After two decades of discussion and five years of negotiations, an international conference reached agreement in March 2023 on a new United Nations’ treaty—a legally binding multilateral instrument focused on the conservation and sustainable use of areas of marine biodiversity beyond national jurisdiction (BBNJ). The BBNJ region covers 64 percent of the ocean’s surface area and 95 percent of its volume; however, only 1 percent of it is protected today.
The new treaty is underpinned by the United Nations Convention on the Law of the Sea (UNCLOS), which defines coastal state jurisdiction and establishes the international high seas. Nothing in the new treaty prejudices the sovereign rights and jurisdictions of coastal states or the fundamental freedom of navigation principles set forth in UNCLOS. The High Seas Treaty does highlight and advance the responsibilities of all states under UNCLOS to protect and preserve the marine environment.
The treaty’s primary objective is to establish a legal framework in which marine protected areas (MPAs) within the high seas can be proposed, assessed, and managed (if approved). A Conference of the Parties (COP) has been created as an international body to decide whether to establish new MPAs with appropriate management plans. COP decisions (by consensus or adopted by a two-thirds majority of the parties present and voting) will be based in part on the assessment of a scientific and technical body, the robustness of an environmental impact assessment, and inclusive, transparent consultations with an array of stakeholders, including indigenous peoples, adjacent coastal states, and relevant global, regional, and sectoral bodies.
The agreement makes clear the COP must consult and coordinate with existing sectoral bodies for shipping (the International Maritime Organization under the UN), future seabed mining (the International Seabed Authority created by UNCLOS), and fisheries (a host of regional and subregional management bodies); other bodies addressing ocean issues such as the International Hydrographic Organization and the World Meteorological Organization also would have technical relevance for the MPA decision-making process. Future plausible ocean uses such as geoengineering to mitigate climate change and high seas aquaculture also would likely be addressed by the COP under the treaty’s objective to ensure conservation and sustainable use of marine biological diversity.
The treaty also addresses marine genetic resources (MGRs); capacity-building and transfer of marine technology (focused on developing states); and environmental impact assessments (EIAs). MGRs are addressed to ensure equitable sharing of benefits with developing nations, geographically disadvantaged states, and indigenous peoples. Higher EIA standards and guidelines, and obligations by treaty parties are outlined in detail.
While the treaty’s text was formally adopted by the UN in June 2023, several upcoming challenges constrain full implementation. Ratification by 60 UN member nations is required. A suite of complex international structures must be established: the COP, a scientific and technical body, and committees on finance, implementation and compliance, access and benefit sharing, and capacity-building and transfer of marine technology. A functioning treaty secretariat is required soon to provide administrative support to the COP and the developing network of committees, and to establish key connections to existing sectoral and regional authorities. Mobilizing and involving the international marine scientific community also will be important in the MPA nomination and evaluation processes.
The High Seas Treaty is a landmark governance regime for protecting the global ocean. Establishing potential MPAs in such high seas regions as the Arabian Sea, Gulf of Guinea, Emperor Seamount Chain (northwest of Hawaii), and Sargasso Sea will improve the long-term health and survivability of the ocean. The treaty also provides a formal process for reaching a conservation goal of protecting 30 percent of the world’s ocean, lands, and freshwater by 2030.
