At this time of year bumble bee larvae develop into virgin queens and males instead of the female workers that hatch during the summer.  Chances are if you take an early morning walk when fall temperatures are starting to drop, you may come across one of the male bumble bees in an immobile state resting on a goldenrod or aster flower. Having spent the night here due to cold temperatures (their flight muscles must be above 86°F in order for them to take flight and their thorax must be maintained during flight at 86-104°F), they use their wing muscles in the morning to shiver and raise their temperature until they are capable of flight.

Young queens are visible during the day, but return to the hive for shelter during the night.  Once they have mated and are fertilized they fill their honey sacs with honey and seek shelter for the winter several inches underground.  They are the only members of the hive to overwinter; all others perish in the fall. (Photo: male bumble bee resting on New England Aster early one fall morning.)

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