Bumblebee hitchhikers

Regular readers may remember my post about the first bumblebees and may remember this photo.

Some of you noticed the bee was carrying some little passengers and we were wondering if they would be detrimental to the bumble. I have since learned that these little mites are called phoretic mites (Parasitellus). The mites are just hitchhikers and will not harm the bee. They are a non-feeding nymph stage of the adult mites. They over-winter on the queen bees. Once the queen establishes a nest the mites drop off. They remain in the nest,  feeding on the nest detritus, a sort of live-in nest cleaner for the bees.