What are common signs indicating that a bee colony may swarm?

The presence of queen cells and large drone brood are key indicators that a bee colony may swarm. Queen cells are specially constructed cells that a colony creates in preparation for raising new queens. When bees sense they are becoming crowded or their resources are ample, they may initiate the swarming process, which involves developing new queens. The presence of drone brood, which are the male bees, also plays a crucial role because drones are needed for mating with the new queens. In a colony preparing to swarm, you often see an increase in the number of drones being raised, as well as the specific formation of queen cells, which signal that the colony is preparing to reproduce by swarming. This combination of signs is a clear indication of a colony's intent to swarm.