International waters, known as the high seas, span more than 60% of the world’s ocean and are home to diverse ecosystems, deep-sea habitats, and migratory corridors for iconic species. The riches of these waters also support economies and communities worldwide. As part of the global ocean system, the high seas support the ocean’s role in stabilizing the climate. Overall, the ocean absorbs roughly 30% of human‑generated CO₂ emissions and more than 90% of excess heat.
With the ratification of the High Seas Treaty, countries now have a pathway to establish connected, representative, and global Marine Protected Areas (MPAs) in international waters. This new governance framework can help protect marine biodiversity, strengthen ecosystem resilience, and support the more than 3 billion people whose lives and livelihoods depend on a healthy ocean.
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Dive deeper into how TNC is helping to establish the first generation of high seas MPAs.
Learn MoreTNC is working closely with governments and partners to help establish the first generation of high seas MPAs by 2030.
Leveraging science-driven design, strong regional and global partnerships, innovative financing and policy leadership, TNC is currently focused on three crucial high-seas areas: the Walvis Ridge, the Salas y Gómez and Nazca Ridges, and Micronesia. In the future, we aim to expand our work to further sites. Collectively, this work has the opportunity to contribute up to 200 million hectares of ocean protection, an area larger than Indonesia.
This vast underwater mountain range extending from Namibia’s continental shelf into international waters serves as vital oceanic feeding grounds for migratory species. A highly productive upwelling system, it is globally significant for biodiversity and livelihoods across Namibia, Angola, and South Africa.
Along the western coast of South America and directly adjacent to the Humboldt Current, the most productive upwelling marine ecosystem on the planet, the Salas y Gómez and Nazca Ridges provide critical habitats and migration corridors for at least 80 threatened or endangered species. The ridges are also closely linked to the social, economic, and political importance of many fisheries, particularly the Humboldt squid fishery and Chilean jack mackerel.
To deliver on commitments established in 2006 through the Micronesia Challenge, the island nations and territories of Micronesia are leading one of the clearest near-term opportunities to align ocean governance with long-term conservation finance. Effectively managing the high seas areas adjacent to Micronesian sovereign-waters, including establishing new high seas MPAs, will be essential for maintaining healthy, resilient ecosystems that support biodiversity, climate stability, and sustainable economic development. The areas under consideration include high-biodiversity hotspots that are critically important for marine biodiversity.
The Path Forward
The scale and complexity of protecting the high seas demands collaboration across sectors, geographies and institutions. Working together allows us to align efforts, share knowledge and mobilize the resources needed to address high-priority opportunities in key regions.
As a member of the High Seas Alliance, TNC is driving international policy engagement at the United Nations, coordinating with partners already in place for specific MPAs, and ensuring that our efforts are complementary and grounded in local and regional realities. We are also working to support finance, monitoring, data sharing and capacity-building efforts—critical components for ensuring the High Seas Treaty delivers on its promise of long-term ocean stewardship.
By working together—across borders and sectors, on coastlines and open waters—The Nature Conservancy finds ways to support marine conservation where people and nature thrive for generations.
