Quantifying the spatial nonstationary response of environmental factors on purse seine tuna vessel fishing.

To investigate the spatial and temporal patterns of environmental factors influencing the activity of purse seine tuna fishing vessels, data on fishing efforts of purse seine tuna fleets and environmental factors in the Western and Central Pacific Ocean (WCPO) from 2015 to 2020 were utilized to develop a geographically weighted regression (GWR) model. The results showed that fishing activity was primarily concentrated in the area between 140°E and 175°W, and between 10°S and 5°N. The GWR model showed excellent fitting performance and was suitable for correlation analysis. The environmental factors had a significant spatially heterogeneous effect on the fishing activity of purse seine tuna fishing vessels. The sea surface temperature, primary productivity at 200 m depth, and dissolved oxygen below the surface had the greatest spatially heterogeneous effect and are important environmental variables influencing the activity of purse seine tuna vessels in the WCPO. This study provides new methods for exploring the spatial distribution of fishing vessel activity to support science-based conservation and management.