Data from: Combined exposure to sublethal concentrations of an insecticide and a fungicide affect feeding, ovary development and longevity in a solitary bee

Pollinators in agroecosystems are often exposed to pesticide mixtures.
Even at low concentrations, the effects of these mixtures on bee
populations are difficult to predict due to potential synergistic
interactions. We orally exposed newly-emerged females of the solitary bee
Osmia bicornis to environmentally-realistic levels of clothianidin
(neonicotinoid insecticide) and propiconazole (fungicide), singly and in
combination. The amount of feeding solution consumed was highest in bees
exposed to the neonicotinoid, and lowest in bees exposed to the pesticide
mixture. Ovary maturation and longevity of bees of the neonicotinoid and
the fungicide treatments did not differ from those of control bees. In
contrast, bees exposed to the pesticide mixture showed slow ovary
maturation and decreased longevity. We found a synergistic interaction
between the neonicotinoid and the fungicide on survival probability. We
also found an interaction between treatment and emergence time (an
indicator of physiological condition) on longevity. Longevity was
negatively correlated to physiological condition only in the fungicide and
the mixture treatments. Delayed ovary maturation and premature death imply
a shortened nesting period (highly correlated to fecundity in Osmia). Our
findings provide a mechanism to explain the observed dynamics of solitary
bee populations exposed to multiple chemical residues in agricultural
environments.