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Why and how G20 leaders should support the UN High Seas Treaty

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Why and how G20 leaders should support the UN High Seas Treaty

Two-thirds of our common ocean lies outside of national jurisdictions. Under 2% of this maritime area, which is also called the high seas, is protected.

The recently agreed UN High Seas Treaty is meant to improve the protection of biodiversity and regulate activities in this vast expanse of ocean that has gone without oversight until now. But the treaty will need backing at many levels in order to be successful.

Elin Leander shares insights on how G20 members and other nations can take a stand supporting the treaty and why it matters.

Elin Leander, Ana Calvo / Published on 8 September 2023

What does the new UN High Seas Treaty mean for members of the G20


All the G20 members have committed to protecting ocean biodiversity, as signatories to another treaty, the Convention of Biological Diversity (CBD). By regulating areas beyond national jurisdiction, the High Seas Treaty can play a pivotal role in achieving the CBD’s 30×30 target of protecting 30% of our oceans by 2030.

We could flip that question: What does the G20 mean for the new UN High Seas Treaty? The new treaty is seen as a major step towards global ocean conservation, yet at least 60 national governments must ratify it to make it legally binding and effectively implemented. The G20 members’ support is essential for ratification and strengthening the treaty and for ramping up ambitions for high environmental standards.

What is new with the UN High Seas Treaty in relation to the protection of our oceans?

This is the first internationally legally binding mechanism to protect biodiversity in the ocean areas beyond national jurisdiction – the BBNJ. Among the changes the Treaty brings are introducing large-scale marine protected areas (MPAs), which will increase the protected area in international waters. Right now a mere 2% of the high seas is protected by MPAs.

The Treaty also will regulate the extraction of marine genetic resources. That’s beyond what people might normally think of as biodiversity – or fish. It covers things as tiny as microorganisms that might be the source of biotechnology solutions for a range of commercial applications.

Under the treaty, there will be both knowledge and financial benefit sharing on all new marine discoveries made within the high seas. In addition, new rules regarding environmental impact assessments for offshore projects such as wind power farms will be detailed at the first Conference of Parties, or COP.

What would be the ideal outcome you would like to see from the G20?

The G20 has an opportunity to drive the successful ratification and implementation of the new High Seas Treaty, as well as shift the framing of other treaties to lead to a more successful global management of the common ocean.

The G20 could use these platforms for dialogue, as opposed to allowing political tensions to spill over to the arena of marine management and protection.

As the High Seas Treaty does not have the mandate to undermine other instruments, collaborations between the different ocean governance instruments will be necessary to ensure effective protection in line with the 30×30 target. The G20 has a significant role to play here. Almost all G20 members are also members of other instruments that have great impact – on the common ocean and on the new treaty.

Why would countries object to protecting Areas beyond national jurisdiction (ABNJ)? And what are the risks of not protecting them?

We can illustrate this with the Convention on the Conservation of Antarctic Marine Living Resources (CCAMLR), for the Southern Ocean. In the convention, where consensus drives decision-making, China and Russia opposed the approval of new suggested MPAs. China has expressed opposition to MPAs because it’s seen as it equals no fishing. They argue this has impacts on food security.

However, governance of MPAs can allow fishing activities during some seasons in the year, or move the location of an MPA together with important species when these migrate, allowing fishing of other species while those protected are away.

MPAs have been suggested by the scientific committee to safeguard ecosystems around Antarctica. The risk I see of not taking action is that all political tensions will play out and there will be an increase in what is known as securitization, the argument that security trumps biodiversity. Ultimately that will hinder the protection of our oceans. And it will destroy the very resources that make countries food secure – marine biodiversity.

As a marine biologist, I know that if you protect the ocean, it can improve the conditions for fish populations to recover, and furthermore increase the chances of food security for everyone in the future.

Elin Leander, SEI Research Fellow in Sustainable Oceans research theme for Mistra Geopolitics

What message would you like to share with the leaders of the G20

As we wrote in our policy brief to the T20, the G20 members should support and push other members to ratify the High Seas Treaty, as well as take leadership for global cooperation and multilateralism, instead of increased geopolitical tension.

Overcoming differences in priorities, policies and resource allocation will facilitate international cooperation, as expressed in the Outcome Document and Chair’s Summary from the G20 Environment and Climate Ministers’ Meeting in Chennai, India. The ministers’ statements after that meeting seem to strongly support multilateral oceans governance, such as “reiterat[ing] our commitment to protect, conserve, restore, and sustainably use coastal and marine ecosystems and their biodiversity” and how they welcome the adoption of the High Seas Treaty and “call on countries for its early entry into force and implementation”. We hope these statements will be echoed at the G20 Leaders’ Summit.

Yet concrete initiatives and tangible progress is what will protect our oceans. One of the gaps the ministers highlighted is sustainable funding mechanisms for protecting, conserving and restoring ocean ecosystems and marine resources. We urge the G20 as global leaders to also commit financially to actions for protecting our seas.

Edited 12 September 2023.

Elin Leander
Elin Leander

Research Fellow

SEI Headquarters

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