>> There is a very good reason to check for mites...people lack intellectual
>> curiosity, which I am sure you don't.
> well, i'm curious about a lot of things, but i have limited time and
> resources, as we all do. for the same reason beekeepers don't routinely
> test for the presence of "stress diseases" that are present in many (if
> not most) colonies, dwv for example, i'm not really concerned about
> whether there are mites in the hive, i'm concerned about survival...
PMFJI, but this topic is of real interest to me. I'll explain. I find
myself in the middle.
Having retired, my need to keep bees alive became less urgent and I became
fairly lax in my management, if you could call not looking at them more than
casually for a year or more, management. That year did prove something,
namely that all the work I had been doing as a commercial beekeeper had not
been unnecessary, since the majority died. I also discovered that the bees
I am keeping do not seem susceptible to AFB, since with the neglect and the
background level of spores, I should have had a wreck, and I saw no AFB.
Hmmm.
After a few years of retirement and ignoring my bees, I decided I need to
clean up all the odds and ends that are left over and do something with the
equipment on hand. I have enough to run 100 or more hives, so I started
splitting. Three became 10, 9 became 34. Now I am thinking more in terms
of a business again.
I really do not like drugs and pesticides -- I started out in the early
seventies thinking organic was the ideal -- but have always regarded them
as a necessary evil and always used them in accordance with IPM principles.
OTC was an exception. In fact, I eventually wrote a beekeeping (Green
Certificate) course that included a section on IPM. (Interesting how
writing a course deepens one's understanding).
IPM gets a bad rap from many who don't understand it. IPM is very
commonsense and emphasizes knowing the enemy and avoiding extreme positions
or extreme measures. Measurement and calculation are involved, as is
tolerance.
As a result, even as a commercial, I used minimal amounts and the least
nasty chemical that would achieve the required level of control, and in the
minimum amounts that would do so. (I never used coumaphos and hope I never
will).
IPM requires a method of monitoring, and I always preferred the least
destructive method. For varroa, natural mite drop worked fine for me. In
fact it still seems to do the job. I have been doing some 'experiments' and
the details are illustrated in my diary for any who suffer from insomnia and
need an instant cure. http://www.honeybeeworld.com/diary
As you said, different goals require differing approaches, and for those
looking for high survival rates and not minding using control measures --
management and chemical -- to ensure that result, monitoring is important,
as is knowing thresholds for economic damage to yards.
Those like yourself who do not care about high survival levels can actually
assist in reducing chemical inputs used by others by observing your hives
and reporting how high mite levels can go without apparent damage. I daily
meet beekeepers who want to see zero levels in their hives and are willing
to take measures to see that result. Is that really necessary or even
desirable? I think we all know it isn't.
Is there an equilebrium level at which point, some bees seem to gain control
and prevent further increase, or even reverse the growth? There seems to be
some evidence for this. Without observing hives which are untreated, no one
will know.
That brings me to the present. For years, I said that commercial beekeepers
need a service that monitors for mites and disease and perhaps even applies
the treatments, because that aspect of the business often gets relegated to
something that gets done after everything else, and requires a level of
expertise beyond what is somtimes available from the laborers in many
outfits.
It seems that pest management demands time in the periods when management
and labour available are stretched to the limit and working overtime
already, like right now.
In addition to focussing on this one important aspect and taking a load off,
such a service would have an overview of all the outfits in the area and
know if specific problems were local to the outfit, or general. With such
an overview, thresholds can more easily be established, since in a large
group, the effects of variations in methods can be assessed.
FWIW, we ran a small lab that checked for tracheal and nosema a few years
back as a sideline, but never pursued the project very far.
Guess what? Alberta Beekeepers and Alberta Ag set up such a service. The
service does not do treatment, but for a fee, beekeepers have an inspector
visit and take bee samples for varroa and nosema, with preliminary results
given for varroa on the spot. They also get a second opinion on problem
yards.
Over the years, I have worked as a bee inspector on many diverse projects:
disease, wintering, chalkbrood survey, etc... I haven't inspected for
years, but when a current inspector took some time off, I was asked to fill
in, and jumped at the opportunity. As a result over past weeks, I have been
looking inside an awful lot of hives scattered all over Southern Alberta,
speaking with the owners (who usually accompany me and pull the frames) and
making recommendations in accordance with the criteria set by our Provincial
Apiarist.
Naturally, I suddenly find myself thinking about my own hives in that
context, and becoming curious, so I decided to sample my own hives the way I
had been sampling the commercial outfits.
What am I finding? I am finding levels high enough that I would be
recommending treatment if speaking to a commercial operator. However, I
might add, that I have not found levels as high as the worst I have seen in
occasional yards of hives that have been treated in the last year. This is
not myy livelihood, so I tend to be more lax than I could recommend to
someone who makes a living from the bees. I drizzled oxalic last fall,
once. I may do it again, after all, I want my hives alive. Would I use
Apivar, as we recommend to the commercial operators? I really have not
decided. What do others think? I am reluctant.
> ... i'm having a hard time imagining any method who's predictions will
> correlate near 100% with the bond method. ... i can't imagine a method
> that can predict survival accurately.
It is true the correlation is not 100%, or even perhaps knowable, but there
are things that are known. For instance, a colony which goes above a 6%
mite count is very likely to have problems surviving. In Alberta, it has
been determined that yards showing levels over 3% are likely to present
management problems.
100% correlation is a lot to ask for in a non-destructive indicator. The
Bond method is quite destructive, counting mites is not -- not necessarily,
at least, although the gold standard, the alcohol wash, is to some extent.
But at least it does not kill the entire colony.
As you say, if you don't plan to act and only are looking for survival, then
knowing the levels is not useful. I am not sure what the point is then,
however, since most people keep bees for some useful purpose, yourself and
myself, excepted.
In my case, however, I have now decided that I do want to put the bees to
some use and propagate them, if only to fill up my equipment. As a result,
I will be acquiring queeens and cells from outside sources and be depending
on others who have been breeding stock with survivor and hygienic qualities.
Letting my bees die, therefore would serve no purpose.
To ramble on, I'll mention that in my travels, I am finding that progress is
being made in terms of eliminating suceptible stocks, even though some
commercial beekeepers are buying stock from everywhere they can. I visited
several large beekeepers who have stopped all AFB treatments for several
years and only find a few colonies (1/10 of 1% or less AFB annually). These
beekeepers are more discriminating in where they obtain their stock than
some, though.
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