Thank you David, for a request for fact, rather than opinion!

>My understanding is that the effects of Clothianidin is that it remains in
> the ecosystem and the hive for an extended time.


Neonics break down in about a year in sandy soil, but take several years in
heavy clay soils.  So buildup is clearly an issue in the latter.

>There seems to be more and more data to support the damages of low level
toxicity on the developing brood.

You are correct in this, and I am eager to see the publication of studies in
the works.  But the real test is always in the "real world," i.e., field or
tunnel studies.

>This is suspected to be one of the causes of the weakened immune systems
and increased virus loads in the adult bees.

Suspicions are a dime a dozen.  But, again, we should always *suspect* and
then test!  There is data indicating suppression of the immune system by
miticide contamination in combs.  Virtually any pesticide is going to cause
some sort of immune suppression.  I suggest that you review "High Levels of
Miticides and Agrochemicals in North American Apiaries: Implications for
Honey Bee Health," freely available on the web.  Look at the incidence of
various pesticides in the colonies, which would give you an idea which would
be most likely to cause widespread problems.

>All the information I have found says that only studies that pertain to the
direct mortality of the bees have been done.

Hardly, the EPA, and its counterparts in other countries require higher tier
testing, including field trials that measure colony development, production,
etc., which are the best overall indicator of pesticide effect.

 >Even then, the sample sizes have been small and the conditions of the
studies have been sloppy.

"Sloppy" is a word that might insult the researchers, who are generally
independent scientists.  Unfortunately, due to funding limitations, many of
the trials are smaller than I would like.  This is why I wish that
beekeepers could maintain a dialog with the pesticide companies.  I can tell
you that Bayer actively solicited beekeeper involvement is trial design, but
beekeepers did not pick up the ball and run with it, much to my dismay.

Randy Oliver

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