Historical, current, and future climate niche of the red dwarf honey bee across its native range

Knowledge of spatial patterns of climatically suitable habitats, and species range contractions/expansions, or shifts due to changing climate are important to improve the effectiveness of conservation efforts. Ecological niche models (ENMs) are the primary tools currently available for evaluating species’ response to anthropogenic or natural changes. We used ENMs to evaluate potential effects of future climate changes on the distribution range of a keystone pollinator, <i>Apis florea</i> Fabricius 1787 (Apidae: Apini), across its native range. We also provided a picture of the potential paleodistribution range of this species to complement future genetic/phylogenetic studies. In all assessed scenarios (i.e past, current, and future), the species was limited to its current native range and the mean temperature of the coldest season was the most key determinative factor affecting the species’ climate niche. The projection results revealed that the extent of climatically suitable habitats of the species was probably more than current in the past time periods and will increase in the future. Our findings of the consequences of climate changes on geographical distributions of this pollinator facilitate future management efforts for the species conservation by the identification of potential habitats where <i>A. florea</i> may already exist, prioritizing key habitats within the species’ native range under the current and future conditions, and recognizing regions where it is likely to spread its range.

明晰气候适宜栖息地的空间分布格局，以及气候变化驱动下物种种群分布范围的收缩、扩张或迁移，对提升物种保护工作的成效至关重要。生态位模型（Ecological Niche Models, ENMs）是目前学界用于评估物种对人为或自然环境变化响应的主要工具。本研究利用生态位模型，评估了未来气候变化对其原生分布区内关键传粉者——小蜜蜂（*Apis florea* Fabricius, 1787，蜜蜂科Apidae: 蜜蜂族Apini）——分布范围的潜在影响；同时还还原了该物种潜在的古分布范围，以期为后续的遗传学/系统发育学研究提供参考。在所有评估情景（即过去、当前与未来）中，该物种始终局限于其原生分布范围，而最冷季节平均气温是影响其气候生态位的核心决定性因子。模型投影结果显示，该物种的气候适宜栖息地面积在过去时期大概率高于当前水平，并将在未来持续扩张。本研究关于气候变化对该传粉者地理分布影响的发现，可为该物种的保护管理工作提供有力支撑：具体包括识别小蜜蜂（*A. florea*）已潜在分布的栖息地、优先保护当前及未来情景下该物种种群原生分布区内的核心栖息地，以及明确该物种未来可能扩张分布的区域。