When a colony swarms it leaves its old nest site, travels a bit and then has a rest. The scouts fly off and search out new sites. When the scouts return they perform a waggle dance to explain where the new site is. Other scouts go to the site to see for themselves and eventually the colony decides. There are some interesting features of this decision making. The queen is not involved, in fact most of the swarm is dozing and there is no strategic overview, no one bee visits all the available sites.