Simple Summary Pollinators' features, especially those with a functional role during the
pollination process, have been shown to be a good predictor of pollen load for some bee
species, but little is known about solitary bees. Here, I have used two solitary oil-collecting
bees to understand the impact of functional pollinator traits on the pollen load of two oil-
secreting Calceolaria herb species. I therefore measured the visitation frequency, the time
spent manipulating the flower and the body size and pollen load for each bee species. The …