[Aliantha]

If he'd taken the cover off, the bees would have first become very aggravated and would have attacked. It would have been an invasion of their home. After the initial shock, the bees might have moved on, but more than likely the wouldn't move too far because for starters, they need emergency housing, so anywhere dry and out of the wind is going to be good. The cavities in the walls etc make a good spot, and a lot more troublesome than a BBQ to remove. That said, I agree that calling a bee keeper would have been the smart thing to do rather than poisoning them.