Varroa Management

I cannot improve much upon the FERA Varroa Management guides, which can be downloaded here:

• Varroa Management
• Using Artificial Swarms for Varroa Control

They also have a useful Varroa calculator that I have used a few times.

My Varroa Management

Please read my Beekeeping Calendar for more information, but my interventions are:

• All Year – Open Mesh Floor
• April – Insert drone brood foundation. This is not described in the FERA guide but I have described it below and I found this technique described in the July 2014 BBKA journal written by The University of Georgia. I have found culling drone brood highly effective.
• Late July / August (after honey is removed) – Use Apiguard for 4 weeks
• December – Use Oxalic Acid (but only if it has been a cold winter and the hive is broodless – this requires 3 weeks at temperatures below 5C. I applied Oxalic Acid in December 2013 (mild winter) and it was not effective – so best not to use in these circumstances. Read: Applying Oxalic Acid)

Artificial and natural swarming will create periods of broodlessness and hence reduce varroa.

Using Drone Brood Foundation In April

1. In April insert a frame with drone brood foundation into the brood box next to the outer frame of brood
2. Remove when drone cells are capped (i.e. 17 days later if comb was already drawn)
3. Place frame in freezer for 24 hours or until frozen solid
4. Let frame thaw and then remove dead bees and larvae with uncapping fork
5. Put frame back in hive for bees to clean up
6. At this stage you can either (A) leave it in for another round of mite removal; or (B) replace with standard worker brood frame
7. Protect/store the frames for the next 12 months so that wax moth don’t get them

Rationale For My Approach To Varroa Management

• Open Mesh Floor evidenced as effective way to reduce varroa plus easy, cheap
• Three interventions a year should suffice (drone removal, Apiguard, Oxalic Acid)
• Using drone foundation is cheaper and easier than using comb cage to trap queen
• I prefer the idea of using drone foundation rather than inserting a shorter brood frame so I can then replace that frame with a standard frame for the colony to use more effectively
• Apiguard reduces varroa population by 95% and is less aggressive than MAQs strips. I have started removing all honey by late July / start August in order for the bees to be able to build up honey stores for the winter and to be able to use Apiguard which needs temperatures above 15C.
• Oxalic Acid is effective under broodless conditions and reduces varroa population by 90%. It’s also relatively cheap. From now I only use during cold winters (described above)
• Apiguard is about £5 per treatment/hive; Oxalic acid is about £0.50 per treatment/hive

Further Reading

I have written a how-to on Oxalic Acid Treatment.

Here are some of my posts on varroa:

• From 2,000 To 0 Varroa Mites In 8 Months
• Acid Resistant Bugs
• What Is Going To Kill Them First: Varroa, Starvation Or Me?
• Look No Smoke & A Varroa Problem