Bumble bees can sleep just about anywhere, but they prefer to nest in pre-existing cavities that offer insulation and protection from the elements. These include old rodent burrows, bunch grasses, or – as in the case of this photo of a bumble bee napping on a mule's ears (Wyethia angustifolia) – man-made structures like bird houses and even the cotton batting from old furniture. Unlike wasps and carpenter bees, bumble bees rarely cause any physical damage when they nest in human-built spaces.
During the night, a bumble bee can be found hanging upside down under the head of a flower, clinging to it with its mandibles, or simply resting on it1. When a bee is in deep sleep (pictured here, on a garden bumblebee (Bombus hortorum)), its antennae droop downwards and its wings are relaxed.
Female bumble bees lay unfertilized eggs that develop into males, who forage for food and pollinate flowers on their own. After the queen lays her own eggs, she retires to a spot away from her nest to hibernate through winter. The following spring she will emerge from a burrow to begin a new colony.
If you find a bumble bee nest that is inconvenient to your gardening or farming activities, we encourage you to build a barrier around the site using chicken wire or garden netting. Make sure it is high enough that children or pets cannot reach it, and be careful not to disturb the bees by moving their nest at night or early in the day when they are most active.