Long‐Term Climatic Variations Influencing Fish Stock Population Dynamics and Future Projections for Sustainable Fisheries Management

ABSTRACT This study aims to evaluate the influence of long‐term variations in sea surface temperature (SST), salinity, and pH on marine fish catch and species composition in coastal India. Secondary data (during 1985–2022) on oceanographic parameters were sourced from NOAA, while fish catch data of Bay of Bengal (BoB) and Arabian Sea (AS) were obtained from Central Marine Fisheries Research Institute (CMFRI). The Shannon–Wiener diversity index analysis and different forecasting models (ARIMA, Linear, and Polynomial) were employed for temporal forecasting till 2051. Diversity index results indicated that Elasmobranchs (3.24) were the predominant commercially important (CIF) taxa in both BoB and AS, whereas Threadfins and Flatfishes (3.20) dominated the trash fish (TF) assemblage in BoB, and Bombay duck (3.24) was the most abundant TF species in AS. Forecast projections revealed an initial decline in CIF and TF stocks in BoB, followed by a gradual recovery until 2051, while AS exhibited a consistent increase. These findings underscore the necessity for adaptive marine resource management and blue economy strategies to ensure sustainable fisheries under changing climatic conditions.