The rate of supply of sucrose solution at an artificial food source was varied by means of a pump, while the concentration of the solution and the temperature at the food source were kept constant. The behaviour of the collector wasps was found to change in correlation with the supply rate, in several respects.
As rate of supply increases
- a) the duration of sojourn at the food source decreases;
- b) the volume of solution removed per h increases;
- c) the number of single visits during a sojourn and per h decreases;
- d) the duration of single visits increases, except that at extremely high supply rates the single visits become shorter.
The waiting time (Saugwartezeit) does not depend on supply rate.
Comparison of these wasp data with related observations of honeybees (Apis mellifera) supports inferences regarding the motivation of collector wasps and, in view of the frequency of their single visits, about their suitability as potential pollinators of the flowers from which they collect.