Effect of Different Stimulation Methods on Colony Survival and Development of Bombus haemorrhoidalis Smith in Himachal Pradesh

One of the key steps to facilitate year-round rearing of bumblebees is to break diapause period. In the present investigations, different stimulation methods were evaluated viz., cold temperature and CO2 narcosis, and their effects on colony parameters were studied. The daughter queens collected during winters were exposed to low temperatures i.e. 4±0.5 ° C for two months. But this did not show any results as all the queens died after two months. Another method used was exposing the queens with single and double CO2 narcosis. The present study concluded that bumblebee workers kept along with double narcotized queens was one of the best stimulation methods followed by single narcotized queens kept along with bumblebee workers.