For the first time, UN members have agreed on a single treaty to protect biodiversity on the high seas – representing a turning point for large parts of the planet where conservation has previously been hampered by a confusing patchwork of laws.
The UN Convention on the Law of the Sea entered into force in 1994, before marine biodiversity was a well-established concept. The treaty agreement concluded two weeks of talks in New York.
An updated framework to protect marine life in the regions beyond national territorial waters, known as the high seas, had been discussed for more than 20 years, but previous efforts to reach agreement had repeatedly stalled. The unified treaty agreement, which covers nearly half the planet’s surface, was reached late Saturday.
“We really only have two great global commons — the atmosphere and the oceans,” said Georgetown marine biologist Rebecca Helm. While the oceans may attract less attention, “protecting this half of the Earth’s surface is absolutely critical to the health of our planet.”
Nichola Clark, an ocean expert at the Pew Charitable Trusts who observed the talks in New York, called the long-awaited treaty text “a once-in-a-generation opportunity to protect the oceans — a big win for biodiversity.”
The treaty will create a new body to manage the conservation of marine life and establish marine protected areas on the high seas. And Clark said it is critical to achieving the United Nations Conference on Biological Diversity’s recent pledge to protect 30% of the planet’s water, as well as its land, for conservation.

Treaty negotiations were initially expected to end on Friday, but stretched throughout the night and well into Saturday. The drafting of the treaty, which at times appeared to be in jeopardy, represents “a historic and overwhelming success for international marine protection,” said Steffi Lemke, Germany’s environment minister.
“For the first time, we get a binding agreement for the high seas, which until now have barely been protected,” Lemke said. “Comprehensive protection of threatened species and habitats is now finally possible on more than 40% of the Earth’s surface.”
From crayfish to cacti: why thousands of species are at risk of extinction in the United States
The treaty also establishes basic rules for carrying out environmental impact assessments for commercial activities in the seas.
“This means that all activities planned for the high seas will have to be reviewed, although not all will go through a full assessment,” said Jessica Battle, an ocean governance expert at the Worldwide Fund for Nature.
Several marine species _ including dolphins, whales, sea turtles and many fish _ make long annual migrations, crossing national borders and open oceans. Efforts to protect them, along with human communities dependent on fishing or tourism related to marine life, have long proved difficult for international governing bodies.
“This treaty will help tie together the various regional treaties to address threats and issues across the species’ range,” Battle said.

That protection also helps coastal biodiversity and economies, said Gladys Martinez de Lemos, executive director of the nonprofit Interamerican Association for Environmental Defense, which focuses on environmental issues across Latin America.
“Governments have taken an important step that strengthens the legal protection of two-thirds of the ocean and with it marine biodiversity and livelihoods for coastal communities,” she said.
The question now is how well the ambitious treaty will be implemented.
Formal adoption remains outstanding, with many conservationists and environmental groups vowing to watch closely.
The high seas have long been subject to exploitation due to commercial fishing and mining, as well as pollution from chemicals and plastics. The new agreement is about “recognizing that the ocean is not a limitless resource, and it requires global cooperation to use the ocean sustainably,” said Rutgers University biologist Malin Pinsky.
Associated Press writer Frank Jordans contributed to this report from Berlin.
© 2023 The Canadian Press