>
> >New research proves pesticide link to CCD (??)


I have no idea how anyone could come up with the above extrapolation!

I find that the author did a good job in this paper, recognized "anomalous
data" such as Suchail's, and objectively analyzed existing research.  As to
his conclusions, read what the author actually says:

"Based on the fitted dose-response relationships, field-realistic doses of
imidacloprid had virtually no effect on rates of mortality in adult honey
bees in laboratory and semi-field conditions under either acute or chronic
dosing regimes (Fig. 1).  If this finding generalizes to environmentally
relevant field conditions, it suggests that the presence of trace dietary
neonicotinoids is not, in itself, the cause of catastrophic mortality of
adult honey bees, such as is associated with colony collapse disorder."

Bob partially quoted,
>From the conclusions:
"These findings raise renewed concern about the impact of the neonicotinoids
on honey bees that forage in agriculturally intensive landscapes"

But please allow me to then add the author's next sentences, which Bob
omitted:

"The meta-analysis suggests that the sublethal effects of field-realistic
doses of dietary imidacloprid are more pronounced under acute than chronic
regimes, which implies that single doses are more potent than multiple
doses, but this is probably an artifact, because the two underlying
meta-analyses draw data from both different subjects and responses.
Experiments with chronic dosing regimes, which permitted multiple
ingestions, used both colonies and individual bees as experimental subjects,
whereas experiments with actute, single dose regimes involved only
individual bees.  Colonies are likely to be more resilient to doing than
individuals when they contain uncontaminated food stores that bees consume
instead of dosed syrup."

Selective quoting does not help with our objective analysis of the effects
of neonics!

Let's put the author's conclusions into perspective.  He's clear that
"realistic" field doses would have virtually no effect on bee mortality, and
unlinks neonics from CCD.

As far as chronic doses affecting behavior, there is only a small apparent
effect at realistic field doses, provided that all the bees in the hive were
chronically dosed (this assumes that the studies were valid; I will critique
some of them in my article).  In real life, such dosing would only be likely
on a few crops, such as canola, sunflowers, and cotton.  In other crops,
bees normally forage on other sources (weeds), so will dilute the dose (I am
putting vine crops out of this analysis, as the levels of imidacloprid in
those crops can clearly occur at toxic doses, and I have concern about those
crops).

For canola, sunflowers, and cotton (some varieties of soybeans might be
included in this group), bees also generally find alternative sources for
dilution, too, but find the nectar of those crops attractive.  Of these
crops, the maximum doses to bee colonies would likely be from canola, since
bees actively work it for both nectar and pollen.  Yet under real-life field
conditions, colonies are able to put on large surpluses of canola honey,
which suggests that the behavioral effects of concern are of fairly small
measure.

As far as brood effects, the major neonic for seed treatments are now going
toward clothianidin and thiamethoxam, rather than imidacloprid.  These two
have virtually no toxicity on bee larvae (Lodesani, M, et al (2009) Effects
of coated maize seed on honey bees.
http://www.cra-api.it/online/immagini/Apenet_2009_eng.pdf).

So this meta-analysis fully supports the hypothesis that "field-realistic"
exposure of bees to neonicotinoids would have little effect upon bee
colonies at either the acute or chronic level.

I do not doubt Bob's observation that colonies are not thriving on intensive
agriculture.  What I do find little evidence for is that the problem is due
to neonicotinoids.  I suspect that other pesticides and poor nutrition are
to blame.

Randy Oliver

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html

Guidelines for posting to BEE-L can be found at:
http://honeybeeworld.com/bee-l/guidelines.htm