High Seas Treaty

December 14, 2025

The United Nations High Seas Treaty is scheduled to come into force in January 2026, marking a landmark moment in global ocean governance.

Designed to strengthen the protection of marine biodiversity in areas beyond national jurisdiction, the treaty aims to regulate human activity across nearly two-thirds of the world’s oceans.

While the agreement has been widely welcomed as a breakthrough for conservation, a new global review suggests that its success may hinge on a critical and unresolved challenge: whether the organisations currently responsible for managing highseas fisheries are prepared to adapt to this new legal and environmental framework.

High-seas fisheries are primarily governed by Regional Fisheries Management Organisations (RFMOs), bodies tasked with regulating fishing activity across vast international waters. For decades, these organisations have focused largely on maintaining fish stocks at commercially viable levels, often prioritising catch limits and quotas over broader ecosystem health.

The High Seas Treaty, however, demands a far more holistic approach. It introduces tools such as marine protected areas in international waters, mandatory environmental impact assessments, and stronger accountability mechanisms — all of which require fisheries governance to extend beyond single-species management.

The global review highlights significant gaps in the current system. Many RFMOs operate with limited mandates that do not explicitly include biodiversity conservation. Decision-making within these bodies is often slow, consensus-driven, and heavily influenced by major fishing nations, making it difficult to adopt precautionary measures.

Enforcement remains weak, with limited capacity to monitor illegal, unreported, and unregulated fishing across vast ocean spaces. Data gaps further complicate matters, as scientific information on deep-sea ecosystems and migratory species remains incomplete.

The treaty’s entry into force will require RFMOs to align their rules with new international obligations. This includes cooperating with conservation bodies, sharing data more transparently, and integrating ecosystem-based management into fisheries regulation.

The review warns that without substantial reforms, existing institutions may struggle to implement these changes effectively, risking a disconnect between treaty ambitions and on-the-water realities.

At the same time, the treaty presents an opportunity. It offers a legal framework to modernise fisheries governance, strengthen scientific collaboration, and rebalance power toward sustainability.

If RFMOs can evolve from narrowly focused management bodies into stewards of ocean ecosystems, they could become key allies in protecting biodiversity beyond national borders.