Abstract:

In this study, we investigated the diversity of bumblebees and their floral resources during the late flowering season across 19 meadows near Shangri-La city in Northwest Yunnan, a renowned global biodiversity hotspot. We calculated the diversity index for bumblebees and measured several variables related to landscape structure and configuration for each meadow. Generalized linear models revealed that bumblebee abundance and species richness were primarily influenced by local floral resources, whereas the Shannon diversity index was largely determined by landscape variables, especially the percentage of woodland coverage. We further analyzed bumblebees with varying body size and tongue length, as these traits may influence responses to local and landscape variables. Notably, large-bodied bumblebees showed greater sensitivity to surrounding landscape variables in relation to flight capabilities, while small- and medium-bodied bumblebees were more dependent on local floral resources and habitat connectivity. Regarding tongue length, short-tongued bumblebees predominantly utilized local floral resources, whereas medium- and long-tongued bumblebees leveraged resources more extensively at the landscape scale, reflecting their different foraging strategies. This study illustrated the significant impact of flower availability and landscape characteristics on bumblebee diversity, highlighting how flight ability and foraging strategy profoundly influence the environmental dependence patterns of different bumblebees.