Top: A 3-part drone frame, as used in the hives. The comb on the left is the oldest (3 weeks) and will be cut out. The right hand one is about 1 week old, the middle 2 weeks.
Bottom left: We put the comb in the freezer and examine its contents by breaking open the frozen comb a couple of days later. So far, we have see very little evidence of varroa.
Bottom right: The broken up pieces are fed to the birds – the magpies are usually first in line and clean up this feast within 10 to 15 minutes.
15 July 2016
One of the least pleasant tasks in my humble opinion is tackling varroa with the use of drone frames – effective though it may be.
The theory behind this method is that the varroa mite prefers a drone cell to an ordinary worker cell, as the period from egg to life of the drone (24 days) is similar to the varroa mite. For this reason, we insert an initially empty drone frame into the hive. The bees build their own comb (with large cells) and the queen lays drone eggs in them. Every week, we cut out the oldest of the three frames, wrap it in a plastic bag (marked with the colony name) and put it in the freezer. A couple of days later, we examine the combs by breaking them into smaller pieces. I always feel like a murderer when I look at the dead drones, but if it saves the colony from a far worse fate (dying in winter from being weakened by the presence of varroa mites) then so be it. (So far, I have not spotted a single mite, so we don’t seem to have the same varroa problem as we had last year.) Afterwards, I take the pieces out into the garden – at least it makes the birds happy!