On Tue, 7 Jul 2009 10:22:48 -0500, Bob Harrison  
<[log in to unmask]> wrote:

  > However the effect on the colony (other than the above) has been  
found to be very slight.

  Developing queens in colonies treated with as little as one  
coumaphos-impregnated strip for more than 24 h suffered a high  
mortality rate. Several of the queens showed sublethal effects from  
the coumaphos, including physical abnormalities and atypical behavior.  
The queens exposed to coumaphos weighed significantly less and had  
lower ovary weights than the control group queens. The highest  
coumaphos concentrations were observed in the queen cells and wax of  
the high-dose groups.

  Journal of Economic Entomology 95(1):28-35. 2002

  More recent information:

  The results of this study clearly show that coumaphos should not be  
used in colonies where drones are produced. Compared with controls and  
other miticide treatments sperm viability of drones exposed to  
coumaphos was significantly lower initially and continued the trend  
through the 6-wk sampling period. It is possible that extreme  
viability decreases observed in spermatozoa stored from coumaphos  
exposed drones could affect the performance of queens if mated with  
these drones. Queen performance could drastically decline 6 wk after  
insemination or mating, leading to queen failure, and thus partially  
explain the current problems associated with maintaining productive  
queens in colonies.

  J. Econ. Entomol. 101(4): 1081-1087. 2008

  [OK, so now I have a stack of papers on my desk that show that  
imidacloprid doesn't harm bees and another stack that show that  
miticides do. Yet some folks still insist that imid wipes out hives  
but miticides don't. The loss of queens 6 after six weeks or even six  
months, is not a trivial affair, unless you are getting them for free.  
What value is there in ponying up $20 or more for mite resistant  
stock, if they only last half a year and then get replaced with who- 
knows-what? You may not be using Checkmite but does your queen  
breeder? pb]

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