Agriculture Reference
In-Depth Information
opening nearest to the bee's head on the thorax. These openings are really air inlets that
allow air to enter the bee's blood stream. The mites enter this opening a few days after
the bee emerges when the hairs surrounding the opening are still soft.
Bees seem to vary in their susceptibility to this mite. In the USA, for example, it is
a major problem whereas, in Europe, it is a minor player and causes little damage.
This might not always have been the case, however. In the early years of the twentieth
century, the so-called Isle of Wight disease had a huge effect on British and European
beekeeping. During studies of this disease, the mite was discovered and immediately
blamed for every colony death. The mite may have been the culprit, or it may have been
part of the problem of vectoring viruses into the bees. Or the mite may have been there
all the time undiscovered when along came a new virus for it inadvertently to vector into
the bees. Suffice to say, every colony death at the time - whether caused by starvation or
something else - was blamed on this new mite. Diagnostic features and symptoms were
described and, of course, new remedies were sought.
The symptoms (which are still described in some texts today) include crawling at the
hive's entrance, crossed wings (K wing) and other wing troubles. These seem to me,
however, to be more likely to be associated with a viral disease. Treatments (which are
still touted) include 'Frow mixture' which was devised by a Lincolnshire beekeeper and
which consisted of nitrobenzine, saffrol and motor-car petrol. It seemed to work - or
at least it was used when the problem was passing, and Frow was rightly honoured for
his efforts. The thought of putting something like Frow mixture in a hive today would,
rightly, fill anyone with horror, yet some texts still advocate its use. Don't use it.
Identifying acarine
There are no certain field methods for determining an infestation. Dissecting the bee
and a microscopic examination of the trachea is the only way. There are no visible
symptoms.
Treating acarine
Certain evaporative treatments, such as those using menthol or formic acid and which
are used for varroa control, can be employed for the treatment of this mite, but it is best
