Agriculture Reference
In-Depth Information
After decades of exposure and loss, most bees today are no longer terribly suscept-
ible to these mites. It is often questioned whether Mite-a-Thol or grease patties are even
necessary. Neither will leave a harmful residue in the colony, and both do an adequate
job of keeping any mite populations in check.
The grease patty is good insurance in the fall, when it is placed on the colony after
most brood rearing has ceased. It should be left on until the spring. There is little new
good data about this since no one is looking at this problem any longer. By using these
patties you are again selecting bees that are still susceptible to these mites and protect-
ing them. Ask what others in your area are doing.
The Russian lines and survivor bees are very tolerant to tracheal mites and they
should not have a problem with them at all. An uncommon strain of bee called
Buckfast
are highly resistant also.
Resistant bees; good management practices to reduce stress, diseases, and other
pests; and perhaps using grease patties in the fall should keep tracheal mite populations
in check.
Varroa Mites
In preparation for this revision, we surveyed several hundred people that had quit keep-
ing bees within three years of starting. One of the questions asked was, why had they
quit keeping bees? The overwhelming answer—more than 50 percent—was that varroa
mites had killed their bees two or more times, and they finally decided that this pest was
too difficult for them to deal with.
The second most popular reason was the trouble with colonies losing their
queens—two, sometimes more times in a season. These two problems receive a lot of
attention in this topic: They are serious enough to make enthusiastic beekeepers quit.
For this reason the following section is detailed and perhaps more lengthy than oth-
ers in this topic. But the importance of handling varroa mites in your colonies cannot be
stressed enough. I liken controlling varroa mites in beekeeping as important as knowing
which side of the road to stay on when learning to drive. If you don't control varroa,
your bees die, period.
Like tracheal mites, this pest is nearly universal, and like AFB, it is deadly without
beekeeper intervention. Unlike tracheal mites, however, this pest is large enough to see,
so detection isn't guesswork.
A fertile female varroa mite in your colony will seek out and find a cell with a larva
that is just ready to be covered by the nurse bees. She scoots down to the bottom of
the cell and hides there, in the remaining food and frass, until the cell is capped. Once
protected, she climbs onto the pupa, inserts her piercing mouthparts into the pupa and
