A new era in the relationship between human societies and the marine worlds has just begun. Or, at least, that is the intention.
This Saturday, January 17, the High Seas Treaty enters into force, or, more formally, the Agreement on the Conservation and Sustainable Use of Marine Biological Diversity in Areas Beyond National Jurisdiction (BBNJ, in English).
Nearly two-thirds of the Global Ocean lie beyond the domain of any state, the so-called “high seas.” In practice, it is a vast expanse of marine waters that are “no-man’s land,” where the force of Law, when it exists, does not prioritize the protection of the diversity of life that inhabits them. A patchwork quilt of regional fishing agreements, covenants related to maritime transport, and a handful of marine protected areas that do not cover 1% of the high seas, which, thus, remains an ungoverned world.
In truth, the high seas are governed by the creatures that live there and crossed by humans who wish to stay out of sight of authorities based on land.
It is estimated that more than 10 million species make the high seas their homes and that many more remain to be discovered in the deepest and most mysterious abysses.
These waters are also the stage for criminal activities, such as piracy, drug and human trafficking, onboard slavery on ships, illegal disposal of chemicals or other types of waste, and fishing outside the parameters defined by the rules that govern the activity.
To bring order to a vast portion of the Global Ocean subjected to all kinds of pressures, and, above all, to safeguard the great biodiversity of life that inhabits it and the important services these ecosystems provide (such as carbon sequestration, for example), the countries of the world adopted the High Seas Treaty in 2023.
After two years open for signatures by United Nations member states, and nearly 20 years of negotiations, the agreement finally reached the minimum of 60 ratifications in September 2025 and has now surpassed 80. The text provides that 120 days after this threshold is reached the agreement enters into force, and that happens today, January 17, 2025.
What to Expect from the New High Seas Treaty
There seems to be a consensus that the High Seas Treaty represents a historic milestone in protecting and governing the ocean beyond national jurisdictions, but also there, because what happens in one part of the ocean affects, in one way or another, all the others.
Moreover, as this is an agreement that creates a binding international legal framework to regulate and thus protect the “waters of nobody,” treating them as a global common good that must be conserved and whose use must be sustainable, thinking about the proper functioning of these ecosystems and for future human generations.
In practice, the treaty will allow the creation of marine protected areas in international waters, imposes the obligation to carry out environmental impact assessments for activities that unfold in these oceanic regions and could seriously harm biodiversity, and creates rules for all countries to share, fairly and equitably, the financial and non-financial benefits of the commercial use of genetic material harvested from marine organisms in the high seas, such as bacteria, corals and sponges.
Furthermore, mechanisms are foreseen to promote international sharing of technology and knowledge, especially with the poorer countries so that they can be more active participants in the conservation and sustainable management of the seas and to ensure that they participate fully in implementing the treaty.
Despite what is written in the text of the agreement, it is well known that between aspirations and realization, between rhetoric and practice, there is an entire ocean in between. The entry into force of the treaty is merely the beginning of what will be, if History serves as an example, a long and turbulent process.
And, already, several critical areas can be foreseen for the High Seas Treaty to fulfill the aims it sets out.
Noting that the agreement is “fundamental” to achieving the global target of protecting at least 30% of marine and terrestrial areas by the end of the decade, as reflected in the Kunming-Montreal Biodiversity Framework, Catarina Grilo, Director of Conservation and Policy at WWF Portugal, tells us that success “will depend heavily” on the tools that countries now have at their disposal.
“Experience shows that real protection at sea often falls short of political commitments,” she states, so the environmental organization views the entry into force of the High Seas Treaty with “realistic optimism.” In other words, it recognizes that we are entering “a new era of possibilities for ocean protection,” but understands that “the real test will be ensuring that protected areas are well designed to be truly effective, well managed and not just symbolic decisions.”
From the Nature Conservation League side, Teresa Fonseca, technical coordinator of the Coastal Zones and Ocean Program, stresses that the treaty’s effectiveness largely depends on how it will be “implemented, financed and monitored,” requiring “a serious political commitment and robust compliance mechanisms that still need to be defined in practice.”
The technical also says that it is necessary for ratifications to continue, because the treaty only binds legally the countries that join it, and its impact will be all the more significant the more states ratify and adhere to its rules.
In this line, Patrícia Nogueira, environmental policy manager of the Association for Marine Environment Research, highlights that “the absence of ratification by major powers, such as the United States and Russia, could prove problematic in the implementation of measures.”
For the technician, the true realization of the High Seas Treaty will only be possible “with global participation and with broad international cooperation.”
Sérgio Carvalho, Deputy Director for International Affairs of the Blue Ocean Foundation, also believes that “political will, cooperation and implementation” are essential for the protections outlined in the treaty to be effectively realized. Therefore, he says expectations should be “ambitious, but realistic.”
“This is a structural shift toward better governance of the global ocean, whose success will depend on the determination with which states act in the coming years,” he states, adding that “the Treaty fundamentally changes the rules of the game by moving from fragmented oversight to coordinated management.”
The fact that deep-sea ecosystems are so distant from the coast may also pose serious challenges to the supervision of the protections’ implementation. Joana Soares, projects and policy coordinator for the Ocean program at Zero, tells us that “protecting an ecosystem beyond borders, such as the high seas, is very challenging and requires a strong hand from the competent authorities, as well as good sense and cooperation among countries.”
Although, historically, “the translation of policies into real and lasting protection” has been “a chronic governance problem” for marine ecosystems, Joana Soares assures that there is a “growing number of allies who are following these processes” and who will be attentive to potential failures in implementation so they can be “signalised and corrected more quickly.”
At a time of great political polarization around the world and geopolitical tensions among major powers, the High Seas Treaty will very likely have to navigate through uncertain and rough waters, but perhaps states can put aside their differences for the global common good that is the Ocean, whose health is indispensable to life on Earth.
How About Deep-Sea Mining?
Deep-sea mining is an area of the ocean that typically begins at 200 meters below the surface, when sunlight starts to struggle to penetrate the water, creating a world of growing darkness.
Despite the austere conditions, with high pressures and freezing temperatures, the deep sea is full of life, with animals whose forms and lifestyles challenge the imagination, which has evolved a delicate balance that makes it very sensitive to disturbances. However, it is also in the seabed that some of the largest deposits of minerals, such as nickel, copper, aluminum and lithium, are found, highly sought after for the production of technologies such as smartphones, wind turbines, solar panels and batteries. Thus, these minerals are described as fundamental to the transition from fossil-fuel-dependent economies to economies anchored in energy considered ‘clean’.
However, and although it is not yet legally possible in international waters, deep-sea mining, as scientists say, can strongly disturb and even destroy entire habitats, through direct impacts of mineral extraction machines and also through the creation of dust clouds that make waters turbid, releasing pollutants long sequestered in untouched sediments and burying creatures beneath layers of sea dust.
It is estimated that the deep sea covers something like two-thirds of the global seabed area, so a large part of these habitats are in international waters.
A still image shows a cloud of sediments trailing a mining robot in the Clarion-Clipperton Zone, Pacific Ocean.
Photo: BGR
Although the regulation of deep-sea mining remains the responsibility of the International Seabed Authority (ISA), the High Seas Treaty may come to act to protect these habitats from potentially destructive activities, especially due to the environmental impact assessment mechanisms it defines.
Catarina Grilo, from WWF Portugal, explains that deep-sea mining risks the objectives and “the vision” of the High Seas Treaty, which has “a fundamental role” in creating “a space of global cooperation to face risks that cross borders,” such as those inherent to mining.
“It is important to emphasize that the treaty does not solve the underlying problem of mining, which is that we do not know enough about deep-sea ecosystems to set safe limits,” she notes, so “we continue to advocate the precautionary principle and not proceed with this activity.”
Until now, 40 countries have publicly come out against deep-sea mining in international waters, which Catarina Grilo sees as reinforcing “the need for prudence and coordinated action.”
Stating that the High Seas Treaty does not categorically ban mining nor by itself ensure firm protection against this activity, Teresa Fonseca, from the Nature Protection League, says that what happens is that the process to allow mining will be “more transparent, scientifically grounded and subject to collective decision-making.”
The technician believes this could function as a “brake” on mining “depending on global political will,” and calls for the primacy of the precautionary principle, meaning that activities whose impacts on ecosystems cannot yet be accurately assessed should not be allowed. In other words, when in doubt, it is better to prevent than to remedy.
“The remote nature of the seafloor, the weak legal reach and the extraction pressures will make it difficult to ensure the treaty’s full compliance. We must stay vigilant,” cautions.
Sérgio Carvalho, from the Blue Ocean Foundation, also believes that the fact that the High Seas Treaty raises “the level of demand in how human activities in the global ocean are assessed” contributes to “a more cautious, ecosystem-based approach” that will also apply to deep-sea mining.
Photo: Thomas Kelley / Unsplash.
But for the Ocean to be properly protected, it is necessary, says the Deputy Director for International Affairs, that there be cooperation and coordination between the treaty regime and the ISA mandate.
In light of the legal framework created by the High Seas Treaty, and even though recognizing that this instrument does not prohibit deep-sea mining “explicitly,” Joana Soares, from Zero, says that “it becomes particularly difficult to justify advancing mining activities.”
Because, as she explains, “with the currently available scientific evidence, it is not possible to demonstrate that these do not cause significant harm to marine ecosystems.” The Zero technician asserts that deep-sea mining is “incompatible with the objectives of marine biodiversity conservation and with a truly sustainable use of the ocean.”
As such, she considers that the treaty can function as a “brake on impulses,” especially when some countries, such as the United States of America, “have expressed positions that do not favor high-seas protection” and when the race for critical minerals gains momentum as the energy transition advances at a rapid pace.
Another COP
Just like other major multilateral instruments, such as the UN Framework Convention on Climate Change, the Convention on Biological Diversity, the United Nations Convention to Combat Desertification and the Convention on Migratory Species, the High Seas Treaty will also have its own Conference of the Parties (COP).
COPs are the main decision-making bodies of the conventions, where the signatory States assess the implementation of the agreements and decide on new paths to strengthen compliance with the aims defined.
In a text published on its online portal, the European Commission says it is in discussions to prepare the first COP of the High Seas Treaty, which will take place one year after the agreement enters into force. Therefore, with no concrete date defined yet, the COP is expected to take place in early 2027.
These international summits, especially at the environmental level, such as climate and biodiversity, have been marked by some progress, but also by a lot of frustration and promises yet to be fulfilled. Will this COP follow the same path?
Experts appear more optimistic about this COP of the High Seas Treaty, at least regarding its effectiveness, precisely because, unlike other conventions, it will be based on a binding legal treaty that must now be translated into concrete on-the-ground actions, or, more precisely, in the ocean.
Of course, that does not mean that the High Seas COPs will be meetings free of turbulence and interference and economic and political interests that prefer to derail negotiations on positive measures that fulfill the real purpose of the treaty. However, the decisions that come out of them, at least that is the expectation, will not be mere symbolic statements or rhetorical exercises, as they will be based on a legally binding agreement and not solely on the goodwill of states parties.
Still, the success or failure of the High Seas Treaty will depend exclusively on the willingness of the countries that are part of it and also on the public pressure that will be exerted on them to keep their word.
