High-seas fish biodiversity is slipping through the governance net
States at the United Nations have begun negotiating a new treaty to strengthen the legal regime for marine biodiversity in areas beyond national jurisdiction. Failure to ensure the full scope of fish biodiversity is covered could result in thousands of species continuing to slip through the cracks of a fragmented global ocean governance framework.
Over the past 70 years, commercial fisheries have expanded farther and deeper into the open ocean1,2,3,4, impacting many forms of marine biodiversity that exist in areas beyond national jurisdictions (ABNJ; generally, the area beyond 200 nautical miles from shore)5,6. The growth of other industries, such as shipping, has further expanded the presence of humans in the open ocean, while new activities, such as seabed mining, are on the horizon1. These impacts are compounded by the effects of a changing climate, deoxygenation and ocean acidification7,8,9.
In 2017, after more than a decade of informal discussions at the United Nations (UN) regarding gaps in the legal framework for the conservation and management of marine biodiversity beyond national jurisdiction (known as the BBNJ process), states agreed to convene an intergovernmental conference for the negotiation of an legally binding instrument under the UN Convention on the Law of the Sea (UNCLOS) (an ‘implementing agreement’)10.
The agreement to launch the negotiations was partly achieved by the consensus that any new instrument “should not undermine existing legal instruments and frameworks and relevant global, regional and sectoral bodies”10. This has generally been assumed to mean that the new instrument should complement and strengthen the existing framework and prevent the adoption of weaker or dissonant management measures. However, a small number of states wish to see commercial fisheries (including all forms of fish biodiversity, which they group as a commercial resource whether or not it is harvested) excluded from a new agreement and are concerned that any new provisions will inevitably undermine existing fisheries management bodies. However, there is a significant difference between the number of fish species subject to management and the number of fish species in ABNJ that may be impacted by commercial fishing activities. As fish are a major component of marine biodiversity in ABNJ and have a major role in marine ecosystem functioning, it is important to understand what regional fisheries management organizations (RFMOs) are in fact responsible for monitoring and managing. Here, we contrast fish biodiversity estimates in ABNJ with a comprehensive database of existing fish population assessments to help delineate the current competencies of RFMOs and identify areas of improvement that could be addressed both through the new agreement as well as by strengthening the mandates and actions taken by such bodies.
We first describe the overarching legal framework for high-seas fisheries, then enumerate how many fish species are either targeted, affected or simply unstudied and potentially at risk of slipping through the cracks of the current management arrangements. The final section analyses how these gaps are relevant to ongoing negotiations at the UN for a new treaty and concludes with specific recommendations.