Bearding is a term referring to bees accumulating at the front of the hive, in a beard-like shape. Bees do this to make room inside the hive for added ventilation on a hot and humid day. Both the temperature and humidity within the hive is kept to a precise percentage, for both the brood (they require temperatures 32-36C / 90-97F to form properly) and ambient humidity for nectar to be evaporated to honey.
Bearding bees can often be confused for a hive preparing to swarm, however, bearding bees look slightly different to a hive about to swarm.
Here are some differences between bearding bees and swarm preparations:
bees clustering at the front (both entrance/landing board and front panel) of the hive, in an attempt to make space inside the hive
it’s an exceptionally hot day
bees at the entrance facing in the same direction, fanning, trying to cool down the temperature of the hive
witnessed on days with higher humidity and heat– as temperatures drop in the late evening, bees should go back into the hive
congestion/lack of space in the brood box. Is your hive overcrowded?
a beard-like formation is accompanied by increased aerial activity in front of the hive (bearding bees crawl out of the hive without becoming airborne)
there are queen cells in your hive
Bearding is normal bee behavior. If you have concerns and feel unsure about whether your hive is simply bearding or preparing to swarm, we recommend getting in touch with a local beekeeping mentor, or beekeeping club/association/society, or ask the friendly Flow community forum.