Bt pollen and the little guys

[John Shuey]

Back in my old days, I worked at Battelle Memorial Institute, and a
co-worker looked at the Bt strain used to kill mosquitos and its impact on
predators.  Essentially the design was to infect mosquito larvae, then feed
the dead and dying larvae to a variety of aquatic predators.  The bottom
line was that there was no impact on the predators, either acute (mortality)
or short-term chronic (longer-term survival and growth rate).  This was
pretty much expected, given the mode of action and its specificity to insect
foreguts.

I'm guessing that the same studies have been performed for the lep strain of
Bt (the studies above were required by EPA) and that the data are out there.

John Shuey

viceroy at gate.net wrote:

> A friend of mine is carrying the flag in the battle for Butterflies
> Against Bt Corn.
> She is concerned, among other things, about the possibility of  genetic
> damage among the Monarchs that survive their childhood sublethal dose of
> Bt corn and survive to spread their tainted seed among the world's
> Monarch gatherings in Mexico.
> This seems to me a very unlikely problem, and I've suggested that she
> aim her big guns some provable problems. She suggested the food chain,
> not only the missing leps of all species, but the impact of Bt-flavored
> organisms on predators.
> She has heard, also, that the critters in the soil around the plant are
> also killed.
> Her feeling is that more research is needed, and I'm with her there.
> Is the bycatch going to be exclusively lepidoptera, or could predators
> be affected by eating poisoned prey?
> What about the genetics argument ... I don't see how it could hold
> water, but what do you folks think? If it's true of Bt pollen, it's true
> of all Bt spray, and we have a real problem.
> Thanks
> Anne Kilmer
> south Florida