Brazil Ratifies High Seas Treaty On Ocean Biodiversity

By Fabiola Sinimbu

The Agreement on the Conservation and Sustainable Use of Marine Biological Diversity in Areas Beyond National Jurisdiction – or BBNJ – came into force in January 2026, after two decades of international negotiations. Immediately after the text was finalized in March 2023, 145 countries signed the document that came to be known as the High Seas Treaty, including Brazil.

To come into effect, the accord needed ratification by at least 60 countries to become valid 120 days later. In Brazil, Congress approved the pact on December 16, 2025, but even before that, in September, 60 other countries had already confirmed their adherence.

As of the publication of this story, 84 countries had ratified the agreement, according to the global network of social organizations High Seas Alliance. But why does this international treaty on a common good outside the territories of countries arouse so much interest?

Ana Paula Prates, director of the Department of Ocean and Coastal Management at Brazil’s Ministry of the Environment and Climate Change, says that although other international treaties establish rules for marine biodiversity conservation, they mainly cover national territories, while this is the first to comprehensively address international waters, which represent two-thirds of the planet’s oceans.

“This integrated approach was necessary because everything that happens in international waters also affects our jurisdictional waters – whether it’s biopiracy, the environmental impacts of enterprises such as deep-sea trawling, or even plastic,” she pointed out.

Living beings

With a total area of over 360 million km² and depths exceeding 10 km, the oceans play a key role in balancing the planet’s temperature. They produce more than half of the oxygen necessary for life and are home to a vast biodiversity. Approximately 64 percent of this enormous expanse comprises the high seas, beyond national jurisdictions.

“By getting to know it better and conducting environmental impact studies of human activities in this area, we have the possibility of improving the protection and conservation of this biodiversity, which is by far the most important for the maintenance of life on earth,” says Andrei Polejack, director of research and innovation at the National Institute for Oceanic Research (INPO), a social organization dedicated to ocean research and development.

The text of the High Seas Treaty deals with guidelines and global governance for the conservation and sustainable use of biodiversity in the high seas. It is based on four pillars:

• the creation of marine protected areas in international waters;
• assessment of economic activities in terms of environmental impact;
• the sharing of benefits from genetic resources; and
• technology transfer and capacity building.

In practice, any activity carried out on the high seas will be subject to the rules of the agreement, as the treaty is binding, thus becoming a legal obligation imposed on participating countries. “It will not be up to each country, each company, or their respective countries [to decide]. For example, deep-sea trawling – which is something that happens too often and no one knows where – will now have to be assessed jointly with these countries [that have joined the treaty],” Ana Paula Prates states.

To operate in these regions, the nations will also need to better understand the biodiversity on the high seas, through investments in science and technology such as deep-sea submersibles and genetic mapping of the fauna and the flora there.

Benefits

“We have a wonderful opportunity to find new resources for medicines, cosmetics, and other solutions. But this will have to be evaluated jointly, and the benefits will have to be shared among all ratifying countries. Similarly, another controversial issue that will have to be negotiated is the establishment of marine protected areas,” the representative of the Brazilian Ministry of the Environment said.

The idea is that when there is doubt about the capacity to conserve and maintain the balance of a given ecosystem and the species in it, the region should be protected, with measures ranging from assessing the impacts of human activities to be carried out in the area to the creation of marine protected areas.

“This is a process that adopts some principles of international law, which are binding in this treaty – like the precautionary approach, which states that if we do not know exactly what the impact will be, then it is better to suspend activities,” Polejack noted.

High Seas COP

With the treaty now in force, only countries that have ratified it will be able to participate in the establishment of the institutions, operational rules, and processes necessary for the agreement to become operational. The first talks for the creation of these instruments are expected to take place at the Conferences of the Parties (COP) to the High Seas Treaty.

Even before this stage, when the agreement was signed by the countries interested in participating, the United Nations General Assembly (UNGA) set up a preparatory commission tasked with choosing a country to host the secretariat and other institutions – such as the scientific and technical body – as well as establishing the financial structure and rules for decision-making.

Two meetings were held in April and August 2025, and a third is scheduled to take place in March 2026 at the United Nations headquarters in New York. “At this [meeting], we will be able to decide where the secretariat will be located – which is already under dispute. Belgium has come forward, as have Chile and now China. All three are candidates. We should also set the date for the first COP,” Ana Paula Prates said.

Advantages

Still according to Polejack’s assessment, Brazil has much to contribute with all the diplomatic and scientific knowledge developed in other international treaties – such as those created at ECO92 in Rio de Janeiro, which deal with climate, biodiversity, and desertification. He also considers it important to hold debates on the social and collective interests of the people.

“This work must be based on scientific evidence and must consider the balance between the uses of this biodiversity in areas beyond national jurisdiction, on the high seas, but it must also distribute the benefits generated. So, there’s a huge number of details. It’s a complex agreement, and it really needs all voices together,” he concluded.