Varroa Mite

The Varroa mite is a nasty little sucker (literally). Also known as the Vampire mite, the Varroa mite survives by drinking the blood of honeybees. The mite attaches itself to the outside of the bee and sucks its blood. These "vampires" are quite a problem for bees and beekeepers, for the mite not only sucks the blood of the honeybee, but also spreads the Deformed Wing Virus as well as the Israeli Acute Paralysis Virus (IAVP). The Varroa usually strikes during the fall, and sign of an infestation often spells doom for the colony.  Varroas, along with their (IAVP) baggage, are the prime suspects for the cause of the potentially disastrous Colony Collapse Disorder.

Varroa mite on back of bee

It's very easy to detest these pests. They are annoying and they sting. While there are a lot of people who are afraid of honeybees, honeybees serve a purpose. A rather important and expensive purpose, at that. The Varroa mite serves virtually no purpose at all. Its sole reason for existence is to feed off the blood of honeybees, which inevitably destroys the colony. Parasites! Vampires! Kill ‘em all, I say. Unfortunately, this may be easier said than done. 

Upon closer inspection, the Varroa mite has a reddish-brown color, kind of like dry blood. Seems fitting. They are flat and are shaped like a button, approximately the size of a head of a pin. Like all mites, which belong to the Arachnid class, they have eight legs.

The female mite infiltrates a bee brood cell, and while the bee is still in its larvae stage, the mite lays her eggs on the bee larvae. The duration of the reproduction cycle take around ten days. The egg usually renders a few females and only one male. When the bee has matured and leaves its cell, the mites make their move to other bees in the colony, preferring drones.

The mite population grows or declines depending on its access to a brood. Rapid reproduction is one of the reasons why this mite is so dangerous. Another reason it is a threat to a colony is due to the timing of its infestations. The Varroa usually makes its move in the fall, which is when drone production ceases. The mite migrates over to the workers, who are the live blood of the colony. When this happens, the hive’s days are numbered.

Varroa mite on bee larvae

European honeybees, which are the dominate species in Europe, and North & South America, are for the most part, defenseless against the Varroa. There is some evidence of the Russian honeybee and some eastern honeybee species, putting up a fight. There is only a 50% chance that the Russkies will support mite production. Even Russian honeybees are tough. Must “bee” the weather. Ok, bad joke, moving along now.

The Eastern honeybee has developed methods of grooming that remove the parasite. Keep this in mind for later. Note: Varroas attach themselves to flower feeding insects such as Bumble Bees and Scarab beetles. Yet, in these cases, reproduction is impossible and the Varroa is just along for the ride.

Now that we are properly acquainted, let’s find a way to get rid of the Varroa. First, there are miticides, which when properly used, will slow the development of resistance of the mites. Some synthetic miticides include pyrethroid insecticides and organophosphate insecticides. Then, you have some natural occurring miticides like sugar esters, food-grade mineral oil and thyme oil. When using miticides it is important to be careful during application to avoid contaminating any honey. 

If chemicals aren't you cup of tea, there are some non-chemical methods to consider. First, there is the use of screened bottom board. By placing a mesh screened board on the floor of the hive, mites that fall off their hosts fall through the mesh and are not able to get back to the hive. The screened bottom board also has an additional benefit to the hive, increasing circulation, which helps reduce condensation at wintertime.

Freezing the brood kills some of the brood, but also kills the mites. Since most hives have more than enough drones, the initial loss can be overcome.

Hygienic Behavior, which is rather cool, is another mite remedy. Remember the Eastern species and how they groom the mites off their bodies? Well, that behavior can be bred, giving bees specific behavior traits, such as those of the Eastern honeybee. The bees are trained to smell Varroa infected brood, which the bees remove before the infestation spreads. Adapt and overcome.