High Seas Treaty: A Historic Step to Protect the Ocean Beyond Borders 

Feature image: Diverse benefits of supporting the High Seas (BBNJ) Treaty. Credit: (O’Leary et.al, 2022). The diverse benefits of biodiversity conservation in global ocean areas beyond national jurisdiction. Frontiers in Marine Science. 

The High Seas Treaty, officially known as the Agreement on the Conservation and Sustainable Use of Marine Biological Diversity of Areas Beyond National Jurisdiction (BBNJ Agreement), was adopted by United Nations Member States in June 2023 after nearly two decades of international negotiation. The treaty reached the required threshold of 60 ratifications in September 2025, triggering a 120-day countdown to entry into force. It entered into force on 17 January 2026, making it the first legally binding global framework to protect biodiversity in international waters that lie beyond any one country’s control. The treaty builds on the United Nations Convention on the Law of the Sea and will be governed through an institutional process including a Preparatory Commission and the first Conference of Parties, which will guide full implementation. 

Key Developments at a Glance 

• A global legal framework now exists to conserve biodiversity in high seas waters beyond national jurisdiction 
• Countries can establish Marine Protected Areas in these international waters 
• Environmental impact assessments are required for major activities such as deep sea mining 
• Benefits from marine genetic resources must be shared equitably 
• International cooperation, scientific research, and capacity building are strengthened 

Why the High Seas Treaty Matters for Climate Action? 

The ocean plays a vital role in regulating the climate by absorbing large amounts of heat and carbon dioxide and by sustaining natural systems such as ocean circulation, plankton communities, and marine food webs that influence weather patterns and food chains. Healthy marine ecosystems, including phytoplankton and large marine species, support carbon storage and help regulate temperatures and nutrient cycles. The High Seas Treaty supports climate action by protecting biodiversity in international waters, enabling marine protected areas, and improving oversight of activities that could damage these systems. By safeguarding ocean health, the treaty strengthens climate resilience and supports global food security. Evidence from Frontiers in Marine Science shows that conserving biodiversity in the high seas contributes to both climate mitigation and adaptation. 

Global Benefits of the Treaty 

• Increased protection for carbon-rich ocean ecosystems 
• Strengthened resilience of marine and coastal environments 
• Support for sustainable fisheries and food systems 
• Expanded scientific collaboration and monitoring 
• Shared benefits and capacity building for developing countries 

As implementation of the High Seas Treaty moves forward, continued engagement and cooperation from all countries will be essential. Wider participation through signature, ratification, and effective implementation can help ensure that the treaty delivers meaningful benefits for ocean health, climate resilience, and long-term global sustainability. 

Read more: Extreme weather events | Health risks | Climate Risks Daily 

Original source: https://unu.edu/ehs/article/what-high-seas-treaty-and-why-it-important