The new High Seas Treaty—the first global legal framework to protect marine biodiversity in international waters—targets the vast ocean areas beyond any nation’s jurisdiction, which cover nearly two-thirds of the ocean and almost half of Earth’s surface. These waters face escalating threats from overfishing, climate change, and emerging industries such as deep-sea mining. “The high seas are the world’s largest crime scene,” said Johan Bergenas of WWF, underscoring longstanding gaps in oversight.
The pact enables countries to designate marine protected areas (MPAs) on the high seas, set rules for potentially destructive activities (including deep-sea mining and geoengineering), and build mechanisms for technology sharing, financing, and scientific collaboration. Decisions will be taken multilaterally via Conferences of the Parties (COPs) rather than by unilateral action. Once the treaty is ratified by the required number of countries, a 120-day clock starts before it enters into force; COP1 must then convene within one year to nail down implementation, funding, and monitoring. Only states that ratify before COP1 will have voting rights there.
Despite strong momentum, the treaty’s punch remains uncertain: the United States and China have signed but not ratified, while Russia and Japan are participating in preparatory talks without joining. Experts warn that staying outside could blunt the treaty’s reach on the very actors with the greatest footprint on the high seas.
Advocates say the agreement plugs a critical governance hole. The high seas absorb heat and CO₂, generate about half the oxygen we breathe, and host migratory species that knit together ecosystems across borders. “These waters belong to no one—and to all of us,” said Lisa Speer of NRDC, noting that failures offshore reverberate in national waters. Still, enforcement will largely rely on flag states regulating their own ships and companies, making broad ratification and robust national implementation essential to meet the global 30×30 conservation target by 2030.
