Greater and Lesser Wax Moth
Krankheiten
Two wax moth species occur in Central Europe: the Greater Wax Moth Galleria mellonella and the Lesser Wax Moth Achroia grisella.
Two wax moth species occur in Central Europe: the Greater Wax Moth Galleria mellonella and the Lesser Wax Moth Achroia grisella. The adult moths cause no damage themselves; they only lay eggs in cracks of hives and comb storage. The damage is caused by the larvae, which feed mainly on pollen residue, on the cocoons of hatched bees, and on the molted skins in dark brood combs.
Infestation is recognized by webbing tunnels over and inside the combs, by fine droppings in the form of small dark grains, by chewed-through foundation, and by destroyed cell walls. In extreme cases, only a clump of webbing remains of a brood comb. Infestation of the honey bee colony itself usually only becomes apparent once the colony is too weak to occupy and defend the combs. A strong, populous colony keeps the wax moth in check by itself.
The actual problem is the comb store. In summer warmth, the larvae develop quickly; dark brood combs with pollen residue are especially at risk, while light combs that have never held brood are barely affected. Prevention therefore means: rendering down old brood combs promptly, storing combs in a light, cool, dry, and airy place, for example in open towers with airflow, and consistently renewing the comb stock.
For treating stored combs, the biological preparation based on Bacillus thuringiensis is suitable; it acts against the larvae and is bee-safe. Combs can also be disinfested by cold, by deep-freezing them for a sufficient length of time. Sulfuring empty combs in closed rooms is a classic method, but it does not work against the eggs, so the treatment must be repeated at intervals of about ten to fourteen days.
Using agents that accumulate in the wax and can pass into the honey, such as paradichlorobenzene, should be avoided. Such residues are not acceptable in beekeeping, because wax stays in circulation. Likewise, infested combs should not be hung in healthy colonies, and comb waste should not be left lying openly at the apiary. There is no reporting requirement.