Wax moths are parasitic insects that can cause severe damage to woodenware and comb. A healthy colony will often fight off these pests, but not always.
Beekeepers should make every effort to prevent wax moths from living off their hive’s resources. Here are some simple ways to keep them away from hives and stored frames.
How can beekeepers prevent wax moths in active hives?
The best options for staving off wax moths are to keep a healthy hive, understand the signs of wax moth, and maintain clean, tidy equipment.
It is also important to keep space in the hive to a minimum to reduce the area your bees must defend.
Choosing a bee breed with the right genetics and freezing suspect hive equipment before use will also go a long way towards keeping wax moths away.
1. Keep a healthy colony
As you’d expect, a thriving, populous colony of bees does a great job of housekeeping. Unwanted guests like adult moths and larvae are quickly dealt with before the situation worsens.
Effective colony management will help colonies flourish. Choosing the right bee breed for the location and correct hive placement are worth considering. Ensuring the hive has a young, prolific queen will also get your bees off to a good start.
A weak colony may be better united with a stronger one, especially if the colder months are fast approaching.
2. Understand wax moth signs
Confidently identifying the signs of wax moth will allow beekeepers to give a helping hand when needed. Swift removal of larvae and reducing space in the hive will hinder a moth invasion.
Helping the colony is difficult if you don’t know what these parasites look like. We suggest reading our guide on how to detect wax moths for more advice in this area.
3. Maintain a tidy hive
Clean hives reduce the chance of a visit from wax moths. Leftover debris provides a good hiding spot to escape detection, so removal is essential. It is good practice to clean bottom boards and other hive equipment each year.
Old comb, leftover beeswax, and slum gum should be removed to maintain a clean environment. Any items previously infested should be treated, frozen, or destroyed.
Hive tools are handy for cleaning up pre-used empty boxes. Use them to scrape off leftover moth cocoons.
4. Reduce space
Beekeepers do their bees an enormous disservice by adding extra honey supers too early. Unused hive space is unsettling for bees, increasing the area they must defend.
It is vital to maintain a high ratio of bee-to-comb. Only add additional supers as the colony grows. This rule is especially important in summer and fall.
5. Selective genetics
Some breeds of honey bees have a genetic disposition towards hygienic behavior. Pure Buckfast and Russian bees are excellent housekeepers. They have a good tolerance to common honey bee pests and will remove debris that wax moths hide in.
While there are no guarantees that your bees will always fight off wax moths, some breeds will help improve the odds.
6. Freezing hive equipment
No beekeeper wants to introduce boxes suspected of having wax moths. A safe way to avoid spread is to freeze any equipment or boxes for two days before use. The extreme cold will kill wax moth adults or larvae.
Never store recently extracted supers in trash bags. If wax moth eggs have gone unseen, the comb will be destroyed by the time it gets opened again.
Tip: Discover the lifecycle of a wax moth here.
7. Build solid hives
If you build your own hives, ensure there are no gaps. A combination of nails and glue will help create a tight fit.
Well-built hives without gaps will make it harder for wax moths to slip inside. Any openings will mean the colony has to defend another entry point.
How to prevent wax moths infesting stored comb
1. Ventilation and light
Wax moths thrive in dark places with limited space, so beekeepers can use this knowledge to create a hostile environment.
A proven strategy for restricting wax moth infestations is to store frames of drawn comb in well-ventilated rooms with plenty of sunlight.
Supers containing drawn comb should be spaced apart to allow airflow between them. Allow at least one inch of space between each one. This practice prevents heat from rising to a level that promotes the development of wax moths. (Popolizio & Pailhe 1973).
Note: Don’t use light and ventilation to control wax moths that have already infested comb.
2. Proper frame management
Managing hive supers and frames the right way will repress wax moth invasions. Implementing a few simple processes will help keep hive resources in a healthy condition.
Wax moths target honey supers recently removed from the hive. To minimize the window of opportunity, always extract honey from supers within 48 hours of removal.
Drawn comb should never be left in a hive without bees. Immediately transfer it to an occupied hive or storage, ready for extracting.
When wax moths are active, avoid adding too many wet supers to a hive for cleanup. Adding them to a weak colony is also bad practice.
3. Maintain brood-free supers
Wax moths love remnants of brood such as larval skins and pollen. They provide a valuable food source that assists with moth development. Using a queen excluder in the hive helps keep brood and honey supers separate.
4. Apply PDB
Traditional moth balls contain naphthalene which can harm bees and isn’t recommended for dealing with wax moths. Para-dichlorobenzene (PDB) is suitable for keeping stored supers free from wax moths. It is a good option in summer and fall when cool rooms aren’t available.
PDB crystals will repel visiting moths from supers and stop eggs from getting laid on them. It will also kill any existing wax moths and larvae at any stage of development but won’t kill the eggs.
Stack supers about five high and tape them up to ensure no gaps. Place newspaper on top and then create a fumigation chamber by adding the recommended dose of PDB on top of the newspaper. Finally, cover the stack with a hive lid and allow the fumes to work their magic.
For better coverage, some prefer sprinkling PDB on each layer.
Necessary: Always air supers for 2-3 days before adding them to a hive.
The honey bee is good at removing wax moths from the hive – some races are better than others. Maintaining a healthy hive and doing the basics, like keeping equipment clean, will play a big part in fighting off wax moths. Choosing a bee breed that has good housekeeping may also make a difference.
Over the years, researchers have looked at creative ways to keep wax moths away. For example, at Clemson University, South Carolina, research looked at whether fire ants combined with good light and ventilation will offer protection. They concluded that this defensive combination provided excellent prevention (Hood et al. 2003). However, there are some obvious limitations and challenges with this strategy.
If you want to keep pests and diseases away from hives, we suggest reading our article on some major threats to bees.