There has been a growing problem with honey bees dying off. The primary source of the problem isn’t pesticides as some might think (though that is a problem since it can apparently mess with hormones and make the bee lose its sense of direction), but a type of mite known as Varroa (also called “Vorroa” or “Varroa destructor”). The Irish Times reports: “the mites, in combination with other viruses, have killed off up to 30 per cent of Europe’s bees, and a whopping 85 per cent of Middle Eastern bee.” American bee keepers haven’t escaped either; an estimated third of American bees have been lost to the mite.
According to Ric Bessin, an entomologist at the University of Kentucky College of Agriculture, Varroa mites primarily attack the drones (males). The female mite enters the brood cell with the bee larva a day before the cell is capped and sealed. She then lays her young who feed with the bee larva after they hatch. By the time the bee hatches, the mites have already fully grown, mated, and go on to attack other drones. They don’t have much time to be a problem: the mite itself only lives on average 27 days.
The mites bite their victims, sucking out blood. These parasites can carry a deadly virus that are left behind after the bee is bitten and can (and often do) kill the bee. The disease, varroatosis, can kill a colony in 3 to 4 seasons.
Ric Bessin says “The dark mites are easily seen on the white pupae [(drones)] when the comb is broken or the pupae are pulled from their cells. ” He adds that it’s usually only easy to tell if they colony has been overwhelmed by the mites already.
The mites themselves are very tiny – the males never exceed 2 mm and the females are usually less than a single millimeter.
Hives already infected need to be separated from the rest of the apiary (bee “garden”). Researchers are still trying to figure out how to stop the mites. Pesticides worked effectively for awhile, but the mites became immune to them. There are various methods employed in killing the mites, ranging from freezing the drone larvae to coating the bees with powdered sugar so the mites fall off and can’t bite. A popularized, simple, and probably safe method is to use Apistan(R) by CentralApiary. The product is a sticky strip that contains chemicals for killing the bees. However, it may not be permitted in some states or outside of the U.S..
Some studies of interest include a study at West Virginia University and a very recent study by the Galtee Bee Breeding Group.
Comments on the WVU study
In 1996, a study was done at West Virginia University by Jim Amrine, Bob Noel, Harry Mallow, Terry Stasny, and Robert Skidmore on how to eliminate mites using essential oils. According to their findings, these oils (including patchouli, tea tree oil, wintergreen, etc. mixed into oil or grease) can kill the mites, and some just on contact, without harming the bees. Taking advantage of this in a hive initially led to disappointing results. The oils were fed to the bees at the entrance of their hive. The bees formed a syrup that they fed to their young, but the mites evaded the oils by “hiding” on the nurse-bees. However, a paper towel containing canola oil and wintergreen was placed where these bees gathered, and no mites were observed on the bees thereafter.
Comments on Galtee Bee Breeding Group
According to the Irish Times, the Galtee Bee Breeding Group studied grooming habits of bees and hopes that breeding bees with such habits will lead to better mite control. Support for this idea can come from the fact that, according to the article, “In the UK, scientists, using observational hives in which bees are individually numbered, have traced superior grooming behaviours to individual drone patrilines (male lineages) using DNA markers.”
These “superior grooming behaviours”, which the Galtee Bee Breeding Group hopes to harness, is an instinct in certain bees to bite and pull mites off of other bees. Furthermore, as the article adds, “other hives appear to exercise tighter hygiene controls, ridding the colony of varroa-infected larvae, which breaks the breeding cycle of the mite.”
My thoughts for a solution: Given the genetic engineering that we are doing these days – is there some way of either infecting the mites with a virus that kills them or “reprogramming” the mites (probably via DNA) to be beneficial for the bees? The main problem is the virus left behind by the mites; if this is eliminated, then the remaining problem is that the mite’s biting decreases the amount of blood in the bee, which, as Bessin says, can cause the bee to grow up without limbs (including wings).
What you can glean from this article at the very least: When the price of honey goes up at the store, you can blame mites.