As the citation Pete gave to the Pettis article does not work in search engines here is an internet link:

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0147220

In the abstract Pettis says "Clearly low sperm viability is linked to colony performance and laboratory and field data provide evidence that temperature extremes are a potential causative factor."

When you look at the actual data many queens labeled as failing had sperm viability numbers very close to or even better than queens labeled good.  So, Pettis is correct, low sperm viability is LINKED to performance.  There is no way this paper proves low viability CAUSES poor performance.

I have limited experience with queens.  I have only grafted a few hundred and raised maybe 20 by splits.  I have only dealt with about 25 purchased queens two of which were II so really do not even count.  I have never raised queens from the ever popular swarm cells as I see no rational reason at all to selectively breed for more swarming which is what you are doing every time you use a swarm cell to make a new queen.  All in all really small numbers.

The purchased queens have been quite good for me.  I did buy one batch of five which were all duds.  Very poor egg layers from day one and the longest lived one of the bunch only made it to the following spring before supersedure.  The bees wanted to supersede one of the II queens from the second week I had her and managed it in Sept when I stopped killing supersedure cells.  The other II queen made it into her third summer.  Most of the rest of the purchased queens made it into their second or third summer.  Some headed big colonies and seemed to lay more eggs than others which headed smaller colonies.  I find the same variation in the queens I raise by grafting.  Some make big colonies and others simply never seem to build up big populations.  In all these queens I have had two drone layers.  Both happened in the same batch of grafts and did not lay until well over a month old.  Both laid 100% drone eggs fromd ay one as far as I could tell.  I have never had a queen that laid fertilized worker eggs turn into a drone layer.  In fact I do not remember ever seeing a single drone brood in a worker cell in a field of worker brood.  Such a drone brood would be quite obvious due to the cap standing higher than surrounding worker brood.  Just today I looked at a few thousand sealed worker cells for such a drone brood and could not find one.  I would think a queen that was failing due to either poor sperm viability or running out of sperm due to inadequate fertilization would produce such drone brood in worker cells surrounded by worker brood.  Even in that one batch of poor performing purchased queens I did not see such drone brood and it seems likely the problem with those queens was over heating during shipping.  After all, they came from the deep south in late June.  It seems to me that failing to see such drone brood argues that sperm viability is not such a big deal.  The eggs are getting fertilized.  As far as I know an egg can not get half fertilized and thus be a poor performing worker.  If I am wrong and poor sperm can result in partly fertilized eggs please show me some literature.

There are lots of things that can go wrong with a queen.  Temp extremes can harm her in many ways which could result in low egg production the rest of her life.  It obviously also can hurt sperm viability, but it is far from obvious to me that this is a major issue.  The real issue with poor performing queens is poor total egg production in my experience.

Dick

l

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