Thanks Stan for a most informative post, and you've awakened lots of
questions. I'd like to chat sometime, at your convenience.
You information fits what I remember about the presentation in Canada -
although I didn't remember that the symptoms looked like CCD, but rather like low
level chemical poisoning. However, you would know. One of the things I'd
like to talk about.
Bill Wilson and Stoner did some work many years ago with other pesticides,
long before the introduction of Imidacloprid and other nicotinics (which popped
on the scene in the mid-90s) They found that low levels of toxic chemicals
caused the bees to dwindle over a period of time. Eventually you got a
queen and young bees. Bill says they thought that since the queen was feed a
special diet, that maybe the bees feeding her more or less filtered out the
toxin or retained it in their own bodies.
Did your bees go down fast - days, couple weeks, or slowly - weeks, months?
Usually, low level poisoning takes some weeks, sometimes months to decimate
a colony -- but I've seen rather quick responses to toxic metals when a plume
hit the ground during an inversion.
Heavy metals generally dwindle down the population, and the brood looks like
it has foulbrood -- but the pathogen doesn't come up in the lab assays. Its
not foulbrood, but rather poisoned brood. The brood dies, and the adult
population is so decimated, the colony can't clean out the brood as fast as the
larvae and early pupae die. So, the brood rots -- smells just like
foulbrood, looks like foulbrood. Near the Tacoma smelter in the 80s, a local
beekeeper thought he had resistant foulbrood. His bees had enough arsenic, lead,
cadmium to kill them several times over.
My point, you don't have to pick out a specific category of poisons to get
some of these symptoms, many chemicals can produce symptoms that cause loss of
adult bees (as the chemical accumulates), and death of brood. Some take out
the brood first, if the dose is high enough.
I'm not saying Imidacloprid can't induce CCD - especially if CCD is a
response to multiple stressors. I'm just not convinced that the pattern of CCD
losses across all of the U.S. correlates with areas of Imidacloprid use - since
this chemical has been around for almost a decade.
I do think, seeing all of the soil samples from the potatoe fields -- that
bit about the clover initially through me, since I remembered potatoes-- that
the chance for external exposure to the bees in your situation was high - and
the study never assayed the critical end point -- the bees themselves. So,
you and I and everyone else has to guess as to whether Imidacloprid reached
toxic levels in your bees -- and we wouldn't have to invoke lost bees if that
were the case.
Thanks again for a factual report. That helps understand both your
situation, provides some hints. Most informative.
Jerry
The study may have collected bees, but I did not see/hear of any analysis of
bees. I did hear the same as you about levels in pollen and nectar, know it
was in the soils. I've seen analytical results from areas in U.S., also
showing retention in soils. Glad to hear that growers have gone to seed
treatments.
Maybe the CCD issue will be the key to getting the reports you want, and
that many of us would like to see.
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