High Seas Treaty takes effect, creating protections for international waters

The world’s first legally binding treaty to protect marine life in international waters took effect Saturday, setting a framework for marine protected areas on the high seas.

The High Seas Treaty governs vast ocean areas beyond any country’s control and is designed to address threats that include destructive fishing practices, shipping impacts, plastic pollution and overfishing, as well as potential deep sea mining and climate change. The ocean’s role in absorbing carbon dioxide and producing oxygen makes its health central to efforts to address the climate crisis.

The treaty entered into force 120 days after it reached a ratification threshold of 60 countries in September. By Friday, 83 countries had ratified the agreement, including recent additions of China and Japan.

Under the treaty, protected areas will be established through the first global framework aimed at creating Marine Protected Areas on the high seas. While the high seas are about two-thirds of the world’s ocean, only around 1% of those international waters are currently protected.

From Saturday, ratifying countries are required to begin working together on ocean science and technology and to help developing nations build capacity to participate in ocean governance. Companies planning activities that could harm marine life must conduct environmental impact assessments that meet the treaty’s standards, and researchers investigating ocean organisms that could be used commercially must notify other countries and share their findings.

The treaty also requires countries to promote its conservation goals in other international bodies that regulate ocean activities, including regional fisheries organizations, the International Maritime Organization and the International Seabed Authority. With key institutions including the treaty’s secretariat and scientific body still being developed, countries can still begin preparing proposals for Marine Protected Areas immediately. Potential sites cited include the Emperor Seamounts in the North Pacific, the Sargasso Sea in the Atlantic, and the Salas y Gomez and Nazca Ridges off South America.

Conservationists said governments need to move quickly to reach a goal of protecting 30% of the world’s oceans by 2030, which scientists say is critical for ocean health. The speed of that implementation now depends on how strongly protected areas are designed and enforced once proposed sites progress.

Megan Randles, global political lead for Greenpeace’s Ocean Campaign, said the protection offered by the treaty will depend on governments’ willingness to act. She said: “The marine protected areas under the treaty will only be as strong as the governments make them,” and added, “We can’t trust big fishing industry players to simply stop fishing in these critical ecosystems. We need governments to use the treaty to force their hands.”

How protected areas will be monitored and enforced remains undecided, with countries exploring options ranging from satellite technology to coordinated patrols among multiple nations, and from working with other UN agencies to coordinating oversight through additional mechanisms. Rebecca Hubbard, director of the High Seas Alliance, said those details will be worked out as the first protected areas take shape.

Within a year, the treaty’s first Conference of Parties is expected to meet to decide operational details including budgets and committee membership. Countries have already been working through some of those questions at preparatory meetings, with a final session scheduled for late March. The earliest Marine Protected Areas could win approval would be at the second COP, because the scientific body that will review proposals has not yet been established.

The United States signed the treaty but has not ratified it, meaning it can participate as an observer without voting rights. Under international law, signatories are expected to comply with treaty objectives even before ratification, and Hubbard said the U.S. absence does not diminish the agreement’s momentum.

Hubbard said: “The High Seas Treaty has such incredibly broad and strong political support from across all regions of the world,” and she added, “Whilst it’s disappointing that the U.S. hasn’t yet ratified, it doesn’t undermine its momentum and the support that it has already.” Randles also framed the treaty’s impact as a test of political will to translate support into rapid implementation, saying: “The treaty is a sign that in a divided world, protecting nature and protecting our global commons can still triumph over political rivalries,” and concluding, “The ocean connects us all.”