Nock,
Scouts are always keeping an eye out for good nest locations. As the hive preps for swarming, they increase their search. When the hive swarms the scouts are checking out every location that they can find and come back to the swarm and dance for the location they found. Then other scouts check it out as the scouts check out the different locations they dance for the best ones. If it is a so so location their dance shows that. If it is a great location the dance is much more vigorous.
When all of the scouts are dancing to the same location, the decision is made and the young bees are told to vibrate their wing muscles to warm up and within minutes the swarm takes off for the new location.
I was lucky enough to arrive at a very large swarm as it was taking off and walk with it for about a half mile. If you get a chance, do it.
As you are walking with the swarm, there are several thousand bees flying over your head at a normal walking speed. What was strange the first time was at eye level bees are flying at you at a very high speed. What is happening is these are the scouts who know where they are going and once they reach the front of the swarm they drop down below the young bees and fly at high speed to the back of the swarm. Once there they fly to the top of the swarm and fly at high speed in the direction of the new hive location. They do this horse track pattern above and below the swarm to direct the swarm. The entrance to the new hive is marked by the scouts using their nazenoff gland during their voting process and once in the area that is what the bees use to find the hive.
If you have scouts checking out your trap, watch them closely. When it looks like there are enough bees for it to be a good hive and they act real excited and sometimes even do a dance at the entrance, it usually means that that will bee their new home. Don?t be surprised if suddenly there are no bees at the trap. Keep checking the trap. They will be arriving soon depending on how far away the hive is and how far the queen can fly with out stopping. I have had them arrive in 30 minutes and I have had them wait until the next day.
Hope this helps.
Jim Altmiller