Fishing, shipping, bioprospecting, and other activities continue to expand, turning the high seas — a space "open to all yet difficult to govern collectively" — into a grey zone of ocean governance. The international community has responded by adopting the Agreement on the Conservation and Sustainable Use of Marine Biological Diversity of Areas Beyond National Jurisdiction (BBNJ) through the United Nations, in an effort to establish a framework for protecting and managing the high seas.
The high seas will be bound by the treaty, supporting the conservation of biodiversity and sustainable management beyond national jurisdiction. Image credit: wanzi989813/Pixabay
The High Seas: The World's Largest and Most Difficult-to-Govern Ocean Zone
The high seas cover roughly two-thirds of the global ocean and account for ninety percent of the total volume of Earth's habitable space. Falling outside the jurisdiction of any nation, they harbour an extraordinary range of life — from phytoplankton to blue whales. The high seas sustain global fisheries, food security, and access to marine genetic resources, yet without a binding international treaty, governance has remained fragmented and piecemeal, with marine protected areas covering just one percent of this vast expanse.
What Is BBNJ, and What Does It Cover?
After nearly twenty years of negotiations, the United Nations announced in September 2025 that 60 countries had ratified BBNJ, with the treaty formally entering into force on 17 January 2026. Participating nations are now legally bound to act together in addressing climate change, biodiversity loss, and pollution.
The treaty encompasses four key themes:
1. Area-Based Management Tools
Establishing marine protected areas on the high seas, using defined boundaries and legal measures to protect biodiversity and ecological integrity.
2. Marine Genetic Resources
Sharing the benefits derived from the commercial use of marine genetic resources found in the high seas — including applications in pharmaceuticals, cosmetics, food, and biotechnology.
3. Capacity Building and Technology Transfer
Supporting lower-income countries in building the capacity to participate in high-seas governance, advancing marine conservation and sustainable management.
4. Environmental Impact Assessments
Establishing standardised assessment procedures, with particular focus on high-risk activities such as marine carbon removal.
The Treaty in Practice: Who's In, Who's Watching?
As of March 2026, 86 countries have ratified the treaty, including China, Japan, France, and Brazil. China alone exports marine products — spanning shipbuilding, aquaculture, fisheries, and offshore oil and gas — worth US$155 billion.
The United States, India, and Russia have yet to ratify. The US has signed but not ratified (marine product exports: US$61 billion); India has signed but not ratified (US$19 billion); Russia has indicated a preference for maintaining existing governance frameworks.
Under the treaty, the first Conference of the Parties (COP1) must be convened within one year of entry into force to establish governance structures and discuss financial mechanisms.
With the treaty in place, there is renewed hope for stronger protection of deep-sea biodiversity. Image credit: NOAA/Unsplash
From Fragmented Management to Integrated Governance
The high seas are currently governed through a patchwork of bodies: Regional Fisheries Management Organizations (RFMOs) oversee fisheries, while the International Seabed Authority (ISA) regulates deep-sea mining. BBNJ will operate alongside these institutions in an overlapping and cooperative manner — fisheries will be held to environmental standards, and an ecosystem-based approach to ocean resource management will be adopted, bringing human activities under more comprehensive and coherent regulation.
BBNJ represents an international milestone for the protection and sustainable sharing of ocean resources. It marks a shift for the high seas from open-access competition toward collective governance and equitable benefit-sharing, making marine conservation a shared global responsibility.
References
- Harvard University, Background information on Ocean Governance and the BBNJ Treaty
- UN News, Game-changing international ocean treaty comes into force
- World Resources Institute, After 20 Years, an Agreement to Safeguard the 'High Seas' Takes Force
※ This article is reprinted from the Delta Electronics Foundation's Low-Carbon Life Blog: 〈公海條約生效！BBNJ如何終結「無人管理」的海洋時代〉, co-produced with BlueTrend.
