Impact of Climate Warming on Oncomelania hupensis in China- Multi-scale Evidence

Background Climate warming is increasingly reshaping the population dynamics of Oncomelania hupensis , the sole intermediate host of Schistosoma japonicum in China. Investigating the response of O. hupensis to climate warming is crucial for guiding targeted and precise interventions against these snails, thereby accelerating progress towards schistosomiasis elimination in China. Method We conducted temperature-controlled laboratory experiments to quantify survival, body size, and body weight responses of individual O. hupensis under non-optimal temperatures. We then developed sliding-window models based on long-term (1990–2022) population surveys and climate data, examining climate exposure across its life stages to assess population-level responses to climate warming; and used general linear mixed-effect models to explore the environmental factors of climate responses (geographic: latitude, longitude, altitude, land use, historical climate variety). Model performance was evaluated to identify the best predictive models, which were subsequently used to project future O. hupensis density under the SSP1-2.6, SSP2-4.5, and SSP5-8.5 scenarios. We further sampled 240 wild O. hupensis and measured their body sizes. Results At the individual level, we observed that larger snails had a higher survival rate at non-optimal temperatures but experienced a significant loss in body mass compared with the control group. At the population level, O. hupensis density closely tracks climate warming, with 91.964% of populations showing positive temperature sensitivity. Exposure during the coldest and breeding seasons had a greater influence on O. hupensis density with climate warming. O. hupensis in waterbody-dominated areas showed the largest density growth rates, whereas crop populations were the most sensitive to land cover. At the ecosystem level, only 18.968% – 24.610% of populations were expected to benefit from climate change by 2100, and these benefiting populations were concentrated in regions where sampled wild snails had a mean body size of 8.195 mm. Crop accounts for 71.953% of populations benefiting from climate warming, compared with 17.169% in forests and 8.257% in impervious-dominated areas. Conclusion The O. hupensis population benefited from climate warming but was regulated by land-use types. To mitigate the impacts of climate warming and land-use on snails, surveillance and integrated interventions should be strengthened through multi-sector collaboration.