Published: March 10, 2023 By

After two weeks of negotiations, delegates of the United Nations reached a historic agreement this week to protect marine biodiversity in international waters. This treaty would place portions of the world’s oceans, known as the “high seas,” into protected areas and allocate more money for marine conservation.

Due to highly fragmented governance, until now there has not been a coherent mechanism in place to protect the high seas—yet they harbor incredible marine biodiversity, including deep sea coral reef ecosystems and critically important migratory routes for fish, birds and mammals. 

Emily Nocito, a graduate student in environmental studies who studies international environmental governance and marine conservation, was present at the U.N. meeting in New York City. Mike Gil, assistant professor of ecology and evolutionary biology, is a marine biologist who has studied plastic pollution in the high seas.

Nocito and Gil explain why the high seas matter and why the new treaty will benefit all of us.

Emily Nocito

Emily Nocito, graduate student in environmental studie, was present at the U.N. meeting in New York City. Photo courtsey of Emily Nocito. 

What are the high seas? 

Nocito: The high seas are essentially any ocean waters 200 nautical miles out from a coastline. That first 200 fall under national jurisdiction of whatever country that shoreline belongs to, but once you reach the 200 mark, it is considered the high seas. They are also called international waters, or we sometimes say “areas beyond national jurisdiction.” It is not owned by a single country or even a single continent, it is a global common. And that's why it's fallen to the United Nations to take care of these oceans. 

Why are the high seas important?  

Nocito: The high seas make up two-thirds of our global ocean, about half of our planet. They are important for migratory species, such as whales, sea turtles and sharks and they are home to well over 200,000 marine species. We are also reliant on our global oceans for fisheries, and they help mitigate climate effects. Even though you may never see or experience the high seas, they're still fundamentally important to humans. 

Gil: There are also biodiversity hotspots in the high seas that can support an incredible diversity of marine life. Many marine species are used in the synthesis of pharmaceutical products that help with human ailments, like cancer treatments. But we haven't rigorously explored many of these places, and so it is entirely possible that there are yet to be discovered species in high seas environments that could help humankind with human health issues. 

Who was involved in this landmark agreement? 

Nocito: This agreement is under the U.N. Convention on the Law of the Sea, which is what has been primarily the form of governance in international waters. Countries of the U.N. were present, as they are the ones that will be eventually hopefully adopting and ratifying the agreement. But there were also research institutions, nongovernmental organizations and U.N. bodies. 

Mike Gil

Mike Gil, assistant professor of ecology and evolutionary biology, is a marine biologist who has studied plastic pollution in the high seas. Photo courtesy of Mike Gil. 

Why is this treaty a big deal? 

Gil: It's taken two decades of negotiation to get to this point. It’s a game-changer: It sets up the necessary infrastructure for protections to be made on specific areas of the high seas environments, likely in the form of what we call marine reserves, similar to national parks on land. This allows us to protect and preserve these ecosystems in a state that is as close to their natural state as we can manage. 

Nocito: This is the first piece of ocean governance at the international level we've had in decades. So to be there at this pivotal, history-setting moment is not just wickedly cool, but also gives a lot of faith to diplomacy. This should provide a beacon of hope for not just our oceans, but other things that we are trying to protect in our environment. It can be done. 

How will the treaty protect our oceans? 

Nocito: Marine protected areas are a management tool within a geographic boundary where you can have more regulations of human use. So maybe no fishing or limited fishing, maybe no mining, or no shipping routes through certain areas, which can protect key ecosystems.

Gil: What marine reserves can do is alleviate human driven pressures that harm ecosystems. Species like sharks, sea turtles, and dolphins use high seas environments for migration and as important food sources—and then they also contribute to the food webs of coastal systems like coral reefs and seagrass meadows. If those organisms are better protected, they're more likely to continue to be able to play an important role in near-shore environments, and support the resilience of those coastal environments that humans also heavily depend upon.

How will this treaty benefit all of us? 

Gil: The high seas make up 60% of our oceans, which contribute an estimated $1.5 trillion annually to the global economy. If fisheries industries that are dependent on high seas environments collapse, that will have economic ramifications globally. In addition, between 3 and 3.5 billion people in the world depend on seafood as a primary food source—that's something like 40% of the global population. It’s also true that we harvest genetic resources from marine organisms that are used to create pharmaceuticals. So if you don't care about anything else, this treaty helps ensure the ability of humankind to utilize nature to support human life. 

What happens next? 

Nocito: First and foremost, the treaty needs to be adopted and ratified. Then you need to create a conference of parties, a science and technical body, and then the real work can start to begin. Who is going to enforce it, how much is it going to cost? All of those are still fundamental questions that this conference of parties is going to have to sort out. But we're celebrating this huge win. It is the beginning of a new chapter.