Before the brink: sublethal effects of climate warming on native bee ecology

Climates shape species physiological traits and geographic distributions. However, climates are changing, and some species are more vulnerable to warming climates than others. Vulnerability to climate change is often assessed by examining species lethal limits (e.g. critical thermal maxima). However, climate warming will impact species before they reach their upper critical thermal limits and become locally extinct. For example, species might be less active at warmer temperatures, could be unable to reproduce, or their physiological performance, which is often used as a proxy for fitness, could be impacted.

This project aims to examine how climate change is impacting Australian native bee species ecology and pollination ability. We will use flight performance, a critical life history trait for predator escape, pollination, resource acquisition, and dispersal to determine sublethal impacts of temperature on diverse native bee species that inhabit different geographic ranges. We will sample bees across the Australian native bee phylogeny within temperate, tropical, and arid regions in Australia (24 different species). We will identify the relationship between flight performance (speed and foraging distance) and temperature (thermal performance curves) for each species to predict how climate change is already impacting native bees. We will also identify the extent to which native bees can thermoregulate their body temperature during take-off and flight using thermal imaging camera during thermal flight performance trails.

This project will allow us to determine how increased anthropogenic warming will impact species fitness and geographic distributions, and will identify high conservation priority species, and which climatic regions across Australia are likely to experience the greatest loss of key pollinators. We will inform conservation managers and government on our results to boost the conservation of native bee species within Australia.