This paper is of interest, as it again appears to support the hypothesis
that exposure to neonics may affect queens.  But I'd be careful about
drawing conclusions until we see replication.

The reason is the small number of queens involved (statistically speaking),
which means that one must be careful about drawing conclusions from a
contingency table.  There did not appear to be any substantial difference
between queenrearing success, mating flights, or reproductive physiology.
The only apparent difference was in what we call "mate out"--the percent of
queens successfully laying fertile eggs after a few weeks.

In my area in good weather, I expect around 80% mate out of unchecked
cells, lower than that for introduced virgins (although some get great mate
out with virgins).  But that figure varies wildly, commonly from about 50%
to 95%.

In this study, ~50% of the neonic queens successfully mated out, compared
to ~79% of the controls.  These percentages are within normal variation,
thus calling for replication of this experiment before we run with the
results.

The other thing is that the exposure to neonics in this experiment was to
the cell builders, not the queens themselves.  I must strongly question
whether the developing queens were exposed to any neonic at all, since
nurses typically transmit very little pesticide residue through the jelly.

Of concern is the authors" interpretation in the discussion, in which they
state:

"Our study suggests that queen flights were not influenced by neonicotinoid
exposure because similar frequencies and lengths were observed compared to
controls. This was unexpected because neonicotinoids can negatively affect
worker bee flight behaviour."

Why would one expect any effect on flight or orientation at all?
Experiments to date that found problems with orientation were for bees
under the influence of neonics.  Since neonics are very rapidly degraded
metabolically, none of these queens could conceivably been "under the
influence," so would not be expected to show any orientation effect.

In any case, even if there was an effect on the queens, the question is
whether this could have anything to do with the apocryphal claim that we
are experiencing higher rates of queen losses these days.  If it were due
to neonics, that would mean that the Calif and Georgia cell builder
colonies were exposed to neonics during the cell building process.

I don't know about Georgia, but this certainly doesn't happen in
California.  So any purported elevated failure rate of Calif queens would
not be the result of neonics in the cell builders, even if they did have an
effect.

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

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