CFI Indonesia promotes sustainable mangrove crab management

26 Nov 2025 | by m-duque@unesco.org
Efforts to advance sustainable mangrove crab fisheries in Southeast Maluku Regency continue to be strengthened. The Global Environment Facility (GEF-6) Coastal Fisheries Initiative (CFI) Indonesia program facilitated a meeting of the Working Group (Pokja) for the Marine Stewardship Council (MSC) Mangrove Crab for the Hoat Sorbay Bay area. The meeting marked an important step in expediting the process toward achieving MSC certification for Southeast Maluku’s mangrove crab fishery, a global standard for sustainable fisheries.

The event, held at Hotel Santika Ambon, was attended by 30 participants representing local government, academia, non-governmental organizations, fishers’ groups, as well as development partners such as WWF Indonesia and the Project Management Unit (PMU) of GEF-6 CFI Indonesia. Key officials were also present, including the Head of the Marine Affairs and Fisheries Office (DKP) of Maluku Province and the Head of Fish Quarantine, Quality Control and Fishery Products Safety (KIPM).

Balancing Economic Gains and Sustainability

In his speech, Erawan Aiskin emphasized the importance of maintaining a balance between increasing fishers' income and preserving crab stocks in the wild. He noted that market demand—particularly from export buyers—cannot yet be fully met due to limited stock and the inconsistency of catch sizes with required standards.

“Fishers must be able to meet buyers’ standards without compromising stock sustainability. Proper management of fishing areas and seasons is essential to ensure fishers’ income remains stable,” he said. Aiskin also encouraged all participants to contribute to improving the performance indicators required for MSC certification, so that the Southeast Maluku mangrove crab fishery can gain international recognition as an environmentally friendly and sustainable fishery.

Scientific Presentation: Status of Mangrove Stocks in Hoat Sorbay Bay

During the discussion session, Kamaluddin Kasim, a researcher and resource person for the MSC Mangrove Crab Working Group, presented research findings on the population status and management of mangrove crabs in Hoat Sorbay Bay. Based on the Decree of the Head of the Maluku Provincial Marine and Fisheries Office (DKP), the minimum catch size has been formally established and agreed upon.

Kamaluddin explained that marine crabs remain relatively abundant, but land crabs show signs of population decline due to intensive harvesting. “Land crabs are more vulnerable because their habitat is limited and they are often caught before reaching gonadal maturity,” he noted.

Stock analysis conducted from 2020–2024 shows that Scylla serrata maintains biomass levels above the sustainable threshold (B/BMSY > 1), while S. olivacea falls below the safe limit (B/BMSY < 1; F/FMSY > 1.4). The Schaefer surplus production model indicates maximum sustainable yield (MSY) potentials of 1,940 tons for S. serrata and 1,257 tons for S. olivacea. This means that annual production should not exceed these values to allow natural stock recovery.

The Length-Based Spawning Potential Ratio (LBSPR) analysis further reveals that many crabs are being caught before having the chance to reproduce—particularly S. olivacea, which has an SPR value below 0.25. Meanwhile, S. serrata shows slightly better results (SPR 0.28–0.38), though still below the ideal conservation threshold (≥0.40).

Working Group Agreement: Harvest Rules and Habitat Protection

The Working Group meeting produced a Record of Agreement that serves as guidance for fishers, collectors, and buyers to support the sustainablility of crab resources. Key points of the agreement include:

  • Recommended minimum catch sizes:
    • S. serrata: 15 cm carapace width or at least 600 grams
    • S. olivacea: 14 cm carapace width or at least 400 grams
  • Egg-bearing female crabs must be released back into the wild
  • Harvesting is prohibited in Bidubloat (Ohoi Evu) and Ohoi Warwut areas to protect spawning grounds
  • Updating of the Maluku Provincial DKP Decree on crab size and weight restrictions
  • Recommended annual catch quotas: 1.94 tons for S. serrata and 1.25 tons for S. Olivacea
  • An annual meeting of the Mangrove Crab Working Group will be held to monitor stock conditions and management strategies

These measures form part of the proposed Harvest Strategy and Harvest Control Rule (HCR), which are developed based on research findings. The strategy includes regulating size limits, restricting the types of fishing gear, implementing temporary closures during spawning seasons, and monitoring mangrove habitats that serve as critical nursery grounds for juvenile crabs.

Model simulations indicate that increasing the average size limit by 5–10% can raise the Spawning Potential Ratio (SPR) to above 0.50, thereby improving the likelihood of natural reproductive success. In this way, the strategy not only protects crab stocks but also supports economic sustainability for coastal communities that depend on these resources.

Towards MSC Certification and the Future of Sustainable Fisheries

The MSC Mangrove Crab Working Group meeting in Hoat Sorbay Bay is part of the broader journey toward achieving Marine Stewardship Council (MSC) certification. This certification indicates that a fishery meets global standards for sustainable resource management, minimal ecosystem impact, and transparent management systems.

Through collaboration among government, fishers, academics, and development partners, the management of mangrove crab fisheries in Southeast Maluku is expected to become a model of sustainable fisheries in Eastern Indonesia. With the application of scientific principles and active community participation, the balance between ecological conservation and economic well-being is no longer just an aspiration but a tangible future for the coastal regions of Maluku."

About the project

CFI Indonesia, through the GEF-6 grant titled "The Ecosystem Approach to Fisheries Management (EAFM) in Eastern Indonesia (Fisheries Management Area - FMA 715, 717, & 718) Components A, B, and D", is a collaboration between Indonesia’s Ministry of Marine Affairs and Fisheries (KKP) as the implementing agency and the WWF GEF Agency as the managing institution. This initiative, which began on December 23, 2019, and is scheduled for completion on December 31, 2026, aims to strengthen sustainable coastal fisheries management in the FMA 715, 717, and 718 regions.

Amid growing efforts to promote sustainable fisheries in Eastern Indonesia, CFI Indonesia strengthens ecosystem-based management through the Mangrove Crab Fishery Improvement Program in Teluk Hoat Sorbay, Southeast Maluku. Supported by the Global Environment Facility (GEF-6) and implemented by the Ministry of Marine Affairs and Fisheries (KKP) in collaboration with the WWF GEF Agency, this initiative facilitates the Marine Stewardship Council (MSC) Working Group for Mangrove Crab, a key step toward achieving international certification for sustainable fisheries. Through scientific assessments, stakeholder coordination, and participatory management, the program helps align local practices with global standards — ensuring that harvesting activities remain within sustainable limits while protecting mangrove habitats and spawning areas. By integrating harvest strategies, size limits, and seasonal closures, the initiative aims to rebuild crab stocks, maintain ecosystem balance, and improve the livelihoods of small-scale fishers. The process also empowers local institutions to take ownership of resource management, setting the foundation for a transparent, science-based, and community-driven pathway toward MSC certification and a resilient coastal economy in Maluku Tenggara.

For more information, please contact [Marsha Maritza]: [mrshmaritza@gmail.com].

Words by Ahadar Tuhuteru and Marsha Maritza.