My experience is maybe 5% a year of my production hives go queenless.  I do not recall a single instance of a hive that was queenless in early spring out of several hundred I over wintered.  But, after swarm season I have occasionally had one go queenless.  I had one last year.  One three or four years ago.  I thought I had one this year as it was not building population but checked and found brood.  I think it likely that in the cases I have seen the hive swarmed as they were strong early on and somehow did not manage to requeen themselves. I can not call that a queen problem.   I get into my hives about March 15 or earlier if warm.  I want to install apivar strips as soon as the queen is laying so want to be early enough there is brood on only a couple of frames so I know where to put the strip.  I find one strip is enough when there is so little brood.  It is not uncommon to find a hive with zero brood.  Sometimes that queen does not start to lay for another three weeks. It would be easy to say that hive is queenless.  But, it is not queenless, she just is not laying yet.  I had hives go to mid April before some queens  started to lay one year with a wet cold spring bad enough they could not get pollen and were out of stored pollen.

I do not remember a single case of a healthy nuc going queenless in summer after having a laying queen even if they swarmed.  In both production hives and nucs I have seen many times that the queen was superseded.  Twice I found the old queen dead laying on the entrance board.  But the only other way I really know it happened was the old queen was marked and all of a sudden the queen has no mark.

I have seen rampant supersedure when a nuc is infested with EFB.  If untreated the nuc will go broodless before the new queen starts to lay.  Then the new queen lays and within a week the EFB is back and two or three weeks later the new queen is gone and the bees are raising a new queen.  I remember a couple that did that three times in under three months the first year I had EFB.  One of those ended up queenless the third time they superseded.  Then I treated with terra and the EFB promptly went away and I stopped having queens disappear.

When I raise queens I look at the cells at eight days and make sure they have food left.  No food and I pitch the cell.  I pay no attention at all to cell size as a few years ago I opened about 20 cells I thought looked small and found normal sized queen larva in most of them.  I put eight day cells in hair roller cages and emerge the queens in those cages in my cell builders.  That way I can look at the newly emerged queen and make sure she looks ok.  I find that about 10% fail to emerge and opening those cells shows all kinds of different failures ranging from death at a couple of days to death in the cocoon.  Once in a while I get one that looks hardly bigger than a worker and she gets pitched.  I mark them at that time which is easy for my shaky hands as they can not even fly yet.  Then I put them in a JZBZ queen cage and install in a just made nuc.  In 24 hours I direct release the queen into the nuc.  I  generally get about 90% mated ok.  But in about 10% the queen simply is absent.  If I installed 10 day cells my mating % would be about 80% due to those that do not emerge.  That sounds pretty normal from what I hear about mating % from others.

I really can not say I have a problem with queen loss.  I really do not know how long they live.  I know some last two years.  I even had an II queen last into her third year but she was in a nuc the whole time.  But, I nearly never go looking for a queen so only see them by accident most of the time.  If the brood looks good I am happy and think I know enough about her that seeing her tells me nothing.  If I get a production hive that is a bit hot I will look for her and pinch her and requeen by adding a whole nuc brood and all with a paper combine.  If it is a nuc I just rob them without mercy for resources to make cell builders or mating nucs until they are so weak I just take what is left 50 feet away and brush all the bees on the ground.  The queen disappears in that process but if I happen to see her I pinch her.  By not catching swarms and not breeding from hives that swarmed I do not have much swarming problems most years.  When I do have a hive swarm it is generally a nuc that is stacked up four or five 5 frame deep boxes tall and bees on top of the inner cover.  You crowd any hive bad enough and it will swarm.  Had two or three do that this spring.

I do live where pesticide exposure is pretty limited.  I personally use Round Up and trichlorpyr every year for weed control.  I spray my tomatoes with Captan to control blight.  There is one home within a half mile of me that has a lawn service so I suppose they get some pre emerge herbicide every spring.  I am across from an 800 acre park and I know they use some herbicides for weed control.  I am a  quarter mile from a major power transmission line and that right of way gets herbicides every year for brush control.  I suspect trichlorpyr from the look of the dying brush.  I also keep my bees in an unusual environment.  They are back in my woods surrounded by 50 foot tall trees.  They get a little direct sun in summer, but not a lot.  So, they do not suffer the mid day heat load a hive would experience out in the open.  I also live where pollen is available from late March until early November any day the bees can fly even in August when there is not a drop of nectar coming in.

Is it possible that some queen issues are just hives getting cooked in mid day to the point that the queen is damaged?  Or drones getting cooked in mid day and wrecking their sperm and then mating with a queen that ends up real short on sperm?  Particularly on a weaker hive that could be a issue I suppose.

Dick

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