Meeting Abstract
The foraging activities of bees and hornets are directly tied to their ability to 1) maintain a minimum thoracic temperature required for sustained flight and 2) their ability to diffuse heat so as not to overheat to a lethal temperature. In the face of climate change, the atmospheric conditions which contribute to heat gain and loss are changing rapidly globally, thereby changing the heat transfer dynamics and microclimate usage of endothermic hymenopterans. It is therefore important to understand, at a biophysical level, how meteorological conditions can extend or limit the thermal budget of these important pollinator species. Here, we present a heat transfer model for three hymenopteran species, the honeybee ,Apis mellifera, the bumblebee, Bombus impatiens, and the bald-faced hornet Dolichovespula maculata. The model is experimentally parameterized along the major routes of heat gain and loss: convective heat transfer, absorption of solar radiation, metabolic activity, evaporative water loss, and radiative heat transfer. Then, using physiological data on the minimum internal temperatures needed for flight and the maximum temperature before lethal overheating, we solve for the time it will take workers of each species to reach either the minimum or maximum heat threshold under variable atmospheric conditions.
