Greater and Lesser Wax Moth
Krankheiten
Two species of wax moth occur in Central Europe: the greater wax moth Galleria mellonella and the lesser wax moth Achroia grisella.
Two species of wax moth occur in Central Europe: the greater wax moth Galleria mellonella and the lesser wax moth Achroia grisella. The adult moths do no damage; they merely lay eggs in cracks in hives and comb stores. The damage is done by the larvae, which feed mainly on pollen remains, on the cocoons of emerged bees, and on the molted skins in dark brood combs.
An infestation can be recognized by silken tunnels over and in the combs, by fine droppings in the form of small dark grains, by chewed-through foundation, and by destroyed cell walls. In extreme cases nothing is left of a brood comb but a clump of webbing. In the bee colony itself an infestation usually only becomes visible once the colony is too weak to occupy and defend the combs. A strong colony keeps the wax moth in check by itself.
The real problem is the comb store. In summer warmth the larvae develop quickly; dark brood combs with pollen remains are particularly at risk, while light combs that have never held brood are hardly attacked. Prevention therefore means: melting down old brood combs promptly, storing combs in a light, cool, dry, and airy place, for example in open stacks with a draft, 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 safe for bees. Combs can also be disinfested by cold by deep-freezing them for a sufficiently long time. Burning sulfur over empty combs in closed rooms is a classic method, but it does not work against the eggs, so the treatment has to be repeated at intervals of about ten to fourteen days.
Agents that accumulate in the wax and can pass into the honey, such as paradichlorobenzene, are not to be used. Such residues are unacceptable 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 in the open at the apiary. There is no notification requirement.