Well, time to eat crow :). Research so far was unable to show increased bee and larval mortality due to neonicotinoid exposure at field relevant doses. The latest study, “Field realistic doses of pesticide imidacloprid reduce bumblebee pollen foraging efficiency” published online in the current issue of the journal “Ecotoxicology,” shows that neonocotinoids actually impact pollen foraging.
I assume the impact on honey bees is similar to that on bumblebees. A hive exposed to neonocotinoids would collect less pollen and consequently raise less brood. Any beekeeper can see the effects: smallish clusters that succumb easily to pests and diseases and are not very successful at overwintering. The impact will look very much like a poor queen but it might be poor nutrition. Thoughts?
Original article here: Neonicotinoid Pesticides Harm Bees’ Foodgathering Ability