Climate Change and Hydropower Impacts on Habitat Suitability of Endangered Schizothoracinae Fishes in the Qinghai‐Xizang Plateau

ABSTRACT

Climate change and human disturbance threaten freshwater biodiversity, particularly endangered species on the Qinghai‐Xizang Plateau. Oxygymnocypris stewartii , Schizothorax macropogon , and Schizothorax waltoni ( Schizothorax spp. hereafter) are Class II Protected Species in China, indigenous to the Qinghai‐Xizang Plateau, and primarily distributed in the middle and upper Yarlung Zangbo River (MUR). Based on species distribution points, the Maximum Entropy (MaxEnt) model was used to simulate potentially suitable habitats and identify key environmental factors for Schizothorax spp. Ecologically suitable areas were reconstructed using a kernel density estimation (KDE) algorithm that incorporates hydropower plants, and future distribution dynamics were predicted under various climate scenarios. Results indicated that the flow accumulation and the mean temperature of the coldest quarter were the primary environmental factors affecting Schizothorax spp. For Schizothorax spp., the suitable habitat exhibited a non‐monotonic trend: it increased before the 2050s (up to 108.28% at 2050s‐SSP7.0), then turned downward by the 2070s (18.1% at 2070s‐SSP2.6). Moreover, habitat suitability sustained expansion at the upper reaches, with the rate of expansion increasing with the intensification of radiative forcing, and projected an increase in elevation at SSP7.0 and SSP8.5. At the local scale, however, hydropower plants pose a deterministic threat, causing permanent habitat loss of Schizothorax spp. in the middle and lower reaches. Overall, the model predicts that future climate‐driven events may lead to a spatial expansion of potentially suitable habitats for Schizothorax spp. However, due to limitations in hydrological connectivity and the unique characteristics of fish, these high‐altitude habitats face significant constraints. Enhanced conservation efforts in the Saga, Angren, and Miling basins of the MUR are recommended, along with continuous monitoring and early warning of changes in habitat suitability to protect the Schizothoracinae conservation areas.