Monitoring global fishing activity in proximity to seamounts using automatic identification systems

Abstract

Seamounts are prominent features of the seafloor that are often located in Areas Beyond National Jurisdiction (ABNJs). Whilst comprehensive biological information is lacking on most of these features, they have been recognised for hosting high biodiversity across multiple trophic levels. Technological advancements have enabled greater exploitation of biological resources further offshore with increasing concern over the long-term impacts of anthropogenic activities on vulnerable distant and deep-sea habitats. Analysis of ex situ vessel tracking technologies such as Automatic Identification Systems (AIS) have enabled spatial patterns of fishing activity to be monitored over large geographical areas. In this study, analysis of fishing activity within 30 km of seamount summits at the global scale found that these features within the waters of the Pacific Island Group and the Mediterranean Sea were subject to the highest levels of longlining and trawling activities respectively. Fishing in proximity to seamounts is dominated by the flag states of Taiwan, China, Japan, South Korea and Spain. Furthermore, our results reveal that the majority of sea areas managed by many Regional Fishery Management Organisations (RFMOs) have experienced increased fishing activity at seamounts compared to areas in the same ocean basin without management. This study demonstrates how free web-accessible data can be used to gain insights into remote areas where in situ research is prohibitively expensive and logistically challenging.