For some several years I have blamed poor queen performance on the use of
coumaphous for Varroa control.  Frankly, I had assumed that the drones were
compromised as they are produced in enlarged brood comb while queens are
principally produced in entirely new comb.  I was led to these conclusions
by a prominent queen breeder who shall remain unnamed.

Malcomb Sanford recently passed on the me the following summary of a
prominent researcher's study on the effects on queens.  (Why has this not
been reported in the magazines?  Could it possibly be because queen
producers are a major source of advertising?)  While I would term the queen
effects devestating, note that he concludes that the effects on drones are
probably more severe!

"Dr. Jeff Pettis, at the USDA bee lab in Beltsville, MD, conducted more
studies on the effects of coumaphos-contaminated comb on development and
longevity of honey bees. Queens reared in cell cups containing 100 ppm
coumaphos (the residue tolerance level set for beeswax by EPA) only had a
45% chance of emerging, and they were light weight. One queen made it from a
1,000 ppm cell, but she weighed only half of normal. If thy made it to the
mating nucs, queens reared with or without coumaphos had the same mating
success. Queen loss over six months was: control – 50% (inexplicably bad);
10 ppm – 45%; 100 ppm – 31%. Emergence of worker brood was: control –
95%; 100 ppm – 78%; 500 ppm – 60%; 1,000 ppm – 50%. Thirty to fifty of
each set of worker bees were confined to cages with sugar syrup for 21 days.
It appears that if they make it to adulthood, then their life spans are
similar: control – 21.0%; 100 ppm – 17.5%; 500 ppm – 18.0%; 1,000 ppm –
20.0%. Drones were not included in this study, but they appear to be the
caste of honey bees most susceptible to coumaphos."

Lloyd

-- 
Lloyd Spear
Owner Ross Rounds, Inc.
Manufacture of equipment for round comb honey sections,
Sundance Pollen Traps, and producer of Sundance custom labels.
Contact your dealer or www.RossRounds.com

******************************************************
* Full guidelines for BEE-L posting are at:          *
* http://www.honeybeeworld.com/bee-l/guidelines.htm  *
******************************************************