INTRODUCTION
Oceans comprise more than 70% of the Earth and are home to marine biodiversity that contributes to the Earth’s global ecosystem, such as oxygen, carbon sequestration, food security to the billions, and discoveries in pharmaceuticals due to genetic resources, but with climate change, the biodiversity faces an existential threat due to anthropogenic activities such as overfishing, plastic pollution, deep-sea mining, and ocean acidification. Out of the ocean surface, areas beyond national jurisdiction (ABNJ), including the high seas and the seabed Area, are almost 64 per cent, and are controlled by disjointed regimes that value freedoms over conservation (resulting in loss of biodiversity in greater proportions than has ever been seen in human history). The United Nations Convention on the Law of the Sea (UNCLOS) initiated international law in 1982 since then applies Articles 192 and 194 have been applied to compel states to conserve and protect the marine environment and collaborate, though there remain many gaps in the regulation of the high seas since then, which has led to calls to adopt comprehensive instruments such as the 2023 BBNJ Agreement.
This research paper critically examines the effectiveness of UNCLOS as the foundation of ocean governance, which is complemented by other treaties, including the Convention on Biological Diversity (CBD), the UN Fish Stocks Agreement (UNFSA), and other developing mechanisms, including the BBNJ Treaty, which is the marine genetic resources (MGRs), the environment impact assessment (EIA) and area-based management tools (ABMTs) such as marine protected areas (MPAs) and capacity building in Favor of fair participation. The 2016 South China Sea Arbitration and ITLOS advisory opinions present judicial developments that broadly interpret UNCLOS by establishing requirements of ecosystem-based management and due diligence, showing that underlying obligations are present, but implementation remains slow because of the sovereignty tensions, technological asymmetries, and lack of incentives to comply with the obligations, etc. The paper relies on empirical evidence in international research, including the IPCC ocean reports and the Kunming-Montreal Framework on ocean protection of 30×30, to assess the current state of development and obstacles.
The main aim is to give some practical recommendations to policymakers illustrating how business-led, treaty-based strategies that are similar to effective biodiversity regimes on the ground can achieve remarkable conservation benefits, especially with BBNJ ratification being driven by the High Ambition Coalition. Organisations and nations implementing systemic approaches to MPAs and sharing of benefits of MGRs are likely to improve ecological sustainability, spur blue economy innovation, and achieve inclusive international governance, reflecting executive team diversity gains that improve productivity. The paper will continue by summarising the structure of the UNCLOS, complementary tools, obstacles, and suggestions of high seas protection in a transformative manner.
LEGAL FRAMEWORK UNDER UNCLOS
The United Nations Convention on the Law of the Sea, or UNCLOS, was adopted back in 1982 and came into effect in 1994. It’s often called the “Constitution for the Oceans” because it lays down the rules for how countries manage the seas, their resources, and the environment. With 169 nations having signed on, it creates a thorough framework for all things maritime. 1In Part XII, which covers Articles 192 through 237, the treaty places a broad duty on states to safeguard and conserve the marine environment, as stated in Article 192. This responsibility has been expanded by courts to include protecting marine biodiversity through an ecosystem-based approach. Article 194(5) strengthens this by requiring countries to take steps to stop, lessen, and manage pollution from any source that could damage living marine resources or marine life. This is especially relevant for biodiversity-rich areas on the high seas, which are at risk from things like ship traffic, plastic debris, and nutrient pollution from runoff.2
International cooperation through Article 197, which calls on states to work together globally or regionally to develop rules for protecting the environment. This includes advancing the conservation of marine biodiversity in areas beyond national jurisdiction, often referred to as ABNJ. 3When it comes to living resources, Part VII of the treaty, which deals with the high seas, requires states under Article 119 to manage and protect targeted fish stocks and related species. This involves applying principles of maximum sustainable yield and reducing unintended catches, or bycatch. Similarly, Article 61 in Part V, covering exclusive economic zones (EEZs), imposes comparable duties on coastal nations.4 The International Tribunal for the Law of the Sea (ITLOS) has provided further insight in its advisory opinions, such as the one from the 2015 Mox Plant case, confirming that these responsibilities include exercising due diligence to address potential impacts on biodiversity from activities like deep-sea mining.5
A. Key Provisions on Biodiversity Protection:
• Article 192: General duty to protect and preserve the marine environment, interpreted broadly to include biological diversity.6
• Article 194: Pollution prevention with ecosystem safeguards; states must ensure activities under their jurisdiction do not harm the high seas.7
• Article 211: Flag state enforcement of international pollution rules, linking to biodiversity via MARPOL integration. These provisions form a patchwork rather than a dedicated biodiversity regime, lacking explicit marine protected areas (MPAs) or genetic resource rules.
B. Judicial Interpretations Expanding Scope:
In the 2016 South China Sea Arbitration case, where the Philippines brought claims against China, the Tribunal determined that China’s construction of artificial islands breached Article 192 of the United Nations Convention on the Law of the Sea by causing damage to coral ecosystems. This ruling underscored the essential role of biodiversity in safeguarding the marine environment. More recently, the International Tribunal for the Law of the Sea’s 20248 Advisory Opinion on climate-related obligations has established that states must undertake due diligence by reducing greenhouse gas emissions to protect ocean health under UNCLOS. Together, these judicial decisions9 promote a shift toward ecosystem-based approaches to marine management. However, persistent shortcomings in sharing benefits derived from marine genetic resources, or MGRs, point to the necessity for additional international agreements to fill these gaps10.
| Provisions | Core Obligation | Biodiversity Link | Judicial Clarification |
|---|---|---|---|
| Article 192 | Protect Marine Environment. | General Biodiversity duty. | South China Sea (Ecosystem)11. |
| Article 194(5) | Prevent harm to marine life. | Pollution- biodiversity nexus. | Mox plant ( due diligence)12. |
| Article 119 | Conserve living resources. | Fisheries & Bycatch | ITLOS climate opinion.13 |
COMPLEMENTARY INSTRUMENTS AND TREATIES
While UNCLOS provides the foundational framework for ocean governance, complementary treaties and agreements address specific gaps in marine biodiversity protection, particularly in areas beyond national jurisdiction (ABNJ). The Convention on Biological Diversity, adopted in 1992 and ratified by 196 parties, applies to marine environments through its objectives of conservation, sustainable use, and fair benefit-sharing from genetic resources, influencing global targets like the Aichi Biodiversity Targets and the Kunming-Montreal Global Biodiversity Framework, aiming for 30% ocean protection by 2030. The CBD’s Jakarta Mandate on Marine and Coastal Biological Diversity promotes ecosystem approaches, complementing UNCLOS Article 197 by fostering regional cooperation on marine protected areas (MPAs)14.
The Agreement for the Implementation of the Provisions of the United Nations Convention on the Law of the Sea of 10 December 1982 relating to the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks, commonly known as the UNFSA and adopted in 1995, puts into practice the requirements of UNCLOS Articles 61 through 73 and Article 119. It does so by emphasising principles such as precaution, ensuring that conservation measures are compatible across jurisdictions, and adopting an ecosystem-based approach to fisheries management. 15Regional Fisheries Management Organisations, or RFMOs, operating under the UNFSA, like the Indian Ocean Tuna Commission, carry out stock assessments and work to minimise bycatch. Nevertheless, these efforts are often hindered by illegal, unreported, and unregulated fishing, which poses significant threats to marine biodiversity.16
1. The BBNJ Agreement: A Landmark Complement
Adopted on June 19, 2023, as the third implementing agreement under the United Nations Convention on the Law of the Sea, the Agreement under UNCLOS on the Conservation and Sustainable Use of Marine Biological Diversity of Areas Beyond National Jurisdiction, commonly referred to as the BBNJ Treaty, directly addresses gaps in the governance of the high seas. It is structured around four key pillars: the management of marine genetic resources, including benefit-sharing through a global fund; area-based management tools such as marine protected areas; environmental impact assessments; and capacity-building, along with technology transfer. 17Opened for signature on September 20, 2023, the treaty will enter into force once 60 countries have ratified it. The High Ambition Coalition is actively promoting swift ratification to ensure alignment with the Kunming-Montreal Global Biodiversity Framework targets.18
• Marine Genetic Resources and Benefit-Sharing: This pillar regulates access to genetic resources from the deep sea, requiring that both monetary and non-monetary benefits be shared with developing nations—a provision notably absent from the original UNCLOS text.19
• Marine Protected Areas and Area-Based Management Tools: It facilitates the establishment of representative networks of protected areas in areas beyond national jurisdiction, drawing on guidance from the Convention on Biological Diversity20.
• Environmental Impact Assessments: The agreement mandates assessments for activities that could cause significant harm, thereby strengthening the due diligence obligations outlined in UNCLOS.21
Other instruments include the Convention on Migratory Species (CMS, 1979), protecting transboundary marine species, and the London Convention/London Protocol (1972/1996) on seabed dumping, which integrates with UNCLOS Part XII pollution duties.22 The Paris Agreement (2015) indirectly supports ocean-based climate mitigation, recognising biodiversity’s role in carbon sinks23.
2. Synergies and Institutional Mechanisms:
These various treaties work together through shared mechanisms such as clearing-house platforms, Conferences of the Parties (COPs), and interfaces between science and policy. For example, the COP for the BBNJ Agreement is designed to align with the outcomes of the CBD’s COP-15. 24However, challenges arise from overlapping responsibilities and the fact that not all countries are parties to every treaty, which calls for harmonisation under the compatibility clauses in UNCLOS Article 311. Additionally, there is judicial synergy, as evident in opinions from the International Tribunal for the Law of the Sea, which draw on principles from the Convention on Biological Diversity to interpret UNCLOS provisions.25
| Treaty/Agreement | Key Focus | UNCLOS Complement | Status (2025) |
|---|---|---|---|
| CBD (1992) | Genetic Resources, MPAs | Article 197 corporation | 196 parties. |
| UNFSA (1995) | Fish Stocks | Article 61,119 fisheries | 91 parties |
| BBNJ (2023) | MGRs, EIAs, ABMTs | High Seas Biodiversity | 10+ ratifications |
CHALLENGES AND GAPS IN INTERNATIONAL LAW
Despite the strong legal frameworks established by the United Nations Convention on the Law of the Sea and its related treaties, major obstacles continue to hinder the protection of marine biodiversity, especially in areas beyond national jurisdiction. In these regions, fragmented governance allows threats such as overfishing, deep-sea mining, and climate-driven ocean acidification to spread without adequate control. Enforcement primarily depends on flag state jurisdiction, as outlined in UNCLOS Articles 92 and 94, which unfortunately encourages the use of “flags of convenience” that often ignore violations. The lack of a centralised authority worsens these compliance issues, as seen in the ongoing problem of illegal, unreported, and unregulated fishing, which has depleted about 33% of global fish stocks. 26While judicial developments, like the South China Sea Arbitration, have reinforced obligations to protect ecosystems, they carry no binding weight without the consent of the states involved, underscoring the tensions between national sovereignty and the freedoms of the high seas under Article 87.27
Implementation hurdles compound these issues: developing states often struggle with limited capacity for monitoring and conducting environmental impact assessments, and the technology transfer provisions in the BBNJ Agreement remain untested until the treaty is ratified. Additionally, sectoral overlaps between Regional Fisheries Management Organisations and emerging marine protected areas can lead to disputes over jurisdictional authority. 28The United Nations Convention on the Law of the Sea’s emphasis on pollution in Part XII falls short in addressing non-point sources such as microplastics and underwater noise, and it lacks detailed provisions on marine genetic resources, resulting in inequities in bioprospecting where benefits tend to favour technologically advanced nations. Integration of climate change considerations is still in its early stages, even though the International Tribunal for the Law of the Sea’s 2024 advisory opinion connects greenhouse gas emissions to the due diligence requirements under Article 194.29 Unfortunately, adaptive measures are not keeping pace with the Intergovernmental Panel on Climate Change’s projections, which foresee a 20-30% loss of marine biodiversity by 2050.30
1. Key Gaps and Their Implications
• Regulatory Fragmentation: Sectoral treaties, such as the UNFSA for fisheries, often fail to adopt integrated approaches to ecosystem management, in stark contrast to the successes achieved on land through the Convention on Biological Diversity.31
• Compliance and Enforcement: The reliance on flag state jurisdiction allows for evasion of responsibilities, while the opt-out provisions for marine protected areas in the BBNJ
Agreement weaken the overall binding nature of these measures.32
• Equity Deficits: Before the BBNJ Agreement, there was no mandatory requirement for sharing benefits from marine genetic resources, which has marginalised the contributions of countries in the Global South.
Geographical and substantive voids further heighten these risks: Areas beyond national jurisdiction encompass 64% of the world’s oceans, yet they currently have less than 1% designated as comprehensive marine protected areas, leaving them exposed to emerging threats like seabed mining under the oversight of the International Seabed Authority. In this context, exploratory contracts are advancing faster than environmental safeguards.33 Moreover, public awareness and the inclusion of stakeholders remain limited, which impedes effective transboundary cooperation.34
| Gaps | Manifestation | Consequences | Potential BBJN Mitigation |
|---|---|---|---|
| Enforcement | Flag state reliance | IUU fishing persistence | Compliance Committee |
| MGR Access | Unregulated bioprospecting | Inequitable benefits | Global Fund |
| Climate Integration | Weak Article 194 links | Acidification threats | EIAs for GHG activities |
| MPAs | No ABNJ networks | Habitat loss | Representative systems |
These gaps highlight the urgent need for more ambitious and coordinated efforts: although the BBNJ Agreement offers promising solutions, its effectiveness hinges on achieving 60 ratifications, with only around 10 or more secured as of 2025, and fostering synergy with Regional Fisheries Management Organisations. This will require robust science-policy interfaces and incentives to encourage widespread participation. 35Failing to tackle these issues could allow international law to perpetuate a tragedy of the commons across the vast blue frontier of the oceans.
CONCLUSION
International law, rooted in the United Nations Convention on the Law of the Sea and strengthened by complementary agreements such as the Convention on Biological Diversity, the UNFSA, and the groundbreaking BBNJ Agreement, creates a comprehensive yet incomplete framework for protecting marine biodiversity amid growing human-induced pressures. Our analysis shows that UNCLOS’s fundamental duties under Articles 192, 194, and 197, reinforced by judicial rulings in cases like the South China Sea Arbitration and advisory opinions from the International Tribunal for the Law of the Sea, require ecosystem-focused safeguards and diligent efforts, marking significant strides in managing pollution and conserving fisheries. Nevertheless, ongoing shortcomings in enforcing rules on the high seas, ensuring fair sharing of benefits from marine genetic resources, and developing cohesive responses to climate change reveal the drawbacks of disjointed sectoral strategies, where reliance on flag state authority and clashes over sovereignty continue to accelerate the loss of biodiversity at concerning speeds.
Empirical evidence indicates that nations implementing structured, treaty-driven approaches, much like corporate diversity programs that deliver leadership benefits, can achieve notable conservation gains, especially through the BBNJ Agreement’s elements of marine protected areas, environmental impact assessments, and capacity-building. These are set to help meet the Kunming-Montreal Framework’s goal of protecting 30% of oceans by 2030, once 60 ratifications are reached. Groups such as the High Ambition Coalition demonstrate proactive leadership by aligning Regional Fisheries Management Organisations with new tools to promote equitable governance, fairly distribute the advantages of the blue economy, boost ecological strength, foster innovation from genetic materials, and support worldwide food security. Still, achieving this will require broad participation, strong links between science and policy, and measures to address resource limitations in developing countries, turning the freedoms of the high seas into a model of collective responsibility.
Research should focus on tracking compliance, evaluating the BBNJ Agreement’s impact after it entered into force, and developing flexible plans for challenges like deep-sea mining and climate tipping points, ensuring that international law shifts from vague commitments to enforceable standards. Effective application not only prevents the tragedy of the commons but also enriches humanity with varied oceanic insights for lasting well-being, similar to how diverse workplaces enhance productivity. Policymakers are called upon to ratify and put these frameworks into practice, preserving the oceans as the vital blue core of our planet’s health.
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Footnotes
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2. The International Legal Framework for the Protection and Sustainable Use of Marine Biological Diversity, Centre for International Law, https://cil.nus.edu.sg/publication/international-legal-framework-protection-sustainable-use-marine-biological-diversity/ (last visited Mar. 21, 2026).
3. Article 197 of Indian Constitution, Testbook, https://testbook.com/constitutional-articles/article-197-of-indian-constitution (last visited Mar. 21, 2026).
4. The Marine Insurance Act, 1963
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7. Id.
8. Cases | PCA-CPA, https://pca-cpa.org/cases/ (last visited Mar. 21, 2026).
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11. https://www.state.gov/wp-content/uploads/2022/01/LIS150-SCS.pdf
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14. https://www.cbd.int/doc/ref/mar-jm-booklet.pdf
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