>To explain their differential sensitivity, we speculate that honey bees
are better pre-adapted than bumble bees to

> feed on nectars containing synthetic alkaloids, such as imidacloprid, by
> virtue of their ancestral adaptation
> to tropical nectars in which natural alkaloids are prevalent.
>

I've discussed this with Dr Cresswell.  Again, I do not wish to speak for
him, and have not asked for his permission to quote his correspondence.  My
understanding is that he has since pulled back from this explanation, and
now feels that the difference was because the bumblebees consumed far more
syrup per body weight than did the honey bees.

And yes, give free choice, bees tend to avoid high neonic residues in
nectar.

-- 
Randy Oliver
Grass Valley, CA
www.ScientificBeekeeping.com

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html