Thermal preferences of honey bee drones at different ages, depending on the rearing temperature

The thermal preferences of honey bee drones change with their age as a result of sexual maturation. However, the factors influencing them are still unknown. For this reason, the aim of this study was to assess the effect of the rearing temperature during the post-capped development of drones on their body mass at eclosion and thermal preferences. Combs with capped brood of drones from three colonies were kept in incubators in changing temperatures from higher to lower (35–33 °C) or from lower to higher (33–35 °C). After emergence, drones were individually weighed. Subsequently, their thermal preferences were tested at the ages of 1, 5, 10, 15, 20, and 25 days. Body mass at eclosion and thermal preferences of drones significantly depended on the rearing temperature and maternal colony. Drones reared in temperatures changing from higher to lower (35–33 °C) were considerably heavier after emergence compared with those reared in temperatures changing from lower to higher (33–35 °C). The thermal preferences of drones also changed with their age. The greatest differences in thermal preferences of drones from both groups (35–33 °C and 33–35 °C) were on the 5th and 15th days of life. These findings indicate that rearing conditions (temperature and colony) influence the body mass at eclosion and thermal preferences of drones.