Spatio-Temporal Distribution of Four Trophically Dependent Fishery Species in the Northern China Seas Under Climate...

Climate change is a major challenge affecting marine environments, making it essential to understand species distribution responses in both time and space for effective conservation strategies. Meanwhile, varying responses of species to climate change may lead to changes in interspecific relationships and future spatial distributions. This study assessed spatial and temporal distributions of four trophically dependent species of economic importance in the China seas, including largehead hairtail (Trichiurus lepturus), Spanish mackerel (Scomberomorus niphonius), chub mackerel (Scomber japonicus), and anchovy (Engraulis japonicus). By incorporating fishery-dependent survey data and environmental variables, we developed a spatio-temporal mixed-effects model to analyze the distributional correlations among these species and predicted their distributions by the end of the century under different climate change scenarios. The results showed that the selected environmental factors influenced encounter probability and catch rates differently. Predictions for the end of the century under representative concentration pathways (RCPs) 2.6 and RCP8.5 suggested significant shifts in population densities, with species like T. lepturus and S. niphonius experiencing reduced densities and altered spatial patterns, while E. japonicus may benefit from climate change. The center of gravity for most species was projected to shift northward by the year 2050, with notable variations under RCP8.5. Additionally, spatial overlap among species was expected to decrease significantly by the year 2100, indicating increasing divergence in their distributions. This study underscores the effects of climate change on species habitat distribution and offers a scientific basis for future habitat protection.