The sea, the great unifier, is man’s only hope … and we are all in the same boat.” So said Jacques Cousteau, the French explorer, oceanographer and pioneering film-maker, who notably pivoted from merely sharing his underwater world to sounding the alarm over its destruction.
Half a century later, David Attenborough, a year shy of his 100th birthday, followed Cousteau’s trajectory. In thenaturalist’s acclaimed new film, Ocean, which highlights the destructive fishing practice of bottom trawling, he says he has come to the realisation that the “most important place on Earth is not on land but at sea”.
This message, backed by undeniable indicators of poor ocean health, has boosted calls for more ocean governance and protection. The mood at this week’s UN ocean summit in Nice, which ended on Friday, was that if ever there was a defining “moment” for the ocean, it was happening here, in France’s Côte d’Azur.
But there was also a sense of this sentiment being shared in the wider world, where, partly thanks to the summit, many are finally waking up the reality of the serious decline of something thatmakes up more than 70% of the Earth’s surface.
By the end of the first day, on the roof of the conference centre overlooking the Mediterranean,Emmanuel Macron, the French president and co-host, declared the summit a success. “Never before have so many heads of state and governments met to discuss the seas,” he said, citing the figure of 60 world leaders, three times as many as attended the second UN ocean conference in Lisbon in 2022. About 190 ministers were also in Nice. The US did not attend.
But what, with the eyes of the watching world, was actually achieved for the future health of oceans?
The most important accomplishment was that enough countries either ratified orformally committedto ratifyingthe high seas treaty. Once ratified, this agreement will help achieve an agreed global target of protecting 30% of the world’s seas by 2030. It will provide the first legal mechanism for the creation of protected areas in the high seas, international waters that cover almost two-thirds of the ocean.
The treaty is expected to now come into force by 1 January 2026, said Macron. This alone is an achievement: the early stages of the high seas treaty took 20 years of negotiations before agreement was reached in 2023. Now it could be months away from becoming a reality.
António Guterres, the UN secretary general, called the pace of progress “a record”. “I see a momentum and an enthusiasm that was difficult to find in the past,” he said.
The summit does not carry the weight ofa climate Cop, the annual UN climate change conference where governments and other stakeholders gather to discuss and negotiate on climate action,nor is it legally binding. But it has come at a critical moment for threats facing the seas.
In April, Donald Trump made a move tofast-track deep-sea mining under US law,sidestepping international efforts to regulate the industry. The conference saw four new countries – now 37 – joining France in calling for a moratorium, pause or ban ondeep-sea mining, amid warnings of “irreversible” damage to ecosystems should it go ahead.
Trump’s actions, which were criticised by China, which also wants to mine, have had the effect of “strengthening people’s commitment to multilateralism” and building alliances at a key moment, says John Hocevar, oceans campaign director at Greenpeace USA. “In July, the International Seabed Authority meets to discuss, hopefully, a moratorium on deep-sea mining.”
More than 90 ministers issued a symbolic statement in Nice reaffirming their support for thestrongest possible plastics treaty, to be negotiated when talks resume in August.
Rémy Rioux, a former French negotiator on climate finance at the 2015 Paris agreement, and director general of ADF, France’s development bank, says that Macron has adopted similar diplomacy at the ocean summit that made Cop21 a success.
“There was significant numbers of heads of state in the room, which represents something,” Rioux says. “I’m proud that France has provided a voice to those who are not heard.”
But, in terms of finance, we “are still way behind what the UN say is needed”.
Pacific nations, who contribute least and stand to suffer most from the effects of the climate crisis, sea level rise and ocean pollution, welcomed the chance to talk to Macron. But they were quick to remind larger, more polluting nations that they needed to do more.
Moetai Brotherson, the president of French Polynesia, announced the creation of thelargest protected marine area in the world. It will cover 5m sq kilometres, the nation’s entire exclusive economic zone and will restrict destructive activities such as bottom trawling and deep-sea mining. A fifth will be designated a highly or fully protected area, where only traditional Tahitian boats, ecotourism and scientific exploration is allowed.
“By doing what we are doing, it will putpressure on other countries, including France, to do more,” he says. “Turning this area into a marine protected area is one thing. Ensuring that laws are not broken is another. The responsibility of big nations is not to come and lecture us, but to help us.”
Ralph Regenvanu, Vanuatu’s environment minister, says: “The Pacific island states have banned bottom trawling in their national jurisdictions – and so we are calling on all nations to do the same. The EU is full ofcountries that are still doing this.”
At the start of the conference,the French president found himself under firefor failing to ban bottom trawling in protected marine areas. France announced that instead it would “limit” the practice and seek to protect 4% of its metropolitan waters.
One of the strongest critics of France’s role in the summit, was the granddaughter of Jacques Cousteau. France “over-compromised and under-delivered”, she says.
“This was the moment for France to lead – and they missed it,” says Alexandra Cousteau, also an adviser to international oceans organisation, Oceana. “President Macron promised action on bottom trawling in marine protected areas but delivered only artificial limits and empty words. That’s not leadership – that’s evasion.”
Despite its achievements, the summit highlighted how much is yet to be done. A study by National Geographic Pristine Seas and Dynamic Planet found, for example, that in order to meet the global target of 30x30,85 new marine protected areaswould need to be created daily. So far,less than 3%of the ocean is given this extra protection.
Yet, overall the mood was high, boosted by a surge of enthusiasm for protecting the world’s seas.
“I hate to say it out loud, but it has been better than I expected,” says Hocevar. “The ocean is having a moment and this was the best opportunity to demonstrate momentum.”