Analysis of the activities of high sea fishing vessels from China, Japan, and Korea via AIS data mining

In addition to offshore fishing, high sea fishing has become another important supply channel for seafood. The pelagic catches of China, Japan, and Korea (CJK) account for 60% of the global total, and an analysis of their activities adds essential clarity regarding global fishery resources. This paper develops a framework for analyzing the activities of HSF vessels based on satellite AIS data from 2019, which is used to study the spatial-temporal characteristics of the lengths, speeds, trajectories, and trajectory densities of HSF vessels, the numbers of active vessels, and their average fishing times. The analysis results show that: 1) Chinese HSF vessels are mostly small, relative to Japanese and Korean ships; 2) The speed of Japanese HSF vessels is consistently the highest; 3) All HSF vessels mainly fish in the Northwest Pacific, Western Central Pacific, Eastern Central Pacific, Southeast Pacific, Eastern Central Atlantic, Southeast Atlantic, and Western Indian Oceans; 4) The trajectory distribution of Chinese and Japanese vessels are similar, and both are more widely distributed than Korean vessels; 5) Chinese and Korean HSF vessels mostly enter the Atlantic through the Drake Passage, while Japanese ships mostly enter through the Panama Canal; 6) Chinese HSF vessels fish in Antarctic fisheries all year, while Korean ships aim to fish in Antarctic fisheries in the Spring, Summer, and Winter; 7) China has the largest number of HSF vessels in all fisheries, but their average fishing time is the shortest; 8) The average fishing time of all HSF vessels in Spring and Summer is short, increases during the Autumn, and continues to rise in some fisheries during Winter. This study is not only of great significance for the management and conservation of marine resources, but is also a valuable reference for the promotion of international cooperation in safeguarding marine fisheries.