Jerry Wallace <[log in to unmask]> wrote:
> You indicate brood viability is now around 98% since
> 2007.  I'm interested in what you did with your feral
> stock to improve the brood viability, if anything?  

Hello Jerry,

Looking back over the 10 years I have observed this problem, I believe the  poor viability I was experiencing was due to inbreeding and a lack of a sufficient feral breeding population.  I knew I would have difficulty effectively evaluating actual colony attributes until ferals needed for mating rebounded and viability improved.  So my program, since 1997 involved bringing in ferals from several county area to my assessment yard where I simply allowed them to cast swarms, while culling those under performing and moving some top performers into production.  When the feral population rebounded, I noticed much improved viability, better winter survival and increased productivity.

…I
> would expect hygienic stock to continue showing some spotty
> brood patterns unless they were vastly reducing the varroa
> load through other mechanisms.   I have some
> hives with Minnesota Hygienic queens which showed patterns
> with missed cells by late summer when varra levels got high.

Yes, I agree here.  I would expect to see some limited uncapping of worker cells starting during the time drone rearing beings to cease.  Prior to that, I expect worker cells not to show any signs of uncapping behavior, and varroa only infesting drone cells.  Consider the possibility that varroa are invading worker brood in late summer, not because levels are high, but perhaps because availability of drone brood becomes low.  Minnesota Hygienics are heavily weighted towards a singular mode of resistance, so I would expect uncapping to be more noticeable in this strain.  

If I may make comment on your statement  <<<I would expect hygienic stock to continue showing some spotty brood patterns >>>  I do promote hygienic behavior in my colonies.  But unlike the practice normally promoted by many on the lists, I believe it is not a good thing to depend on a single factor as a sole mode of resistance.  Therefore, colonies showing symptoms of removal of pupa, I interpret as a symptom which may indicate a lacking of  multifactor resistance.  Perhaps suggesting a deficit of resistant traits which preempt varroa prior to cell invasion.  IMO, selection of hygienic behavior is good, but if colonies show excess symptoms of uncapping, this indicates stress and I don’t like to see that.  Hygienic behavior is expensive to the colony, in that it involves the waste of resources used to rear the bee as well as the elimination of the future worker force.  Colonies having multifactor resistance would be more efficient in mite control and
 have the competitive advantage over colonies that rely on a singular mechanism of hygienic behavior which necessitates a sacrifice of resources to achieve the same resistance.

> Interestingly, the patterns of my old feral stocks and their
> vitality have improved with the addition of the new genetics
> to my main yard.  I suspect inbreeding was causing me
> more problems than I realized.

I agree!  IMO, I had sufficient resistance in my colonies to keep varroa at relatively low levels as far back as 2003, but the problem of lack of ferals which I depend on for breeding were adding an additional level of stress.  IMO, many are fooled into thinking varroa is the problem, when actually the effects of varroa are amplified because of the stress caused by low brood viability. 
 
> Did these hives survive the winter with no treatment? 
> If there were other underlying disease issues besides
> varroa, I would not expect them to survive based on my
> limited experiences with similar brood patterns. 

I do not treat my colonies.  In my experience, low brood viability was devastating for my wintering success.  Like others, I was fooled into thinking varroa was the problem, when in hind sight, it appeared to be low brood viability as the main culprit of winter mortality.  You can look at research by Page to read more on this.  

The very year I noticed more ferals appearing in my area, brood viability jumped to around 98% in many colonies, and I was rather surprised that even very small clusters which I normally combine prior to winter, or shake out in January now survive the winters in healthy condition.  

Were these
> queens used as breeders to improve your stock?

These were all ferals brought in from surrounding farmland and woodlands which I began during 2001 to focus trapping efforts on a 3 areas which I identified  as ‘early feral recovery areas’ where ferals were recovering the strongest, and ahead of other areas.

Best Wishes,
Joe


      

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