Illegal, Unreported, and Unregulated Fishing in the South China Sea

The South China Sea (SCS), a strategically vital maritime region, faces a profound ecological and legal crisis in the form of illegal, unreported, and unregulated (IUU) fishing. As one of the world's most biodiverse marine ecosystems, the SCS plays a critical role in food security and economic livelihoods for millions. However, overfishing, inadequate governance, and geopolitical tensions have made IUU fishing a significant challenge. This article examines the issue through a legal lens, focusing on the causes, consequences, and possible legal solutions under international and regional frameworks.

The Geopolitics in the South China Sea

The SCS spans approximately 3.5 million sq.km. and contributes over 12% of the global fish catch annually. The SCS is one of the most contested regions in the world, marked by overlapping sovereignty claims by six major stakeholders: China, Vietnam, the Philippines, Malaysia, Brunei, and Taiwan. These disputes are rooted in strategic interests, as the SCS provides access to significant fishing grounds, mineral resources, and strategic waterways that connect the Pacific and Indian Oceans.

Central to the geopolitical conflict is China’s claim over nearly 90% of the SCS, delineated by the controversial “nine-dash line”, which the 2016 Permanent Court of Arbitration under the United Nations Convention on the Law of the Sea (UNCLOS) ruled as having no legal basis. Despite the ruling, China continues to assert jurisdiction over vast areas, creating challenges for implementing effective fisheries governance. The dispute escalates further with China's activities, including land reclamation and the militarization of artificial islands, which have been met with strong opposition from other claimants and the international community.

IUU Fishing in the South China Sea

Illegal, unreported, and unregulated (IUU) fishing poses one of the most severe threats to the marine ecosystem and the livelihoods of millions of people reliant on fisheries. In the context of the SCS, IUU fishing encompasses activities that violate domestic and international laws, such as fishing in prohibited areas, using destructive methods, or failing to report catches.

Illegal fishing involves activities that breach national laws or international obligations. In the SCS, many incidents involve fishing vessels operating within another nation’s Exclusive Economic Zone (EEZ) without authorization. China’s maritime militia, which operates under civilian guise but receives support from Beijing, is frequently implicated in such activities. These vessels not only exploit resources but also serve as tools for asserting territorial claims.

Unreported fishing refers to activities that are not declared to relevant authorities, making it difficult to monitor and manage marine resources effectively. China’s distant-water fishing fleet, the largest in the world, has been criticized for underreporting its catch, often by a factor of 12. This lack of transparency exacerbates overfishing and depletes already strained fish stocks.

Unregulated fishing typically occurs in areas where governance is weak or absent. In the SCS, this includes high seas and disputed waters where enforcement mechanisms are undermined by overlapping sovereignty claims. This vacuum enables large-scale exploitation by distant-water fleets, further threatening marine biodiversity.

Key Drivers of IUU Fishing

• Overlapping Sovereignty Claims

The SCS’s overlapping maritime claims create a legal vacuum that allows IUU fishing to thrive. Countries use fisheries as tools for asserting sovereignty, with China’s maritime militia playing a particularly controversial role. These civilian vessels, reportedly trained and funded by the Chinese government, often escalate disputes by encroaching on the EEZs of other nations.

• Depleting Fish Stocks

The SCS’s fish stocks have declined by 70–95% since the 1950s due to overfishing, pollution, and habitat destruction. With fish serving as a critical protein source for millions in the region, this depletion drives desperate measures, including IUU fishing.

• Economic Pressures

The fishing industry is vital to the livelihoods of coastal communities and national economies. In China alone, the sector employs over 14 million people. Subsidies for fuel, gear, and vessel construction incentivize aggressive fishing practices, exacerbating the problem.

• Weak Governance and Enforcement

Many SCS littoral states lack the resources to enforce fisheries regulations effectively. The absence of coordinated regional governance mechanisms further undermines efforts to curb IUU fishing.

Consequences of IUU Fishing

• Environmental Impact

IUU fishing severely disrupts marine ecosystems. Practices such as bottom trawling and the use of illegal nets destroy coral reefs and deplete populations of endangered species like giant clams and sea turtles.

• Economic Losses

Legitimate fishers face declining incomes as IUU fishing undermines sustainable practices. Coastal economies dependent on fisheries suffer significant financial losses.

• Geopolitical Tensions

Fishing incidents often escalate into diplomatic disputes. For example, the 2019 ramming of the Philippine fishing vessel Gem-Ver 1 by a Chinese ship strained bilateral relations and underscored the link between IUU fishing and regional instability.

Legal Frameworks for Addressing IUU Fishing

• UNCLOS Provisions

UNCLOS provides the foundation for maritime governance, outlining rights and responsibilities in EEZs and high seas. Article 61 mandates coastal states to conserve living resources, while Article 123 encourages cooperation in semi-enclosed seas like the SCS. However, enforcement is hindered by sovereignty disputes and the lack of compliance mechanisms.

• The Port State Measures Agreement (PSMA)

The PSMA is the first binding international agreement specifically targeting IUU fishing. It requires port states to deny entry to vessels engaged in illegal activities. While China has signed the PSMA, its implementation has been inconsistent, reflecting the challenges of translating international commitments into domestic action.

• Regional Mechanisms

ASEAN’s efforts to establish a regional fisheries management organization have been stymied by geopolitical complexities. Bilateral agreements, such as those between Indonesia and Vietnam, offer some promise but lack the scope to address the broader regional crisis.

Recommendations for Combating IUU Fishing

• Strengthening Regional Cooperation

Given the SCS’s contested nature, functional cooperation offers a pragmatic solution. Joint fisheries management, shared surveillance systems, and coordinated enforcement could help diffuse tensions while protecting marine resources.

• Enhancing Legal Enforcement

States must align their domestic laws with international frameworks such as UNCLOS and IPOA-IUU. Investment in satellite-based vessel monitoring systems and real-time data-sharing platforms can bolster enforcement capacity.

• Promoting Sustainable Practices

Encouraging aquaculture and diversifying income sources for fishing communities can reduce dependence on wild capture fisheries. Education campaigns and incentives for sustainable practices are equally important.

• Holding Distant-Water Fleets Accountable

The international community must increase scrutiny of distant-water fleets, particularly those operating under weak regulatory oversight. Transparent reporting and adherence to global norms are essential.

• Involving Non-State Actors

NGOs, local fishing communities, and international organizations can play a pivotal role in advocacy, capacity building, and monitoring compliance.

Conclusion

Addressing IUU fishing in the South China Sea requires a multi-faceted approach that integrates legal, environmental, and political solutions. While the challenges are significant, the opportunities for collaboration are equally promising. Strengthening regional cooperation, enforcing international legal frameworks, and promoting sustainable fishing practices are essential steps. As the largest stakeholder, China’s role will be pivotal. By aligning its domestic policies with international norms and engaging in regional efforts, China could lead the way in transforming the SCS into a model for sustainable fisheries management. Ultimately, a unified approach grounded in legal principles and mutual trust is the key to preserving the South China Sea’s ecological and economic integrity for future generations.

References

Chengyong Yu, Yen-Chiang Chang, China’s Incentives and Efforts against IUU Fishing in the South China Sea, 15(9) Sustainability 7255 (2023) https://doi.org/10.3390/su15097255

Zhang, H., The South China Sea fishing crisis: the overlooked role of Chinese subnational governments, 37(6) The Pacific Review 1090, (2024) https://www.tandfonline.com/doi/abs/10.1080/09512748.2024.2304805

Commander Jennifer Runion, Fishing for trouble: Chinese IUU fishing and the risk of escalation, U.S. Naval Institute, (2023) https://www.usni.org/magazines/proceedings/2023/february/fishing-trouble-chinese-iuu-fishing-and-risk-escalation#:~:text=Coast%20Guard-,Fishing%20for%20Trouble%3A%20Chinese%20IUU%20Fishing%20and%20the%20Risk%20of,information%20sharing%20with%20partner%20nations. (Accessed: 27 January 2025).

The author affirms that this article is an entirely original work, never before submitted for publication at any journal, blog or other publication avenue. Any unintentional resemblance to previously published material is purely coincidental. This article is intended solely for academic and scholarly discussion. The author takes personal responsibility for any potential infringement of intellectual property rights belonging to any individuals, organizations, governments, or institutions.