Varroa mites can infest a hive at different points of contact with a honey bee. Whether it is by hitchhiking on infested bees or multiplying in the hive, these mites will initially begin their life cycle by consuming blood on the backs of these honey bees. Once these honey bees eventually return to the hive, the varroa mite will find its way into an uncapped brood cell. The varroa mite will hide and wait until the bees cap the brood cell. When capped off, the mite will begin to feed off the developing larvae and eventually lay more eggs. When the brood honey bee emerges from the cell, the mites will emerge with it and infest other brood cells, multiplying at a rapid rate. The mite’s life cycle allows for the population to grow exponentially as the bee colony multiplies with the warmer seasons. The honey bee population will naturally start dwindling at the end of the summer and into the fall, leaving an overwhelming mite population that will eventually kill off the entire honey bee colony in the winter. Varroa mites have been considered a problem in beekeeping for about 40 years. Most recently, scientists and beekeepers have realized that Varroa infestation is more complex than originally thought. It began in Asia and slowly spread over in a course of 10 years to Western Europe and South America. Within an additional 10 years, the mites would spread to the United States. It turns out that viruses vectored by the mite may be a huge factor in honey bee colony losses. These mites are capable of spreading over 22 different diseases such as the deformed wing virus, one of the most viral diseases associated with these mites. Currently, there is no safe, easy and effective solution for beekeepers but the outlook for a treatment that is urgently needed will be heavily dependent on further research into mite biology and tolerance breeding.
For a comprehensive study on Varroa, see Biology and Control of Varroa destructor by Peter Rosenkranz a,*, Pia Aumeier b, Bettina Ziegelmann, The Journal of Invertebrate Pathology.