Bearding is when bees make space inside the hive by dangling themselves off the outside of the hive, well, kind of like a beard. You may see anything from several dozen bees, to what may seem like your entire colony hanging off the hive.
This activity is normal, and is a colony’s way of regulating the temperature and humidity inside the hive – you may see your colony doing this when it is especially hot or humid.
If it seems that there are an excessive number of bees, you might like to conduct a brood inspection, as the colony may be very strong in numbers and need to be split.