From:
> http://www.aphis.usda.gov/plant_health/plant_pest_info/honey_bees/downloads/2011_National_Survey_Report.pdf
>

The pesticide results are on the last page.

I had a lot of difficulty with the pesticide residue graph because of the
chemical / metabolite names.  For one thing, I do not see chlorothalonil in
the list of fungicides, and I am not sure what metabolite might relate to
it.  The most common fungicide metabolite listed, THPI, seems to be from
captan from a limited search.  But I thought that on a previous years
report, which WAS discussed on the bee-l that chlorothalonil was the most
commonly detected fungicide, and it doesn't even appear on this list, so it
may now be under the name of one of its metabolites.  Anyone know?

As to the insecticides:
the 2,4 dimethylphenylformamide   is the metabolite of amitraz (beehive
miticide)
the fenpyroximate is from the beehive miticide HIVASTAN
the coumaphos and the fluvalinate are also beehive miticides
so is the thymol

So, lets leave them out for a moment (not because they are not a serious
problem, but because the discussion of them is a different one from
agricultural insecticides in the environment).  I think it is certainly
worth discussing them but we have discussed the development of varroa
resistant bees at length, and that is certainly part of getting rid of
these.   Also, the amounts of these has to be considered in relation to
their LD50 for bees.

So of the agricultural field insecticides found in the hive, only one
occurred in a higher number of samples than imidacloprid, and that was
chlorpyrifos.  But that one has a bee LD50 of 360 ng per bee and the
average detection in the positive was 6.5 ppb.

But for imidacloprid the  LD50 is 4 - 71 ng per bee and the average
detection in the positives was 30.8 ppb.

So it is clear that that neonicotinoid (it would now likely be
clothianidin) was the major field insecticide found in the beehives
surveyed in killing amounts.  And I think that is likely why Jeff Pettis,
one of the people who did this study, said in the Dan Rather news clip that
he thinks they have some part in bee decline.

And likely that is why we keep discussing it, Peter.

Also, Randy keeps pointing at canola as the poster child for hives
surviving neonics.  Consider this:  canola is a very good honey and  good
quality pollen crop.  There is lots of discussion of bees being starved in
modern agricultural systems.  So saying that well nourished bees can
survive neonics doesn't really exonerate neonics.  Really you have to
compare how bees do on untreated canola to how they do on treated canola
and I would like to see that experiment done on large acreage rather than
the little sample fields that the new Scott-Dupree experiment  is going to
do, so hive nutrition is part of the experiment. The problem is that there
is a lack of large acreages of untreated canola.  In my case, I look at
hives I put on treated canola and compare them with hives that do not go to
canola.   I don't see much difference.  But the hives that go to canola get
a high quality nectar and pollen source that blooms between clover and
goldenrod that the other hives do not get (the other hives are in a period
where not many other flowers are in bloom).  That is why I continue to go
to canola.  But the nutrition skews the comparison

Stan

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