Hi,

Used buckies, italians, and carnies at one time or another. Some colonies get more aggressive as they grow in population.  Sometimes they are cross due to the time of year and season and between flows.  Are you working with smoke? Be honest too? I f the colonies are extremely aggressive when using smoke then requeen.  Do the bees pour out by the 100's-1000's and start stinging before you get there? Or is it less than 30 or so after opening?  Is there  the scent of stings on gloves or clothing that would trigger them? Hmmmm.... helmet beating means they are warning you.  Do you have any critter signs around 2 or 4 legged?

As far as breeding usually using commerial bees on the first cross they can get a bit aggressive, but after open mating them for a season or two, one will dominate and they mellow right out to a happy medium.  At least for me they have.

Clay