Trips Analysis of Swimming Crab Gillnets Based on Vessel Monitoring System

Abstract

Gill net is an important traditional fishing net, which has the largest number in China. It is accounting for one third of the total vessel number. More than 60000 Chinese fishing vessels were equipped with Beidou terminals. They are similar to the VMS (Vessel monitoring system) system in the world. It can send information of time, speed, course and position of fishing boat. Its time and space resolution are high. The trajectories of fishing vessels are curved lines, and port area is plane. There is a spatial relationship between them. In this paper, the relationship between trajectories of fishing vessels and port surface is used to extract 15000 voyages of 56 fishing vessels. 16.91% of them had a voyage within one day. The fishing vessels with long trips come from Shengsi, Taizhou, Sanmen and Linhai. The trips of fishing vessel were concentrated in Shengsi, accounting for 84% of the total, and Taizhou accounted for 5.4%. The other port only had 10 to 40 vessel trips.