Mexican Freshwater Fish: Identifying Conservation Priorities and High‐Risk Areas for Fisheries Under Climate Change

ABSTRACT Freshwater fish are essential components of aquatic ecosystems, providing key ecological functions and supporting livelihoods. Climate change poses a significant threat to freshwater biodiversity; consequently, both its conservation and the food security it sustains may be at risk. Mexico harbours 677 native freshwater species, characterised by high levels of endemism and many taxa of economic and cultural importance. However, few studies have assessed the impacts of climate change on these species to inform conservation planning or identify high‐risk areas for fisheries. Here, we present the first comprehensive database integrating taxonomic, ecological and fisheries information for Mexican freshwater fish of socioeconomic relevance. Using historical occurrence records and ecological niche models under baseline and future climate scenarios (SSP245 and SSP585), we assessed past, present and projected distributions for 54 of the 56 species; the remaining two could not be modelled due to insufficient model performance even under relaxed thresholds. Our results aim to provide a baseline for identifying priority conservation areas and regions at high risk for fishing communities. Models suggest that tropical and eurythermal species may expand into new areas, whereas endemic and cold‐water taxa are projected to experience severe range contractions, with the potential losses of up to 86% even under the full‐limited dispersal scenario. Southeastern regions maintain high climatic suitability over time, potentially functioning as climatic refugia, while central basins show substantial declines, threatening local fisheries. Overall, our findings reveal marked spatial disparities in vulnerability and resilience, highlighting conservation gaps beyond the current network of Natural Protected Areas. Proactive strategies—including priority site designation and community‐based adaptation—will be essential to safeguard freshwater biodiversity and food security.