studies conducted by the Department of Fisheries and create ‘crab banks’ where eggs are grown and hatched from wild-caught crabs in tanks. This is one solution to help return Thailand’s blue swimming crab population to a healthier level, and once the young crabs are of a certain size, they are released back into the ecosystem.
2. Ensure that blue swimming crab fisheries do not negatively affect marine ecosystems, especially endangered and threatened species such as sea turtles and dugongs.
3. Ensure Thai law prohibits fishing for blue swimming crabs during the spawning season from October to December each year, allowing the crab population to recover.

It is hoped that in working together with the Thai Department of Fisheries, Corporations, and Fishermen, WWF-Thailand can have the same successes as WWF-Vietnam. WWF-Thailand started the Blue Swimming Crab Fishery Improvement Project (BSC FIP) in 2012 and is supported by WWF-US , National Fisheries Institute (NFI) Crab Council and TFFA(Thai Frozen Food Association)/TCPG (Thai Crab Processer Association). WWF-US and WWF-Vietnam provided technical and financial support for the design of a Fishery Improvement Project (FIP)

WWF-Thailand has just finished two successful consultation meetings concerning the launch of a blue swimming crab FIP in Thailand. The meetings were comprised of key stakeholders from Thailand’s Department of Fisheries, big corporations, academics, NGOs and fishermen who realize that the natural habitat is under threat and that the crab population has declined dramatically. An action plan workshop in Surat Thani province will soon take place to finalize where the project site will be, which is expected to be located in Ban Don Bay, an important habitat where the blue swimming crab is under severe threat.

“We need to monitor and document crab banks and need the support on the policy level to define a specific species management plan in order to allocate finances to support the groundwork,” said Kritsana Kaewplang, WWF-Thailand’s Sustainable Markets Project Manager. “I found that with all parties working together, which includes the researchers, corporations, the provincial Department of Fisheries staff, and the local fishermen, we collectively have very good ideas and are really keen to do the work. Issues are raised and discussed. This meeting definitely brings hope to the community. It is challenging, but together we can make the necessary changes.”