Here I'm introducing a new queen to a colony that is weak because it's been without a queen for a little while. We need to judge their reaction to the new queen. Normally it's a clear attempt to feed her, or sting her (or try and ball up the cage and overheat her - another of their defensive mechanisms). Recently we've also observed the worker bees completely avoiding the cage the new queen is in. In this case they appear to accept her readily. She was successfully released and accepted into the colony (seen running around the frame and laying eggs). However, another couple of weeks later the queen simply disappeared. Sometimes they accept her, just long enough to make a new queen. But in the case of this colony they initially accepted new queens, but every time they disappeared a little while later. It could be they had been queenless for too long, so we eventually just united this (by now, very weak) colony onto an existing colony. Unfortunately we couldn't help this colony!!