I cannot help you much with honeybees, or other insects, but I have been
involved in tracking reports and studies of the effects of toxins on fish
and amphibians, including neonicotinoid exposure. Most of this research
consists indeed of lab studies. The problem with field studies is that it is
hard to control the variables.
The other problem is that many of the studies are new, underfunded, take
time, and are in 'need to duplicate' mode.
That said, Yale's Environment 360 Jan 7, 2010 report seems to indicate that
we may be unwise to eliminate pesticides, and in particular neonicotinoids,
from our list of suspects in insects, amphibians, and bats. We just don't
know, but research suggests species may indeed be affected by
pesticides/herbicides (perhaps one toxin, perhaps combination, perhaps
combination toxins, climate 'change', and environmental stress) and that
some species may be heading toward a tipping point in their
survival/develpment.
I found the following exerpt particularly interesting, and it appears it is
indeed a field study. :)Andrea
But University of Padua entomologist Vincenzo Girolami believes he may have
discovered an unexpected mechanism by which neonicotinoids — despite their
novel mode of application — do in fact kill bees. In the spring,
The bat die-off ‘is the most precipitous wildlife decline in the past
century in North America.’
neonicotinoid-coated seeds are planted using seeding machines, which kick up
clouds of insecticide into the air. “The cloud is 20 meters wide, sometimes
50 meters, and the machines go up and down and up and down,” he says. “Bees
that cross the fields, making a trip every ten minutes, have a high
probability of encountering this cloud. If they make a trip every five
minutes, it is certain that they will encounter this cloud.”
And the result could be immediately devastating. In as-yet-unpublished
research, Girolami has found concentrations of insecticide in clouds above
seeding machines 1,000 times the dose lethal to bees. In the spring, when
the seed machines are working, says Girolami, “I think that 90 percent or
more of deaths of bees is due to direct pesticide poisoning.”
Girolami has also found lethal levels of neonicotinoids in other, unexpected
— and usually untested — places, such as the drops of liquid that treated
crops secrete along their leaf margins, which bees and other insects drink.
(The scientific community has yet to weigh in on Girolami’s new,
still-to-be-published research, but Pettis, who has heard of the work, calls
it “a good and plausible explanation.”)
--
"When the well runs dry, we learn the worth of water" - Benjamin Franklin
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