The greater wax moth (Galleria mellonella) is the most serious and destructive insect pest of unprotected honey bee comb in warmer regions. Wax moths primarily infest stored equipment but will invade colonies whose worker bee population has been weakened by disease, queenlessness, failing queens, pesticide kills or starvation. However, many people outside of the beekeeping industry consider wax moths a beneficial insect because the larval stages are used as fish bait and for feeding insects in zoos.

Newly hatched larvae are white but successive instars are medium to dark gray on the top with creamy white undersides. The larval head capsule is brown. Wax moth larvae prefer dark combs because they contain a variety of nutrients such as entrapped pollen and larval skins. The larvae grow rapidly and will migrate toward the edges of the frames or corners of the supers to spin a cocoon and pupate.

Damage occurs as the larvae burrow into the comb feeding on the wax, larval skins, pollen and honey. As the larvae chew through the comb they spin a silk lined tunnel through the cell walls and over the face of the comb. These silk threads can tether emerging bees by their abdomens to their cells and they die of starvation because they are unable to escape from their cell. This phenomenon is termed galleriasis. In severe infestations, the wax comb, wooden frames, and sides of the hive bodies can be heavily damaged.

The most effective method for preventing wax moth damage in hives occupied by bees is to maintain strong colonies. The bees will remove the moth larvae and repair the damage as it occurs. Stored equipment can be protected against wax moths by fumigating it with paradichlorobenzene crystals or by stacking honey supers in a criss-cross fashion in open sheds. The penetrating air and daylight discourage colonization by moths. Some beekeepers store supers in enclosed barns with a lighted bug-zapper running constantly to kill emerging adult moths. This practice can eventually eradicate moths from the room.

Honey Bee Disorders / UGA Honey Bee Program / UGA Entomology Department