From thermal tolerance to distribution resilience: Physiology-informed species distribution models moderated range shifts for an intertidal crab species under climate change

The intertidal zone, occupying the critical interface between marine and terrestrial ecosystems, exhibits heightened sensitivity to climatic variations with accelerated ecological dynamics under dual environmental forcing. Species Distribution Models (SDMs), which establish statistical correlations between species occurrence records and environmental parameters, have become predominant tools for projecting biogeographic patterns under climate change scenarios. However, traditional SDMs frequently receive criticism for disregarding species-specific physiological constraints in environmental response mechanisms. Incorporating empirical physiological thresholds is therefore imperative for enhancing model biological realism and predictive accuracy. To date, this integrative approach remains unexplored for the Asian shore crab Hemigrapsus sanguineus (Crustacea: Varunidae), a keystone intertidal crustacean widely distributed along China's rocky coastlines. In this study, we developed novel Functional SDMs (F-SDMs) through the integration of thermal performance curves derived from laboratory experiments with ensemble SDM frameworks. Comparative analyses were conducted on both model predictive capacity (AUC/TSS metrics) and projected habitat shifts under Shared Socioeconomic Pathway scenarios. Our results demonstrate that physiological integration improved the predictive performance of the models, and F-SDMs predicted habitat changes were more moderate than traditional SDMs. These findings underscore the critical role of experimental physiology in marine biogeographic modeling, providing valuable information for predicting the distribution changes of marine species.