Very uncharacteristically, it has been hot in Seattle. Really hot. Nearly unheard of in June. Last year the high today was 68 degF, close to the 57-year average of 70 F. Today reached 92 F – and the bees noticed.
Bees work to maintain their hive around 95 degF. When it is cold, they generate heat by shivering. When it is warm, bees stand near the hive entrance, fanning their wings to increase air circulation. When it is hot, they ‘beard’.
Normally there are bees clustered at the landing pad of the hive entrance – bees landing, bees preparing to take flight, guard bees checking the credentials of returning bees. But during hot weather, there will be hundreds of bees clustered on the outside of the hive. They do this because even though they are ‘cold-blooded’, the movements, and even the mere presence, of their metabolizing bodies gives off heat. Multiply that by several couches of bees and it is what allows a hive to be 20 or more degrees warmer than the outside temperature.
In the Midwest, beards can be seen on hives even through the night. But in the Pacific Northwest, temperature drops quickly at night allowing our bees to go to bed in their snug hive after the sun sets.