An ocean agreement to govern the high seas was struck Friday when Morocco became the 60th nation to sign on.

The high seas treaty is the first legal framework aimed at protecting marine biodiversity in international waters, which account for nearly two-thirds of the ocean and nearly half of Earth’s surface. These areas, which lie beyond the jurisdiction of any single country, are vulnerable to threats including overfishing, climate change and deep-sea mining.

“The high seas are the world’s largest crime scene,” said Johan Bergenas, senior vice president of oceans at the World Wildlife Fund.

Still, the pact’s strength is uncertain as some of the world’s biggest players — the U.S., China, Russia and Japan — have yet to ratify. The U.S. and China have signed, signaling intent to align with the treaty’s objectives without creating legal obligations, while Japan and Russia have been active in preparatory talks.

Ratification triggers a 120-day countdown for the treaty to take effect. But much more work remains to flesh out how it will be implemented, financed and enforced.

Lisa Speer, director of the Natural Resources Defense Council's international oceans program, said the treaty fills a gap for protecting waters that, because they belong to no one, are “the responsibility of all of us and none of us at the same time.” And failing to protect those waters could mean damage for any individual nation's waters, she added.

“Marine life doesn’t respect political boundaries. So fish migrate across the ocean. ... Same with turtles, with seabirds, and a whole host of other marine life,” Speer said. “And so what happens in the high sea can really affect the health and resilience of the ocean within national jurisdiction, within our coastal waters.”

The high seas are home to a vast array of marine life and play a crucial role in regulating Earth’s climate — they absorb heat and carbon dioxide, and generate half the oxygen we breathe. The treaty is also essential to achieving what’s known as the global “30x30” target — an international pledge to protect 30% of the planet’s land and sea by 2030.

The treaty creates a legal process for countries to establish marine protected areas in those waters, including rules for potentially destructive activities like deep-sea mining and geoengineering schemes. It also establishes a framework for technology-sharing, funding mechanisms and scientific collaboration among countries.

Crucially, decisions under the treaty will be made multilaterally through what are known as conferences of parties (COPs) rather than by individual countries acting alone.

Within one year of the treaty taking effect, countries will meet to work out the foundational questions of implementation, financing and oversight at that first COP. Only countries that ratify before COP1 will have voting rights at COP1.

Some experts warn the treaty’s impact could be blunted if the most powerful players on the high seas remain outside it.

The treaty does not create a punitive enforcement body of its own. Instead, it largely relies on individual countries to regulate their own ships and companies.

AP Video produced by Teresa de Miguel

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