Special report: Marine conservation in Cambodia: hopes and threats for a sustainable future

The Cambodian coast, cradle of a unique marine biodiversity, is facing one of its greatest challenges: the accelerated degradation of its coastal habitats. Seagrass meadows, coral reefs and bivalve beds are key ecosystems, ensuring not only ecological balance but also the economic survival of many local communities.

Yet these precious environments are suffering dramatic loss, directly linked to destructive fishing and cumulative environmental pressures, jeopardising Cambodia's natural wealth and blue future.

Devastation caused by destructive fishing

The picture is alarming: illegal fishing, bottom trawling, dynamite and cyanide fishing are all having devastating impacts. Commercial trawling, banned in waters less than 20 metres deep, nevertheless continues to ravage the seabed, destroying the benthic habitats essential to marine fauna.

This technique also increases turbidity in the water, depriving seagrass beds and corals of the vital light they need to photosynthesise, and making these ecosystems even more fragile. As a result, fish biomass is declining, affecting small-scale traditional fishermen whose livelihoods depend closely on the health of the sea.

Community initiatives and the fight for protection

Faced with this crisis, committed players such as Marine Conservation Cambodia (MCC) are working to reverse the trend. The blue economy model, long based on small-scale sustainable fishing practices, is being undermined by the intensification of illegal activities. MCC played a crucial role in the creation of the Kep Marine Fisheries Management Area (MFMA), a marine protected area where destructive fishing is limited and only small-scale activities remain, protected by innovative structures.

Anti-spawning structures: a promising solution

Among the tools used, Fisheries Productivity Structures (FPS) appear to be an innovative and appropriate response. These concrete structures, installed underwater, prevent bottom trawling nets from ravaging fragile habitats.

Their effectiveness has been noted in the Kep region in particular, where they encourage the regeneration of seagrass beds and improve the catches of local fishermen. These results offer tangible hope, not only for Cambodia, but also for other coastal regions facing the same scourge.

A ground-breaking study of benthic habitats

A recent study of more than 62,000 hectares along the Cambodian coast has produced the first rigorous inventory of seagrass beds, coral and bivalve beds. The results are striking: a 39% drop in seagrass coverage in Kampot between 2013 and 2023, underlining the urgent need for action. However, in the areas protected by the FPS within the Kep MFMA, signs of regeneration are appearing, confirming the positive impact of these structures.

Depth and substrate type: determining factors

Benthic habitats are strongly influenced by the depth and nature of the seabed. Seagrass beds are mainly found in shallow waters, where trawlers cannot operate. Where FPSs are deployed, these meadows are even found at greater depths, a sign of ongoing restoration. At the same time, muddy sediments have a pronounced negative effect by reducing water clarity and available light, which are essential for photosynthesis in seagrass beds.

An exceptional wealth of biodiversity

Cambodia is home to a remarkable diversity of seagrass beds, with at least ten species recorded in the region, including Thalassia hemprichii and Enhalus acoroides. This richness is comparable to that of the most complex ecosystems on the planet, making the area a marine biodiversity hotspot. However, this diversity is fragile and depends directly on effective conservation measures.

Towards a sustainable blue economy

This research highlights that the sustainability of Cambodia's blue economy depends on the protection and restoration of coastal habitats. In addition to their ecological value, seagrass beds are essential carbon sinks in the fight against climate change, capable of storing large quantities of CO2. Preserving them is therefore an environmental, economic and climate issue that is crucial to national objectives.

Outlook and commitments

To combat illegal trawling, we need to step up our efforts to monitor and manage marine protected areas. Continued deployment of FPSs, combined with better integration of local communities in monitoring and management, is at the heart of the recommended strategies. By multiplying these approaches on a regional scale, Cambodia can become a model for Southeast Asia and beyond, demonstrating that pragmatic, local conservation can coexist with a thriving marine economy.

Collective mobilisation

Finally, the commitment and support of local communities are key to this success. Fishermen themselves approve of and participate in conservation initiatives, recognising that their very survival depends on safeguarding marine ecosystems. This bottom-up partnership between local players and experts shows the way forward for protecting these marine treasures while ensuring the food and economic security of coastal populations.