Predicting negative Effects of Climate Change on Taiwan's endemic Bumblebee Bombus formosellus.

Introduction: Climate change is threatening biodiversity hotspots. Notably, alpine bumblebees, which are mostly associated with a cold ecological niche, face a higher risk of extinction. Bombus formosellus is one of the alpine bumblebees endemic to Taiwan. Aims/Methods: In this study, we use ensemble ecological niche modeling for the first time to predict spatial and temporal dynamics for habitats suitable to B. formosellus under current and future climate scenarios (representative concentration pathway, RCP 2.6, 4.5, and 8.5 in the 2070s). Results: This model identified that the cool temperature with low variation, a specific range of precipitation and presence of coniferous forest and grasslands were the key factors affecting the distribution of B. formosellus. Using modeling to predict suitable habitats under various scenarios, we discovered that, compared with the current climatic conditions, the predicted suitable habitat area in the future decreased regardless of which climate change scenario was applied. In particular, RCP 8.5 appeared to be the most significant, with an area loss of nearly 87%, and fragmentation of the landscape with poor connection. Discussion: In summary, our analyses indicate that cool environments are suitable for B. formosellus. However, Taiwan's warming is more significant in the high mountains than in the plains. The climate change trajectory may become increasingly unfavorable to B. formosellus. Consequently, this species may face the risk of extinction in the future. Implications for insect conservation: We predict that many suitable habitats of B. formosellus will disappear or become fragmented in the future. Therefore, the remaining patches have become important refuges, and protection measures in these areas should be strengthened. [ABSTRACT FROM AUTHOR]