Weather Conditions Affect the Visitation Frequency, Richness and Detectability of Insect Flower Visitors in the Australian Alpine Zone

Abstract

Weather conditions, such as humidity, temperature, and wind speed, affect insect activity. Understanding how different taxa respond to varying environmental conditions is necessary to determine the extent to which environmental change may impact plant-pollinator networks. This is particularly important in alpine regions where taxa may be more susceptible to extreme climatic events and overall increases in temperature. We observed plant-flower visitor interactions in Australian alpine plant communities to determine 1) the structure of the plant-flower visitor community, and 2) how floral visitation and diversity of insect taxa varied according to environmental conditions and habitat type. Coleoptera and Diptera were the most dominant flower visitors in the visitation networks. Most insect orders were moderately generalized in their interactions, but Hymenoptera showed greater specialization (<i>d'</i>) at exposed sites compared to other insect orders. Importantly, insect orders behaved differently in response to changes in environmental conditions. Hymenoptera visitation increased with higher temperatures. Diptera was the only taxon observed actively moving between flowers under inclement conditions. Our results demonstrate the value in sampling across the spectrum of environmental conditions to capture the differences among flower visiting insect taxa in their responses to varying environmental conditions. A diversity of responses among insect taxa could facilitate community-level resilience to changing environmental conditions.