High Seas, Higher Stakes: Why Vulnerable Marine Ecosystems Matter

Beyond the Borders

Nearly two-thirds of the ocean exist beyond any country's Exclusive Economic Zone (EEZ). These areas are known as the high seas, beginning at the 200-nautical-mile limit of national jurisdiction. This region supports marine life, fisheries livelihoods, and ecosystems passing through national boundaries. At its core, what happens in the high seas influences the health of the general ocean. 

Yet for the same reasons, because the high seas fall beyond any single nation’s jurisdiction, regulations have historically been limited and fragmented. Many areas remain difficult to monitor and, as a result, largely unprotected. In numerous parts of the high seas, we also still know surprisingly little about what lies beneath the surface.  

The Living Treasures of the Deep

Far beneath the waves are delicate ecosystems that have developed over decades, even centuries. Deep sea corals create complex habitats for marine life. Seafloor sponges filter columns of seawater. Seamounts can become epicenters of biodiversity, supporting life at both macro and microscopic scales. These habitats are known as Vulnerable Marine Ecosystems, or VMEs.   

The UN Food and Agriculture Organization formalized the term in 2009, following growing evidence of the effects deep-sea fishing could have on these sensitive seafloor habitats. VMEs like benthic coral reefs, hydrothermal vents, and sponge fields are often structurally complex. They are also slow-growing and may take decades or longer to recover when damaged. These ecosystems serve as habitats and sources of food for a wide range of marine organisms, including crucial fisheries species. As a result, their ecological importance and its fragility make VMEs a focal point of ocean governance debates today.  

For years, the management of VMEs on the high seas has largely depended on Regional Fisheries Management Organizations, each with its own geographic area and mandate. That changed when the High Seas Treaty, or formally known as the Agreement on Biodiversity Beyond National Jurisdiction (BBNJ), marks a historic shift. For the first time, the international community has a global legal framework for protecting biodiversity in waters beyond national jurisdiction, including a pathway for establishing marine protected areas across the high seas. But any effort to manage these ecosystems depends on good science. We need to know where they are, what lives there and how they function. 

That is where expeditions can make a difference. 

Exploring Roo Rise

In July 2026, OceanX led a 22-day expedition to Roo Rise alongside the Minderoo Foundation, Minderoo OceanOmics Centre at The University of Western Australia, the Western Australian Museum, the Living High Seas Initiative, and Nanyang Technological University. 

Roo Rise sits in international waters south of Java, near Christmas Island in the eastern Indian Ocean. It is a region where many basic scientific questions remain unanswered. Its chain of seamounts has only been lightly mapped, and little is known about the coral, sponge and other benthic communities that may live there.  

Aboard the OceanXplorer, the team used a range of technologies to build a clearer picture of the area. Seafloor mapping helped reveal the shape and structure of the seamounts. Environmental DNA, or eDNA, sampling allowed scientists to detect genetic traces of organisms in the environment. Researchers also searched for features associated with VMEs, including coral structures, sponge gardens and concentrations of marine life.  Using these tools together gives scientists a more complete view of Roo Rise, from the physical structure of the seafloor to the species living around it. 

The region is also significant for life far beyond the seafloor. To date, these waters contain the only known spawning ground of the critically endangered Southern Bluefin Tuna, connecting Roo Rise to ecological systems across the global ocean. 

This expedition will help scientists better understand the biodiversity of this little-studied part of the Indian Ocean and assess whether areas of Roo Rise meet the criteria for Vulnerable Marine Ecosystems. 

The seafloor mapping data can also contribute to global efforts such as Seabed 2030 and the General Bathymetric Chart of the Oceans (GEBCO), adding to the international effort to build a more complete map of the ocean floor. 

From Exploration to Protection

Roo Rise reflects a central part of OceanX’s approach: exploration helps build the knowledge needed to understand and protect the ocean. 

By studying where Vulnerable Marine Ecosystems occur, what species they support and how they function, scientists can provide the evidence needed to guide future management of the high seas. That evidence is especially important for VMEs, which can be slow to recover and difficult to protect across international waters. 

OceanX works with research institutions and scientific partners to ensure that expedition data contributes to a wider body of knowledge. The more we learn about ecosystems like those at Roo Rise, the better equipped the international community will be to make informed decisions about their protection.