Heavy infestation of several mites per cell kills the developing pupae. Adult male mites are much smaller and lighter. Their flattened body allows them to hide between the bee's abdominal segments or between body regions where they feed on the bee's blood. Female mites enter honeybee brood cells shortly before cells are capped, feed on the larvae, and lay eggs. Adult mites develop in six to 10 days and mate in the cells before emerging with the bee.
Male mites die soon after mating.
In late fall and winter most mites are found on the adult workers. Unchecked infestations can kill colonies in as few as three years. Colonies infested with varroa mites can be treated by means of Apistan strips. These strips are available from most beekeeping supply distributors. Remove honey supers and place two Apistan strips in the brood area of the hive.