Humble though they may be, sea cucumbers fulfill important ecological roles. They are prey for fish and other animals, especially as eggs or larvae, and hosts to a range of smaller animals that live inside their bodies. Their ecosystem function is similar to that of earthworms on land: they consume sediment and recycle nutrients back into the food web. A 2011 study showed that sea cucumbers’ feeding and excretion increase seawater alkalinity, contributing to local buffering of ocean acidification.

Sea cucumbers may also have untapped pharmaceutical value. Steve Purcell, a sea cucumber expert at the National Marine Science Centre at Southern Cross University in Australia, points to recent studies looking into the potential utility of sea cucumber compounds for treatments like anti-cancer and anti-coagulant drugs. ”So it’s important because of that, that we maintain healthy populations of breeding animals because we are going to need them in the future for drugs,” Purcell says.

Around the world, fishing pressure for the pharmaceutical industry, and to a greater degree the food industry, are causing problems for sea cucumbers. “Worldwide we are already seeing a lot of documented local extinctions. We know from surveys now that in some places species have just disappeared. Maybe a few of them are still there but certainly not in populations that could be considered biologically or ecologically viable,” Purcell says.

Stronger national regulation of sea cucumber harvests would help, he says. “If fishing was restricted to fewer and just mature adults, fishers could make a living whilst conserving a renewable resource for the future,” he says.

He also calls for international regulation of the sea cucumber trade. In August 2019, CITES member countries accepted a proposal to include the first three species of sea cucumber on Appendix II, with a 12-month delay in implementation. To trade the three species internationally, governments will have to issue export permits after ensuring that the trade will not impair the survival of the species in the wild. Purcell said he applauds the move and thinks CITES could consider adding other species to encourage better fisheries management. Yet achieving CITES protection is not simple. Without good field data on wild population numbers, it’s difficult to demonstrate the extent of decline, a requirement for CITES listing.

Madagascar’s fisheries management undoubtedly needs drastic improvement if the sea cucumber fishery is to stand any chance of recovery, says Adrian Levrel, an independent marine and coastal resources management specialist based in Madagascar. Currently there is no official closure or quota system in place to limit the amount of sea cucumbers exported. The lack of stock assessment figures impedes the development of a national management plan.

Moreover, some of the measures that do exist don’t account for the biology or biological diversity of Malagasy sea cucumbers, Levrel says. By way of example he points to a law, Arrêté nº 525, that defines the minimum size of sea cucumbers that can be legally harvested or sold: 11 cm (4.3 inches) when fresh, and 8 cm (3.1 inches) when dried. “What these restrictions don’t take into account, however, is that we have around 30 species of sea cucumber that are commercially harvested here in Madagascar, which can vary greatly in length once they have reached maturity,” Levrel says. “This law is largely ineffective, as it fails in particular to protect the immature individuals of the most targeted species, including Holothuria scabra.”

Even if the government were to develop a rigorous management plan, one that fishers like Tahiry bought into, protecting such a profitable resource is difficult in Madagascar. Opportunists with no interest in a long-term viable fishery are always drawn to black markets where the risk of prosecution is low and the financial rewards are large.

Silvy Raharimalala is the director of fisheries for Diana, Madagascar’s northernmost region, where Nosy Be is located. Raharimalala describes the difficulty she and her colleagues face enforcing the law. “The numbers of sea cucumbers have declined a lot since I first started in 1995, but we simply don’t have the resources, manpower or finances to effectively patrol our waters,” she says. Madagascar, the world’s fourth-largest island, has a coastline of more than 4,800 kilometers (3,000 miles) and one of the biggest marine territories in the Indian Ocean. “Even if we get tip-offs of illegal activity we can’t compete with the big bosses who finance these operations. Their boats are faster than ours, so as soon as they see us they disappear,” Raharimalala says.

Corruption is another factor, according to Ndranto Razakamanarina, president of Alliance Voahary Gasy, a network of Malagasy environmental groups. “Madagascar is one of the most corrupt countries in the world and it happens in every sector and at every level,” he says. In 2019, Transparency International listed Madagascar at 158th out of 180 countries when it comes to public sector corruption.

“In order to preserve the species, it’s forbidden to fish for sea cucumbers with dive materials. Unfortunately, however, the laws here are not applied to everyone and it is only low-level people who are doing their best to survive who are being arrested,” Razakamanarina says angrily. “Those who are sitting up at the top tables of this illegal trade are going unprosecuted … The government care more for their foreign investors than they care about fishing communities.”

I spoke with “Hery,” an environmental activist who requested a pseudonym for fear of retaliation. He said he has seen firsthand the scale of the illegal sea cucumber trade. “It’s a huge operation and it’s just not sea cucumbers that are being smuggled out,” he says. “You’ve got shark fins, you have tortoises, you have eels and hardwood.”

Transshipment at sea, as the practice of moving cargoes between ships offshore is called, can be legal. But it is often a means to circumnavigate fisheries laws. It and other illegal, unreported and unregulated (IUU) fishing practices not only deplete Madagascar’s waters but also deprive the country of taxable revenue and fishers of vital incomes.

Sea cucumbers being processed, before sale to local buyers. Image by Michel Strogoff / © Chris Scarffe Film and Photography.

Despite all those challenges, there are some glimmers of hope. One is community sea cucumber aquaculture programs in a few villages in southwestern Madagascar. These are attempting to provide a new form of income for traditional small-scale fishers and to alleviate pressure on local wild sea cucumbers and other marine organisms. Having begun in 2008, organizers say the pens are finally starting to produce well. Even so, the aquaculture model will require careful development and expansion if it is to play a significant role nationally. (One of the main organizers, the NGO Blue Ventures, is an occasional client of mine.)

Another glimmer came earlier this year, when the Ministry of Agriculture, Livestock and Fishing announced that it had received funding from the World Bank to carry out a resource stock assessment of sea cucumbers in Malagasy waters. If the COVID-19 pandemic permits it to happen this year, as planned, it would represent the first step toward drafting a national management plan for the sea cucumber fishery. And that would represent a first step toward recovery for Madagascar’s sea cucumbers.

Meanwhile, fishers like Tahiry continue to risk their lives by diving farther and deeper offshore to find the last remaining wild populations of these sought-after echinoderms.

Holothuria fuscogilva, one of the first three species of sea cucumber to be included on Appendix II of CITES, which regulates international trade. Image by Frédéric Ducarme via Wikimedia Commons (CC BY-SA 4.0).

Banner image: Sea cucumbers await processing in northwest Madagascar. Image by Michel Strogoff / © Chris Scarffe Film and Photography.

Chris Scarffe is an independent filmmaker, photographer and writer who specializes in environmental and wildlife related content. See his work at


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