Comparing foraging behaviour of small and large honey-bee colonies by decoding waggle dances made by foragers

1. We compared the foraging behaviour of two small (approximately 6000 bees) and two large (approximately 20 000 bees) honey-bee colonies over 6 days. We determined where the bees of each colony foraged, whether they collected nectar or pollen, the number of patches foraged at, the number of bees engaged in foraging, and the concentration of the nectar collected. 2. Even though the colonies were located in the same environment and had the same genetic background, foragers from different colonies used different forage patches. 3. Small and large colonies foraged at a similar distance in July when forage was abundant (mean foraging distance for small and large colonies was 0.67 and 0.62 km, respectively) whereas the large colonies foraged significantly further in August when forage was scarce (mean foraging distance for small and large colonies was 1.43 and 2.85 km, respectively). 4. Small colonies foraged at approximately the same number of patches as large colonies. The total number of foragers returning to the small colonies per minute was significantly lower than the number of foragers returning to the large colonies. This means that, relative to their size, small colonies foraged at more patches than large colonies. 5. The quality of the nectar collected by foragers of the small and large colonies did not differ. However, small colonies did collect more pollen than large colonies.