Efforts to restore the oceans are gaining momentum

Two years ago, the United Nations General Assembly concluded a historic treaty,¹ the High Seas Treaty,² an agreement to protect and preserve the biodiversity of the ‘high seas’ for future sustainable use. The term ‘high seas’ refers to oceans and seas outside territorial waters.

If the treaty is properly implemented, it will play a key role in halting the loss of biodiversity in the ocean and addressing the effects of climate change on the ocean.

It has been agreed that steps can only be taken once at least 60 countries have ratified the treaty. Unfortunately, ratification is progressing slowly. Europe was quick to ratify as a gesture, as did the State of Palestine (not a member of the UN), but because Europe is an economic organisation, this remained a gesture and does not count towards the minimum of 60. On 19 September 2025, Morocco became the 60th country to sign, making the treaty valid!³ As of 11 January 2026, 81 countries have ratified the treaty,⁴ but unfortunately the Netherlands is still not among them. Please note: we are not there yet, because it has also been agreed that the treaty will only become legally binding 120 days after the 60th signature. This means that the actual protection of the open ocean can start on 17 January 2026.

This protection includes the designation of marine protected areas (MPAs) for 30% of the ‘open ocean’. This protection applies to biodiversity throughout the water column, from the surface to the seabed. By 2030, 30% of the ocean will no longer be accessible for mining, unsustainable fishing and other disruptive activities.

Sustainable use

Activities for sustainable use are permitted provided they are appropriate and comply with the rules of the agreement. This means, among other things, that indigenous peoples can continue to fish. Marine scientific research may also be carried out, with a fair distribution of the resulting findings. Fair and equitable sharing of research and the benefits of protection is part of the treaty because knowledge, the necessary technology and research facilities are not available in all countries. That is why benefit sharing is an integral part of the treaty.

If the ocean is left undisturbed, hunting is banned or reduced, only sustainable fishing is permitted, water quality is monitored and structures are restored (such as oyster beds), the potential for ecosystem recovery is enormous.⁵ However, this potential for recovery is highly dependent on a number of factors, one of the most important being depth. The deep-sea floor needs a much longer recovery time. Mining activities destroy marine and seabed life, and it is highly questionable whether this can ever recover.^{6 7}

Literature on slow recovery:

1. https://sdgs.un.org/documents/ares72249-international-legally-binding-instr-23175 ↩︎
2. https://highseasalliance.org/treaty-negotiations ↩︎
3. https://nos.nl/artikel/2583241-verdrag-dat-oceanen-moet-beschermen-kan-na-jaren-onderhandelen-in-werking-treden ↩︎
4. https://highseasalliance.org/treaty-ratification/map ↩︎
5. Duarte, C.M., Agusti, S., Barbier, E. et al. Rebuilding marine life. Nature 580, 39–51 (2020). https://doi.org/10.1038/s41586-020-2146-7 https://eprints.whiterose.ac.uk/id/eprint/159093/ ↩︎
6. https://deep-sea-conservation.org/wp-content/uploads/2024/01/DSCC_FactSheet2_DSM_science_4pp_OCT_23.pdf ↩︎
7. Jones, D.O.B., Arias, M.B., Van Audenhaege, L. et al. Long-term impact and biological recovery in a deep-sea mining track. Nature 642, 112–118 (2025). https://doi.org/10.1038/s41586-025-08921-3 ↩︎