Fishing at the High Seas: the Global Network Connecting Ports to Fishing Areas

Trabajo presentado en la Conference on Complex Systems (CCS), celebrada en Lyon del 25 al 29 de octubre de 2021.Human activities and natural resources are coupled through biological, economical, political and social aspects. In particular, fishing is a complex activity due to the interaction of multiple factors. For example, there is an interplay between the specific interests of extracting industries and those of nations, having the right to regulate fishing within their Exclusive Economic Zones (EEZs). The problem of sustainable fishing becomes harder at the Areas Beyond National Jurisdiction (high seas), where the fishing stocks are shared resources and the regulation is weaker. We analyse one year of fishing vessels’ trajectories, obtained from the Automatic Identification System (AIS), to understand how fishing is distributed at the high seas. We find an accumulation of fishing effort at the external borders of the most productive EEZs, hindering the sustainable fishing within those waters, such that 47% of the fishing effort in the high seas concentrates in a 200 km strip adjacent to the EEZ borders. To quantify this observation, we obtain 14 marine provinces from the trajectories of the vessels and link these provinces to the ports that give support to the vessels fishing on them. This leads to a global network where typically the ports are specialized on one or two provinces, and those located in low and middle-income countries have a key role, becoming potential candidates to receive rewards for control and catch verification tasks