>My impression is that Apivar (Amitraz) is a safer chemical than Apistan
(fluvalinate-tau) for bees, beekeeper and hive products, but I don't have
any conclusive data on this.  Maybe our researchers can comment.

"Safer" is a relative term.  And how the active ingredient is applied is an
important consideration.  Amitraz via Apivar has been shown to be much
safer to bees than amitraz via Taktic.  Of interest is the recent paper on
the response of the honey bee heart to amitraz
http://www.sciencedirect.com/science/article/pii/S0048357513001120.

The Penn State team found dead bees on the ground in a cornfield, with high
levels of amitraz in their bodies.  One would suspect that the source was
via the beekeeper using Taktic.  Liz Dahlgreen also found evidence
suggesting that amitraz may be rougher on queens than on workers.

Please do not get me wrong--Taktic has been used with great success by
commercial beekeepers for years, and Apivar is a vast improvement, and its
benefit:risk ratio to bee colonies is clearly positive.

But we simply do not yet know enough about these chemicals to fully answer
questions on "safety."

-- 
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