What do bees do when it’s hot?

It’s really hot these past few days, you probably noticed. The bees are hot as well, and they don’t have any AC to use.
As I explained in my last email – the one about swarms – beehives are a super-organism, but what’s really interesting is that while individual bees are cold-blooded, the hive itself acts more as a warm-blooded super-organism.

Wait, what?

Yes, the hive acts as a warm-blooded organism. Cold blooded animals essentially revert to the temperature of their surroundings, becoming hotter or colder with their environment, while hot blooded animals, e.g. mammals, maintain their body temperature within a precise range of tolerated temperatures.
Just like that, beehives do the same. The brood chamber in the hive is very temperature sensitive, and the bees tend to keep it around 95F, regardless of whether the temperature outside is 30F or 90F. How do they do that?
The control the airflow through the hive, and use water evaporation for help. But when they have to, they can also reduce the amount of heat the hive is creating. How? By reducing the number of bees, essentially sending bees to “cool off” outside. Beekeepers call that “bearding,” as it looks as if the hive has a bee-beard outside it. Here’s a picture I took yesterday, you see three small hives (“nucs”). The middle one is facing away from the camera, but you can see bees from the closer and farther ones hanging around their “front porch.”

Enjoy your summer – until next time!