The transboundary nature of the world\u2019s exploited marine species

Juliano Palacios-Abrantes,William W L Cheung,Gabriel Reygondeau,Colette C C Wabnitz

doi:10.1038/s41598-020-74644-2

Abstract

Regulatory boundaries and species distributions often do not align. This is especially the case for marine species crossing multiple Exclusive Economic Zones (EEZs). Such movements represent a challenge for fisheries management, as policies tend to focus at the national level, yet international collaborations are needed to maximize long-term ecological, social and economic benefits of shared marine species. Here, we combined species distributions and the spatial delineation of EEZs at the global level to identify the number of commercially exploited marine species that are shared between neighboring nations. We found that 67% of the species analyzed are transboundary (n = 633). Between 2005 and 2014, fisheries targeting these species within global-EEZs caught on average 48 million tonnes per year, equivalent to an average of USD 77 billion in annual fishing revenue. For select countries, over 90% of their catch and economic benefits were attributable to a few shared resources. Our analysis suggests that catches from transboundary species are declining more than those from non-transboundary species. Our study has direct implications for managing fisheries targeting transboundary species, highlighting the need for strengthened effective and equitable international cooperation.

Highlights

Regulatory boundaries and species distributions often do not align
Between 2005 and 2014, national fleets targeting these transboundary species within Exclusive Economic Zones (EEZs) caught an annual average of 48.5 million tonnes, representing 82.3% of EEZ-derived catches reconstructed by the Sea Around Us at the species level (Fig. 1a)
Our findings are considerably higher than the previous estimates of 34.2 million tonnes in catches and USD 40,187 million in fishing revenue from shared s tocks[15].When we re-estimated transboundary species’ catches using data consistent with those used in previous studies (FAO global reported data in year 2006), the 633 transboundary species identified here accounted for 40.4 million tonnes of annual catches (i.e., 18% higher than previously estimated)

Summary

Introduction

Regulatory boundaries and species distributions often do not align This is especially the case for marine species crossing multiple Exclusive Economic Zones (EEZs). We combined species distributions and the spatial delineation of EEZs at the global level to identify the number of commercially exploited marine species that are shared between neighboring nations. Forty years after the formal adoption of U NCLOS6 and the subsequent 1995 United Nations Fish Stock Agreement for the cooperation on the management and conservation of straddling and highly migratory resources[13], accurate estimates of the number of exploited marine species shared by neighboring nations are still unavailable. We aim to estimate the number of exploited marine species shared by neighboring countries and determine their contribution to global and regional catches as well as fisheries revenue. We hypothesize that the methodological constraints of previous studies resulted in an underestimation of the number of transboundary species and their contribution to global catch and revenue

Objectives

Methods

Results

Conclusion