Spatial analysis of fishing intensity for Illex argentinus based on fishing vessel tracks

In order to understand the spatial behavior of Illex argentinus fishing vessels, we had analyzed the Automatic Identification System (AIS) data from January to May, 2018. Based on data mining method, we identified the trajectories of squid fishing vessels, and drew the fishing intensity distribution map of squid fishing ground. Then we analyzed the spatial distribution characteristics of monthly fishing intensity of I. argentinus fishing ground. The results show that: 1) The velocity distribution of the squid jigging fishing vessels showed obviously bimodal distribution. 2) The period from January to April was the major squid jigging fishing season and the fishing effort was the highest. The fishing intensity of vessels from mainland China was high from February to April, and the vessels from other countries and regions mainly fished in April and May. 3) The monthly fishing effort was spatially autocorrelated and showed patterns of significant aggregation. 4) The analysis of cold and hot spots reveals that the fishing effort in the survey area showed an aggregated distribution in both high and low values, and the fishing hotspots were moving southward from January to May.