Diurnal Temperature and Time Affect Visitation Patterns of Honey Bees

Temperature is one of the most important environmental factors affecting honey bee activity, while ambient temperature varies widely during the daytime. We speculated that the daily visitation patterns of honey bees were closely related to the time of day and temperature. Our understanding of the effects of ambient temperature and daytime on visitation patterns of honey bees is limited. Here, we surveyed the visitation rate of honey bees (both Apis cerana and Apis mellifera) to flowers of 14 cultivated species and compared the visitation patterns of honey bees concerning diurnal temperature and time. Our observations suggested that diurnal temperature variation was significantly positively correlated with the visitation rate of honey bees only in three plant species. Honey bees began visiting flowers when the ambient temperature exceeded 16 °C. The optimal temperature range for foraging of honey bees was 38- 42 °C. The maximum average temperature occurred between 1300-1400 h, while the optimal visitation time for honey bees was 1400-1500 h, which did not correspond to the maximum average temperature. Our results suggested that the visitation patterns of honey bees were affected by both the time of day and temperature. Honey bees tended to visit more flowers in the noon and afternoon when the temperature was higher than in the forenoon