Strengthening a blue economy after habitat loss: assessing anti-trawling structures and small-scale fisheries impacts in Cambodia’s Mission Blue Hope Spot

This study introduces the potential of fisheries productivity structures (FPSs), as passive conservation infrastructure, to enhance habitat recovery and sustainable small-scale fisheries. The Cambodian coastline is devastated by illegal unregulated fishing activities and lacks reliable historical data, complicating monitoring and conservation efforts. By providing the only comprehensive benthic distribution data for the region, this study supports the placement of anti-trawling FPSs within the protected Kep Marine Fisheries Management Area (MFMA), in order to support these sustainability strategies for widespread future use. A grid survey was conducted across four survey zones at 250 m intervals covering 62,146 ha: 1) Kep MFMA, 2) Outer Kep, 3) Kampot, and 4) Koh Seh. These data are the first documentation of habitat decline in the region, showing a 39% reduction in seagrass coverage in Kampot between 2013 and 2023. Trawling destroys benthic habitats in areas deep enough for trawling vessels to operate, but in areas protected by FPSs, seagrasses were observed to persist at trawler-accessible depths. Further, observations of seagrass regrowth near FPSs indicate recovery and possible fisheries benefits. Ongoing monitoring will be necessary to document productivity trends in response to FPS implementation. Our results demonstrate that FPSs show early signs of supporting seagrass recovery and offer a scalable, low-cost conservation tool that could support blue economies, not only in Southeast Asia, but also in other coastal regions facing similar challenges.