Statistical analyses and datasets for "Bumblebees collect a fixed sucrose intake per foraging bout rather than maximising collection volume"

ABSTRACT Bumblebees face the intricate challenge of collecting substantial quantities of sugar from various floral resources. Yet, it remains unclear how individual bees optimise nectar collection. Here we investigated how Bombus terrestris workers collect sucrose solution on mixed-quality flower patches. Individual bees were observed foraging in a flight arena containing artificial flowers arranged in half-blue, half-yellow patches over three consecutive foraging bouts. Yellow flowers were highly rewarding (40% w/w sucrose solution) while blue flowers were either poorly rewarding (20% w/w sucrose solution) or not rewarding. In both conditions, the bees significantly increased their sucrose intake rate by increasing their foraging speed and accuracy over subsequent foraging bouts. However, they maintained a consistent total absolute quantity of sucrose intake across the three bouts. In the condition where both flower types were rewarding, the bees collected lower volumes but increased their consumption of high-concentration sucrose solution over time. These findings suggest that bumblebees forage with a specific target for carbohydrates rather than maximising volume collection.