Integrating Thermal Resilience Thresholds and Endocrine Disruption Models to Predict Climate-Driven Reproductive Collapse in Clarias gariepinus Under Extreme Weather Events

Climate change-induced thermal stress and the mobilization of endocrine-disrupting chemicals (EDCs) pose synergistic threats to aquatic ecosystems. However, their combined impacts on hypothalamic-pituitary-gonadal (HPG) axis function remain poorly quantified. This study investigated thermal–EDC interactions using experimental thermal gradients (25–40 °C), LC-MS/MS steroid profiling, and machine learning models to predict reproductive collapse risk. Results identified a critical threshold at 35°C for aromatase suppression (P< 0.01), leading to a 60% reduction in estradiol synthesis and inducing gamete apoptosis (LT₅₀ = 4.2 h at 40°C). Monsoon simulations revealed a 3.2-fold increase in BPA bioavailability, correlating with serotonin depletion (r² = 0.78) and spawning failure. Machine learning projections under CMIP6 scenarios forecast an 18–22% decline in gonadosomatic index (GSI) by 2040, with tryptophan hydroxylase emerging as the primary resilience biomarker (importance score: 0.92). These findings establish a predictive framework for HPG axis collapse and underscore the urgent need to integrate thermal–EDC monitoring into aquaculture management strategies, particularly under IPCC SSP5-8.5 projections.