The Beeinformed Partnership survey, and Bob's observation that commercial
beekeepers are having problems keeping colonies alive is of interest.
 Please allow me to share some actual data, rather than anecdotal reports,
or self-reported and unvalidated surveys.

Two winters ago, I was involved in a large trial involving about a dozen
commercial beekeepers from all over the U.S. who moved hives to almonds. We
graded the colonies for strength in fall, midwinter, and at the end of
January, prior to moving to almonds.  All colonies received the beekeepers'
normal management.  The majority had been exposed to agricultural forage.

We got a good data set for nearly 600 colonies.  Of those, only 14% graded
at less than 4 frame strength at the end of January.  If we were to count
actual winter losses, the number would be substantially lower, as many of
those colonies turned around and built back up.  Compare this low loss rate
with the USDA's self reported loss rate of 21.9%.

Of those 600 colonies, 200 were in my operation (little agricultural
exposure).  Of the 99 control colonies, which graded at 7 frames or better
in October, 89 (90%) were over 2.5 frames in late January.  In my area, 2.5
frame colonies at that time of year often rebound to become honey producers.

In my treatment group of 100 hives (treated with an experimental treatment
that targeted the paralytic viruses), 98 (98%) exceeded 2.5 frames strength
in January.  This result strongly suggests that those viruses were
associated with winter mortality.

This last winter, I ran a few additional trials.  In one of them I started
in late November with my weakest (and presumably sickest) 150 hives (I was
testing a product claiming to boost bee immunity).  I had to combine many
to even make 6-frame strength (all started between 6 and 7 frame strength
the first week of December).

I practiced standard husbandry, including December and January feeding of
sucrose syrup, oxalic dribble in fall, no nosema treatments, no synthetic
miticides since year 2000, minimal ag exposure.  95% of those colonies
survived and built up to be honey producers this spring (there was little
difference between the treated and control groups).

I don't know why my colonies exhibited such high survivability (which was
similar to the rest of my operation, but I have  actual data for this
group).  Good husbandry, low miticide residues, lack of ag exposure?  I'm
very curious about the latter two--the interaction between
beekeeper-applied miticides and ag chemicals.

The data from the Michiana beekeepers that I included in my article "What
happened to the bees this spring?" suggest that exposure to the ag
chemicals used in that area of the Corn Belt did not cause excessive
mortality.  This fact suggests that we look closely at the impact of
residues from beekeeper-applied synthetic miticides.

I've detailed the factors involved in this winter's high loss rate in the
above article.  I don't understand all the hoopla and finger pointing in
trying to solve the "mystery" of the high colony loss rate.  Plenty of good
beekeepers experience very low loss rates year after year (despite exposure
to seed-treated cropland).  Perhaps we should pay attention to their
practices.


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

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