Marine Protected Areas Beyond National Jurisdiction: A Legal Study of the BBNJ Agreement’s Potential to Harmonise a Fragmented Ocean Governance Without Undermining Existing Bodies

Abstract

The Agreement under the United Nations Convention on the Law of the Sea on the Conservation and Sustainable Use of Marine Biological Diversity of Areas beyond National Jurisdiction (BBNJ Agreement) introduces an overarching framework for the protection of marine biodiversity in areas beyond national jurisdiction (ABNJs). Central to its operationalisation are marine protected areas (MPAs), which aim to achieve long-term conservation of marine biodiversity by regulating human activities. However, the Agreement enters into a fragmented ocean governance landscape that is characterised by numerous sectoral and regional actors with overlapping competences. This study examines the BBNJ Agreement’s potential to harmonise ocean governance within MPAs, with a specific focus on its obligation not to undermine existing instruments, frameworks and bodies (IFBs). The study develops a contextual interpretation of the ‘non-undermining’ obligation and applies it to three case studies: the International Maritime Organization (IMO), the International Seabed Authority (ISA) and the Western and Central Pacific Fisheries Commission (WCPFC). The obligation is not an absolute prohibition on the BBNJ regime adopting measures where its mandates overlap with another body. Instead, it should be understood to prohibit measures that systematically erode the authority of existing institutions over time by explicitly targeting activities that fall within their core mandates. The findings show that interactions between the BBNJ regime and existing bodies vary significantly depending on institutional mandates and core interests. While its interaction with the IMO and the WCPFC present potentials for constructive coordination and mutual reinforcement, the interaction with the ISA poses further challenges due to its prioritisation of the mining interest and the security of tenure for contractors. However, this deadlock may be challenged by an emerging normative shift in international law, where the obligation to prevent irreversible harm to the environment may redefine how to manage the common heritage of humankind. The study concludes that BBNJ Agreement’s potential to harmonise ocean governance ultimately depends on a flexible and context-based application of the non-undermining obligation and on the willingness of the international community to prioritise long-term biodiversity conservation over sectoral extractive interests.