Second night in a row now I've caught them at this. Last night I smoked 'em back inside and looked around in there, but did not locate any trouble. We watched them all day today (feom outside) and saw only the usual coming and going. Now they're doing it again.... All over the front of my most active colony with a cluster haning down under the runway. A rookie wonders what they are up to.. and should I be concerned? Maybe it's the hot weather? Getting ready to swarm?