>Not many commercial beekeepers keep meticulous records,

Only semi-commercial, but I do keep meticulous records.

Roger Patterson was quoted recently and I know that increasingly early queen failure has been a hobby-horse of his for some time.  I do not share his view from my experience and the current debate has led me to do a quick analysis (I am very short of time at the moment!) of 1466 queens from my records.
The data is shown below, with the year of birth, the sample size and the number of months that the queen lived.

Year	Sample	Lifespan
2005	27		18
2006	118		13
2007	127		14
2008	125		11
2009	145		12
2010	142		14
2011	134		9
2012	99		12
2013	88		17
2014	134		15
2015	96		13
2016	111		17
2017	81		18
2018	39		13

I was surprised at first that lifespans were not longer, but there are caveats.  All queens are recorded as soon as they start laying, so the data includes those that have failed to mate properly and do not produce viable worker brood.  If these were eliminated then the figures would improve.
We still have a number of queens alive that were born in 2016/17/18.  These have not been included in the data as they are still alive.  Their data will of course improve the figures when they eventually die.

I have not shown the spread of lifespans, but the max were 60 months.

The most important point for me is that there has been no deterioration in the lifespan from 2005 to the present and although Roger seems to discount the effect of the weather, the dip in 2011 was certainly due to it.  Colonies built rapidly, we split them, the weather went bad for weeks and many queens failed to mate properly and failing in the autumn.
It is said that many places in the world have climate, but the UK has weather!  Unpredictable weather at that - at the moment we are sweltering in an Indian Summer - but tomorrow will see change!!!

Best wishes

Peter 
52°14'44.44"N, 1°50'35"W

 

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