Funct. Ecol. http://doi.org/cr2t (2018)
Insects are ectothermic (they regulate their body temperature using the environment), so many aspects of their biology and physiology are strongly influenced by environmental temperature. They are therefore expected to be sensitive to climate change — especially in warm environments where individuals are already functioning close to their thermal safety margins.
Paul J. CaraDonna, from the Chicago Botanic Garden, and co-authors investigate the effect of warming on a solitary bee species (Osmia ribifloris (Megachilidae)) in a warm, arid region of the southwestern United States. Their two-year field experiment uses nest boxes that were painted either white, to cool them, or black, to warm them to emulate past (around 1950) and future (2040–2099) temperatures from larval development to emergence.
Bees in the warmed treatment had delayed emergence phenology and a substantial increase in phenological variance. Higher temperatures also lead to reductions in body mass and fat content and 30–75% higher mortality. These findings suggest that O. ribifloris may face local extinction in the warmer parts of its range within this century. This case illustrates the potential risk of climate change to already-stressed pollination services.