Peter de Bruyn Kops wrote:
> During the past decade in New Hampshire, we've seen major 
> winter losses (50-90%) on a 2-3 year cycle in operations 
> that run 50-200 colonies.  

That has been exactly my problem. I am in the Upper Peninsula of 
Michigan, and the cycle has been:

First year: Start with 3 or 4 nucs or packages (I've been using 
Carniolans, because they are reputed to be reasonably well-suited to our 
cold, wet climate with long winters).  They do well all summer, and all 
colonies overwinter successfully.

Second year: Make splits from overwintered hives, install new queens. 
All hives do well, with the overwintered parent colonies becoming very 
strong.  But, early in the winter the strong parent colonies die, 
leaving only the ones made from splits.

Third year: The overwintered splits initially do well, and additional 
splits are made from them to make up for the dead colonies.  But, then 
at the end of the summer, about half of them abruptly die over about a 2 
week period in late September.  The surviving colonies go into the 
winter OK at first, but then they dwindle down and die sometime in 
February and March.

I've been through this cycle three times now.  The first two times, I 
was treating for Varroa with Apistan, and this last cycle I was dusting 
them with powdered sugar every two weeks, and the treatment method 
didn't seem to make any difference.  The mites were there, and the 
quantities were increasing the whole time, so this was probably caused 
by them, but I just can't seem to keep them down.  I'm beginning to 
think that I'd go through exactly the same cycle if I didn't treat at 
all.   It's very frustrating, I can't even breed from survivors because 
the third year, nothing survives. I suppose I can just resign myself to 
starting over every third year, but it rankles. 

Can anyone suggest how I can cure this problem?  Please keep in mind the 
constraints of my climate:

(1) It never gets hot in the summer, peak temperatures are only about 
80F and that only lasts about a month (late July - early August), so 
mite treatments that require high summer temperatures are out.

(2) The period of time when bees can make honey only runs from about 
June 1 to September 1,  and their flight period only lasts from about 
mid-April to mid-October.  So, my window of opportunity for making 
splits is very short, and any mite treatment that has to be applied 
during the summer and contaminates honey for a period will basically 
mean that I never have a "clean" time to make honey for human 
consumption at all.

I realize that this has been gone over and over in the list for years, 
but the problem I have is that either (1) I can't sort out the 
successful people who have to meet the same climate constraints as I do, 
or (2) I can't tell whether someone who appears to be successful is 
actually just on the second year of their cycle, where it looks like 
everything is going just peachy..  The local beekeepers that I speak 
with all seem to have the same sort of problem.

Thanks for any advice, I hope that somebody has found a reliable way to 
beat the 3-year cycle in cold climates. 

-- 
Tim Eisele
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