Re the subject of today's complaints of reduced queen longevity:

This is a subject of concern which I brought up in a recent article in ABJ
(Amitraz red flags).  Since my own operation has minimal exposure to ag
chemicals once I'm out of almonds, and no exposure to synthetic miticides
(other than from the wax coating on new foundation), I function as a sort
of "control group."

My rate of  loss of queens in their first year is in the very low single
digits.  Since I don't regularly track queens after that time, I can't say
how well they survive after that time, but have reason to suspect that
those whom I run for a second year continue to perform well.  This is
supported by observations by a friend who is a major queen producer, who
does color code his queens.

However, he does keep his bees in major ag areas, and does use amitraz as
his main mite control, and his combs still contain substantial residues of
fluvalinate, coumaphos, and fenpyroximate (legal synthetic varroacides).
Yet he still enjoys a low rate of queen loss (although not as low as mine).

The staggeringly high rate of queen loss suffered by some migratory
pollinators is of considerable interest.  The difficult thing is to
separate out the cause from the many variables.  There are a few
observations of note:

   1. Those operations suffering from rates of high queen losses often
   expose their colonies to a succession of pesticide exposures.  I strongly
   suspect that this could well be a factor in elevated queen losses, although
   it wouldn't necessarily point the finger toward neonics.
   2. But counter that with one poster's previous observation that there is
   minimal pesticide exposure to bees in Manhattan, yet he still reports an
   alarming increase in the rate of queen mortality.  This observation does
   not support the hypothesis that post-rearing exposure of queens to
   pesticides is the sole cause of elevated queen mortality (during-rearing
   exposure may be another story).
   3. Most migratory commercial pollination operations have a long history
   of applications of persistent lipophilic synthetic miticides, which may
   well exhibit synergistic effects with other residues).
   4. Their hives are trucked numerous times (I hear vastly different
   reports from other commercial beekeepers as to the rate of queen loss
   associated with each trucking event.  Some claim about 10%; others much
   lower).  One commercial beekeeper that I know removed the top hive clamps
   from his forklifts in order to force his employees to handle the hives more
   gently.
   5. Counter the above with the fact that my own colonies are generally
   moved several times a year without noticeable queen loss (no forklifts
   involved).
   6. Sandrock's (2014) results suggested that queens reared from stocks
   not previously exposed to ag insecticides may be far more susceptible to
   some sort of delayed mortality due to earlier exposure to neonics.  This
   finding is of great interest, and clearly needs to be replicated.
   7. On the other hand, I speak with many Canadian and Corn Belt
   beekeepers who place their hives in areas of the most extreme exposure to
   neonics applied by seed treatment, yet do not report excessively elevated
   rates of queen loss, despite their brutal winters.

I do not claim to have any answers.  But evidence that the observed
increased rate of queen mortality is tied to neonics is weak at best.
Evidence that it may be due to varroacide residues and other ag
insecticides is much stronger (Dr. Juliana Rangel has striking evidence
that exposure of developing queens to "normal" miticide concentrations in
the queen cell wax greatly reduces their future output of QMP, the
formation of retinues around them, and sperm viability in the spermatheca.

Dr Jeff Pettis has evidence that the chilling of queens during shipment may
greatly affect their longevity and/or sperm viability.

This is a subject of much concern to the commercial queen producers, who
typically try to avoid exposure to ag chemicals and persistent
varroacides.  Could this be a problem--that queen producers are rearing
queens in colonies that are not selected for resistance to common ag
insecticides?

These queen producers tell me that their queens perform very well in their
own operations; their ability to shake packages each spring supports this
claim.  They are frustrated by feedback from some operators who experience
early failure of entire batches of queens, whereas other shipments of
queens from the same batches do not experience such failures (one East
Coast researcher last year had nearly all of a batch of 250 Calif queens
fail immediately after introduction; the producer got no such reports from
other purchasers of the same batch).

This issue of premature failure of queens is of great interest, and queen
producers and researchers are trying to learn the reasons.  To date, there
is scant (although intriguing) evidence that it may be associated with
neonicotinoids (the subject of this thread).

-- 
Randy Oliver
Grass Valley, CA
www.ScientificBeekeeping.com

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