Written by Nereus Research Fellow Guillermo Ortuño Crespo,

According to a new paper published today in Nature Ecology & Evolution from co-authors Guillermo Ortuño Crespo, Daniel Dunn, Patrick Halpin (Duke University) and others, the current patchwork of global ocean governance is fragmented and leaves thousands of high-seas fish species at risk due to commercial fishing activities. As States at the United Nations (UN) begin to negotiate a new treaty to strengthen the legal regime for marine biodiversity in areas beyond national jurisdiction (ABNJ – greater than 200 nautical miles from shore), it is vital that discussions include the many high-seas fish species that are “either targeted, affected or simply unstudied and potentially at risk of slipping through the cracks of current management arrangements”. Involved parties need to “adopt an instrument that establishes or enhances mechanisms to asses impacts of fisheries non-target species” and to apply an ecosystem-based approach that will “avoid or prevent adverse impacts on biodiversity as a whole.”

After almost 20 years since informal discussions for a new treaty to protect biodiversity in the high-seas began at the UN, we are at a stage where the UN General Assembly is meeting in New York City to negotiate the text for a new legally binding treaty under the UN Convention on the Law of the Sea (UNCLOS) – it is an opportunity of a lifetime to increase the sustainability of human activities in 46% of our planet, so we must ‘get it right’.

Early in the negotiating process, involved parties agreed that the new treaty should not ‘undermine’ existing agreements or organizations. While we generally agree that the UN should avoid institutional redundancies where possible, some nations have weaponized that principle to avoid including the impacts of human activities on high seas biodiversity, particularly that of commercial fisheries. This is a position that has gained momentum at the UN negotiations and threatens future conservation and management actions for thousands of fish species in the high seas.

Throughout the study we challenge the notion that all fish biodiversity in the high seas is currently being monitored or managed by contrasting estimates of known fish diversity with a comprehensive database of global fisheries population assessments.

We found that of the 4,018 different species of fish that have been identified in the high seas, only 4.8% of them have a stock assessment or an analogous form of population model. We think these findings make a compelling case that the current “business as usual” institutional structures will likely not be appropriate to meet the broader biodiversity management goals of the high-seas treaty.

We believe that the new treaty could help regional fisheries management organizations (RFMOs) fulfill their conservation and management mandates, and hope that this treaty encourages research, monitoring, and management of all forms of marine biodiversity that are currently not being monitored by existing bodies or treaties.