Covering nearly half the surface of our planet, the High Seas is owned by no one, yet belongs to all of us. Plundered by wealthy nations and modern-day pirates, these unprotected waters support a jaw-dropping array of marine creatures and are critical to all life on Earth.

This interactive essay is part of The Great Ocean Commons, a series from Only One underscoring the urgency for world leaders to support an ambitious High Seas Treaty. Scroll to discover how the High Seas sustains wildlife and people all over the globe.

I. The Ultimate Unknown

The open ocean has long been a place of wonder, dynamism, discovery, and strife.

It is also perhaps the ultimate unknown. Most of us will never experience the body of water known as the High Seas outside of history, literature, or the imagination. We catch fragmented glimpses of this great blue expanse only when we view images of the Earth from space, or if we take a transoceanic flight. Yet, despite the apparent distance between our daily lives and the ecosystems of the open ocean, we are in fact all connected to the High Seas in practical and profound ways.

Individual countries govern the ocean within their exclusive economic zones (EEZs), which are generally agreed to extend 200 nautical miles from shore. But the High Seas sits outside of any country’s authority. Unfathomably vast, the High Seas covers 60 percent of the ocean’s surface and comprises 90 percent of the ocean’s total living space.

II. Unparalleled Ocean Life

In a decade-long project started in 2000, scientists found over 6,000 new species in the High Seas. These rich waters provide critical habitat for myriad creatures.

Marine species including whales, sharks, rays, tuna, and seabirds go on epic migratory journeys across large areas of the High Seas to find food and suitable breeding grounds. One such ocean wanderer is the great white shark. Living along the Northern California coast from September to February, great whites then travel en masse 1,500 miles each way to a remote location halfway between Hawaii and Baja California. Here, in what is commonly called the “White Shark Café,” the sharks spend a few weeks “hanging out” and diving the depths of about 1,000 feet every 10 minutes, gorging on light-sensitive animals such as squid, phytoplankton, and small fish.

Deep sea habitats in the open ocean, such as cold-water corals and sponge fields, have sometimes been around for centuries. What they lack in sunlight, they make up for in unusual and wondrous biodiversity: prehistoric sharks, bioluminescent worms, flamboyant sea fans, octopuses with fins like elephant ears, vampire squid that feed on marine snow. And in the greatest migration on Earth, a menagerie of species moves up toward the surface every night in search of food, creating a moving display like clockwork.

III. Sustenance for Humankind

Capturing carbon at the surface and storing it deep below, the High Seas keeps our planet liveable—the atmosphere would contain 50 percent more carbon dioxide than it does now without this process.

Climate regulation is just one of countless ecosystem services gifted to us by the High Seas. We’re discovering potentially life-saving medicines in ancient coral fields and on seamounts and increasing our knowledge of global biodiversity thanks to the High Seas. As part of the global ocean, the open ocean also supports the lives and livelihoods of millions of people, contributing significantly to the ocean’s economic output (valued at $1.5 trillion).

IV. Protection, Not Exploitation

The term “High Seas” can conjure up pictures of olden-day piracy out on the open ocean—of a lawless commons. In this day and age, the reality is not so different.

Like the rest of the ocean, the High Seas is in grave danger. Its health is rapidly deteriorating due to threats caused by humans, including ocean acidification, shipping traffic, noise pollution, plastic and chemical pollution, deep seabed mining, the climate crisis, and, in particular, unsustainable and illegal fishing. Only a handful of wealthy nations has the means to operate in this distant and enormous part of the ocean and exploit its resources with virtually no control. And modern slavery remains rife in the fishing industry, demonstrating that neither humans nor marine species are safe in an unregulated High Seas.

Large numbers of scientists are calling for at least 30 percent of the ocean, including in the High Seas, to be protected from extractive activities like mining and fishing by 2030. Scientific research and projections indicate this is the only way to save the full spectrum of marine species that depend on the High Seas.

Ocean sanctuaries, or marine protected areas (MPAs), are a key tool for protecting habitats, rebuilding biodiversity, ensuring ocean health is restored, and maintaining ecosystem services for people everywhere on the planet. And even if every nation on Earth created MPAs in 30 percent of their territorial waters, it would only be a fraction of what is necessary, as the High Seas would continue to lack meaningful protection.

As things stand, a mere one percent of the High Seas is fully or highly protected.

There is no formal governance or international agreement in place to define a pathway toward establishing and enforcing MPAs. Success stories are few and far between, but they do exist. The very first High Seas MPA was created over the southern shelf of the South Orkney Islands in the Southern Ocean, safeguarding an astonishing 1,200 different species. Think of how many more species we could protect if we secured comprehensive High Seas MPAs, and of the consequent brighter future for all life on Earth.

V. The Path Forward

We need a High Seas Treaty to rebuild ocean life.

World leaders have been in discussion at the United Nations for nearly 20 years on the subject of a treaty to advance comprehensive, meaningful protection of the High Seas. Over the next year, negotiations will reach their critical culmination. It is our chance to help protect marine biodiversity in the High Seas and halt the collapse of the entire ocean.

An ambitious High Seas Treaty would:

• Establish a strong legal process for the creation, effective management, and enforcement of a network of marine reserves in waters outside of countries’ authority

• Include specific measures to ensure that environmental impact assessments are consistent and rigorous

• Prioritize the establishment of a global decision-making body and dispute resolution provisions for the open ocean

Each of our voices is only a drop in the ocean, but together we can form an unstoppable chorus telling world leaders to protect the Great Ocean Commons, for the sake of the ocean, the planet, and all of us.