The varroa mite, or varroa destructor, has become one of the most troublesome pests of the honey bees in the last few decades.
A Short History
According to columbia.edu, varroa mites were carried to Hong Kong on imported honey bees (apis mellifera). They then spread around Asian countries as well as Europe and South America. "A single mite was discovered in Maryland in 1979; however, no more were seen in the U.S. until populations were discovered in Wisconsin and Florida in 1987".
Mites are parasitic, and can be compared to mosquitos. They transfer diseases between bees in a single colony, as well as between multiple colonies. The most destructive disease spread by the mites is called deformed wing virus (DWV). Mites are thought to contribute to Colony Collapse Disorder.
Mites in Our Colonies
Unless I were a beekeeper in Australia or Hawaii, it would be next to impossible to avoid mites in my hives. However, there are many known treatments that beekeepers can give their hives to help fight off the mites- everything from chemical treatments to natural treatments.
My dilemma: Should I use natural treatments that aren't proven to be effective, and risk my colony dying? Or should I use chemical treatments, possibly endangering the hive, but with high mite-killing success rates?
The two colony deaths this last beekeeping season were related to mites. It is my belief that Hive B died because the mite treatment that they were given possibly disrupted the queen's laying. It was too late in the season for the bees to recover, so they died from the low numbers. When Hive A was sugar dusted, the mite count was very low, so I decided not to treat. The mite count exploded in the next few weeks, overwhelming the bees and forcing them to abscond.
The image above shows a varroa mite on the abdomen of a worker bee.
The Image above shows deformed wing virus on a worker bee