We Agreed to Protect the High Seas; Now We Need to Learn How

After nearly 20 years of talks, UN member states have, in a historic move, agreed to the first-ever treaty to protect the high seas. The treaty establishes the process for expanding marine protected areas within the high seas.

Becca Hamilton, Marine Consultant with International Projects Group, a specialist team within the RSK Group, explains how we can ensure that these areas deliver results for marine conservation.

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In terrestrial ecosystems, protecting habitat, more often than not, results in the protection of biodiversity within that habitat. This principle does not translate so easily to the marine environment. In aquatic environments, oil spill events can ride the currents to the furthest reaches of the ocean; many marine species have planktonic stages of life, and marine mammals, turtles, and sharks can travel hundreds or even thousands of kilometers on migrations between feeding and breeding grounds. This scale of mobility means it can be hard to utilize marine protected areas on the high seas effectively outside of protecting static seafloor habitats like deep oyster beds and deep-sea vent systems. How can we make sure this historic treaty is implemented in a way that truly maximizes benefits for the marine environment?

When planning a marine protected area, it is crucial to choose the best location: a threatened area with the potential to support high biodiversity. This is important because there are many areas on the high seas that do not have the conditions to permanently support rich biodiversity; in fact, much of it is deep water far from the shore, so protecting these areas may achieve relatively little. On the other hand, selecting an area of high biodiversity that is not at risk could basically be a box-ticking exercise to meet the goal set out by the treaty of protecting 30% of the high seas by 2030. While there is some value to protecting any area of the ocean, if we are to get the most value from new marine protected areas, they must protect that which otherwise could be lost, balancing the most biodiverse and most vulnerable.

Areas at risk of expanding fishing activities, especially bottom trawling, are good candidates for increased protection, as this fishing practice can destroy up to 95% of the biodiversity of an area. The Southwest Pacific is heavily fished for the orange roughy, which is already on Australia’s list of endangered species owing to overfishing, so a marine protected area here could provide a sanctuary for this species and safeguard its population.

Choosing the right area requires a thorough understanding of the types of habitats and species found in and passing through an area—the baseline conditions—then ensuring that these are species that will benefit from protection. This is a complex exercise that will involve looking at nutrient levels, habitat complexity, ocean currents, and much more. Ultimately, you need to be able to demonstrate how a proposed protected area will allow biodiversity to truly recover.

Choosing feeding or breeding grounds for long-migrating species such as the loggerhead sea turtle and the northern right whale, both endangered species, would safeguard the protection given to these species in territorial coastal waters. Choosing areas of high fish spawning would ensure more animals survive the early life stages, meaning their populations can better support animals further up the food chain, including humans. Protecting areas of high productivity like upwellings and seamounts is another approach, as these features can support biodiversity across trophic levels, like the seasonal plankton blooms that we see in the Southern Ocean that support seabirds, fish, whales, and other species.

It is good news that stakeholder engagement is firmly embodied in the treaty; this ensures that the protected area is not disproportionally benefiting or disadvantaging certain groups of people. Over three billion people across the world rely on the ocean for their protein needs, often in developing countries. In the Philippines, for example, fish constitutes 40% of the diet, so there is a human element that must be considered. At the same time, stakeholder engagement can ensure the protected area is actually enforceable. This will be crucial, as the problem with protecting the high seas is that they are not part of any exclusive economic zone, territorial sea or inland or archipelagic waters, putting them over 200 nautical miles away from land. This distance makes it difficult to enforce compliance within, or even monitor, high seas protected areas. This, along with a lack of ownership by any sovereign state, is why, historically, the high seas have been a no man’s land with illegal fishing and unregistered vessels.

New and advancing technology like high-definition commercial satellite imagery, autonomous aerial and surface vehicles and remote underwater vehicles are excellent tools for enforcing a marine protected area on the high seas, and we can use these to monitor biodiversity over time to check the protections are meeting objectives and actually causing an increase in biodiversity over time.

With that in mind, we need bold action from one of the treaty signatories to submit the first proposal for a marine protection area on the high seas. The greatest danger is that, because it is a challenge and because the high seas are out of sight, there will be reluctance to be the first to act. We can’t afford that delay. The oceans are vital for food security, they act as a carbon sink in the fight against climate change and it is estimated that roughly half of the Earth’s oxygen is produced in the ocean. Everything in the ocean is connected, from the beach to the abyssal plain, so what happens in one area will affect the other. That means all member states have interests in protecting the high seas and in ensuring the success of the marine protected areas that are now possible to be created.

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