In a message dated 28/05/2008 02:16:34 GMT Standard Time,  
[log in to unmask] writes:

I’m  suspecting this aggressiveness is a result of 
crosses between domestic  strains, as history records much aggressiveness 
in bees during the time we  were replacing the German Black with the 
Italian and later, during the  early 1900’s Cyprian bees turned aggressive, 
but I’m not sure of any cause  to explain it.



Heterosis or hybrid vigour. Old men, now long dead, spoke to me in awe of  
the fearsome temper of the 'black Italians' around in the 1920s.  First  crosses 
often make a very cross cross but things calm down when all the bees in  the 
area are thoroughly mongrelised and normal selection for good temper is  
possible.
 
Then somebody decides the grass is greener with the latest fashionable  breed 
and introduces it to an area to the general detriment of temper.  I  was once 
persuaded to accept a NZ Italian queen - that stock was very prolific  and 
docile and handled and bred like flies and I made use of the prolific swarm  
cells they produced to re-queen other colonies.  It took me about 5 years  to get 
the temper of my bees back to as good as it had been before.
 
Chris (UK)



   

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