Capped+Drone+Brood+Cell+Removal+(GAZ)


 * Capped drone brood removal **

The process of removing capped drone brood cells from a hive is an efficient control method of //Varroa // populations. It requires the physical removal of combs from a hive, and in doing so removes developing //Varroa // within drone brood cells. The reason that this is such an efficient method has to do with the //Varroa's // biology. //Varroa destructor // mites spend the vast majority of their lifecycles in capped brood cells. It is in here that they are born, develop, mate and then later die. Further to this, while mites are able to reproduce in any brood cell, the frequency of mites can be as much as 5 – 12 times as often in cells with drone brood compared to those with worker brood. Finally, mites using worker brood as a host are less productive in terms of offspring production, averaging only 1.3 – 1.4 offspring while those using drone brood average 2.2 – 2.6 offspring. As you can see, the removal of capped drone brood removes a disproportionately large number of mites without affecting the worker population (Calderone 2005, 645).

Although this method does prove effective, the design of commercial hives lets it down. As mentioned previously, //Varroa // are able to reproduce in any honey bee larvae cell they can get into, but they tend to invade drone brood more readily than worker brood. This makes drone brood an especially effective trap for //Varroa // (van Engelsdorp et al. 2009, 2). Lifting out the heavy honey combs in order to get down to the brood cells is not an easy task. As a result, this control method has not been readily accepted by the majority of beekeepers yet but new hive designs are being developed which will facilitate easier removal of the brood nests. Once the brood nests have been removed, they are either destroyed (with the bees required to rebuild a new brood comb) or treated (for example, by heat). While not completely eliminating the //Varroa // infestation, this is an efficient chemical free method with no lasting side effects on the bee products (Cornell University 2006).



Images courtesy of [|Cornell University Master Beekeeper Program]