Data from: Against the odds: Nesting specialisation and foraging ecology provide insights into climate change responses in a mountain bee

Climate change is rapidly altering temperature regimes in mountain
environments, reshaping the distribution and activity of pollinators.
Studies of insect pollinator assemblages in mountains show a general
pattern of decreasing bee (Apoidea) activity with increasing
elevation. Here we report a unique Exoneura bee that counters
this trend and thrives in cold, high elevation (~1500-1900m a.s.l.)
woodlands at the tree line.  Whereas other members of the genus
at lower elevation nest in narrow pithy or hollow plant stems, this bee
has a unique nesting biology, burrowing into the dead branches of the only
tree in Australia’s subalpine zone (snow gum, Eucalyptus pauciflora subsp.
niphophila). Using a combination of observational surveys, spatial
mapping, temperature tolerance tests, and biophysical modelling, we
investigated various aspects of the bee’s ecology. We found that this
species’ nest abundance peaked at the tree line (approx. 1900 m a.s.l).
Foraging behaviour was highly dependent on the presence of snow gums for
nesting, with activity concentrated within 30m of snow gum stands.
Biophysical modelling showed that the daily and annual foraging activity
window was significantly limited by temperature, and that it will
substantially increase under climate change projections. This study
reveals several unique traits of a new bee species that shows a close
association with snow gums, providing insights into its flourishing in the
changing conditions of subalpine Australia’s high-elevation
environments.