Regarding your story about the bee deaths at Great Gonerby, as a lifetime beekeeper, who is currently operating around 175 hives of bees, I feel I am able to comment.
Looking at the photograph you published, the dead bees appear to be drones (male bees).
Drones are born during the spring and summer months; their sole purpose in life is to mate with new queens.
They do not forage and so are reliant on the worker bees to feed them.
At the end of the summer or in times of food scarcity the workers will evict the drones from the hives.
This is to preserve winter food reserves.
Evicted drones would normally die of starvation. It is quite normal to find dead drones at this time of year outside of hives.
There are other reasons why so many dead drones may be present.
It is possible that this colony in the chimney re-queened themselves earlier in the year and that the queen did not get mated due to the number of rainy days we’ve had this summer.
Queens mate on the wing (during flight) and need sunny days to fly within the first 30-40 days of their lives.
This is necessary to produce fertilized eggs – and only fertilized eggs will produce worker bees to ensure the survival of the colony.
If the queen should fail to get mated then this would make the queen lay infertile eggs which always produce drones, therefore increasing the ratio of drones to workers within the colony.
If this happens, the colony is doomed.
Bob Halsey, Colsterworth Honey Farm