Predicted Changes in the Distribution Range of Apis cerana in Asia, Europe, and Africa Under Climate Change

Honeybees play vital roles in pollination, plant reproduction, agricultural productivity, and biodiversity. The Eastern honeybee, Apis cerana, is ecologically and economically important across South, Southeast, and East Asia. This study used an optimized Maximum Entropy (MaxEnt) model to assess current climatic suitability and potential future range dynamics of A. cerana across Asia, Europe, and Africa under SSP126, SSP245, and SSP585 scenarios for 2050 and 2070. The optimal model used the linear-quadratic-hinge (LQH) feature class with a regularization multiplier of 1 (RM = 1). Spatial cross-validation demonstrated strong and consistent performance, with mean AUC, TSS, and Continuous Boyce Index values of 0.852 ± 0.009, 0.617 ± 0.020, and 0.939 ± 0.013, respectively. Precipitation of the wettest month (Bio13) was the most influential predictor (~52%), followed by precipitation of the warmest quarter (Bio18) and mean diurnal range (Bio2). Current suitable habitats were concentrated mainly in South, Southeast, and East Asia. Future projections indicated a predominantly stable-to-expanding pattern of climatic suitability, with habitat gains generally increasing under stronger climate-forcing scenarios, particularly SSP585, while losses remained limited. Suitable habitats remained concentrated primarily across South and Southeast Asia, with additional suitable areas in parts of East Asia, Africa, and Australia. These projections represent potential climatic suitability rather than the realized distribution and provide a basis for monitoring potential expansions in climatically suitable habitat.