By Dr Nirmal Shah
They may be the “ugly ducklings” of the sea, but sea cucumbers are the unsung heroes of our marine world. Far from being mere lumps on the ocean floor, these fascinating creatures are essential ecosystem engineers. Much like earthworms on land, they tirelessly recycle nutrients, clean sediments, and process organic matter. By doing so, they maintain the delicate function of coral reefs, keeping the “living machinery” of the ocean productive and resilient.
A Global Appetite for “Bêche-de-Mer”
With over 1,700 species spanning from sun-drenched shallow reefs to the crushing depths of the abyss, sea cucumbers are incredibly diverse. However, roughly 80 species are caught in a high-stakes global trade. Marketed internationally as bêche-de-mer, they are a prized luxury in Asian cuisine and a staple of traditional medicine. While this export fishery supports the livelihoods of many coastal communities, it is a double-edged sword. Because sea cucumbers grow slowly and are exceptionally easy to harvest, they are highly vulnerable to overexploitation.
The Cycle of “Contagious” Depletion
In a landmark status update recently published by my old friend Chantal Conand, the world’s most renowned sea cucumber expert and her colleagues, the news for these invertebrates is sobering. The study reveals a pattern of exploitation that is both “serial” and “contagious.”
Rather than focusing on long-term sustainability, the industry often operates in a cycle of rapid expansion: Fisheries move into a new region, high-value stocks are quickly depleted, the operation shifts both geographically to new waters and biologically to different species.
Despite a brief pause during the COVID-19 pandemic, global catches remain alarmingly high, averaging over 90,000 tonnes annually. As high-value species disappear, the footprint of the industry continues to push into untouched areas and obscure species.
The Challenge
The core issue lies in how the sector is structured. Most sea cucumber fisheries are small-scale and involve multiple species. They are often weakly regulated, making it incredibly difficult for authorities to manage them effectively or enforce rules consistently. The result? A globalized pattern of depletion that leaps from one fishery to the next.
Spotlight on Seychelles: A Legacy at Risk
In Seychelles, sea cucumber harvesting is a tradition dating back to the 1800s. For centuries, it remained a modest activity until the late 1990s. Surging international demand and skyrocketing prices sparked a major intensification of the local fishery. Managed by the Seychelles Fishing Authority (SFA), the fishery has not yet collapsed, but it is far from healthy. The data points toward a worrying trend. Effort is increasing but rewards are decreasing. In other words the fishers are working harder but productivity is declining. The fishery has become dangerously dependent on a single species, the Flower Teatfish (Pentard). If the Flower Teatfish population falters, the entire sector could face a sudden downturn.
What’s next?
The science clearly shows that we cannot continue to treat sea cucumbers as an inexhaustible resource. To prevent total depletion, we need stronger controls in the form of stricter quotas and seasonal closures. It is clear that better data is needed by real-time monitoring of catch sizes and species health. Adaptive management needs to be adopted by putting in place management strategies that can pivot quickly as stock levels change.
Without a shift toward sustainability, we risk losing not just a valuable export, but the very engineers that keep our reefs alive.
Global sea cucumber fisheries: an update for the last decade
Top photo: Flower Teatfish (Pentard) - Source - Seychelles Nation