> Using our 5 survivor queens (all but one nice and strong) along with 2 other queens from local beekeepers, we requeened all the packages with virgins

Although we all want to breed better bees, and have been doing so for decades, there is a flaw in your methodology. Your sole criterion for selection is survival. Survival, especially in a harsh winter climate, depends on a large number of factors, including luck. Some colonies are better prepared, healthier, etc., but the notion that these traits can be passed on to survivors solely by introducing daughter queens from such colonies is simplistic. This would be like the survivors of a mass shooting expecting their offspring to be resistant to gunshots. 

Using selection to develop traits in honey bees is a difficult and painstaking task, which accounts for why so little progress has been made. I would look at what people like Danny Weaver and others have done. They have used huge populations and have incorporated a variety of lineages. They didn't sit back and watch 90% of their outfit die off, but used a portion of the bees to develop the resistant lines and built them up until they were sufficiently numerous to replace the susceptible lines. 

Also, one must not rule out factors that are passed from colony to colony by dividing; factors which are not genetic but relate to symbiotic organisms or so-called cultural mechanisms. The understanding of the transmission of epigenetic mechanisms is in its infancy, but there is a potential there to develop disease resistance and carry it forward to colonies in a non-genetic manner (eg., inoculation). Which would be a huge benefit, since the honeybees' system out out-crossing works against line breeding and if favor of the evolution of resistant populations. 

PLB

             ***********************************************
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

Guidelines for posting to BEE-L can be found at:
http://honeybeeworld.com/bee-l/guidelines.htm