Honey bees go to great lengths to maintain adequate temperatures for their colony. The consistency of their regulation is genuinely incredible. From heat regulation and fanning, just to name a few. Honey bees are masters at hive regulation.
This article will focus mainly on temperature control during warmer months, but they also use similar methods to control the humidity in their hives.
Research On The Subject
The work performed to keep temperatures consistent seems mainly for the benefit of the brood, which requires steady temperatures. One work noted that “While workers can survive temperatures up to 50 degrees Celsius (122 degrees Fahrenheit)(Coelho 1991), temperatures above 36 degrees Celsius (96.8 degrees Fahrenheit) for any appreciable length of time are harmful to brood and may result in developmental abnormalities or death (reviewed in Winston 1986)”.
One behavior is acting as a heat shield; perhaps you have seen in a hive when the brood frame is right next to the hive wall facing the sun, you will see a plethora of honey bees lined up against the hive wall. Perhaps you have wondered why that was. Due to the heat sensitivity of the brood, worker bees will change work tasks to what’s known as “heat shielding,” which will absorb the heat from the hive wall to protect the brood and keep them at optimal temperatures. (Heat Shielding: A Novel Method of Colonial Thermoregulation in Honey Bees)
Water also plays a crucial role in heat regulation.
When the brood nest is at risk of hyperthermia, water is evaporated by fanning bees to reduce the temperature of the hive (Ostwald et al. 2016). If fanning is insufficient, bees can increase evaporation by spreading droplets of water over brood cells and by performing back and forth extensions of the tongue while hanging over brood cells (referred to as “tongue lashing”)(Seeley 1995). (Supplying honey bees with waterers: a precautionary measure to reduce exposure to pesticides)
Fanning is a crucial behavior for honey bees to provide ventilation for the colony. To create airflow, honey bees will grip the comb and fan to move air through the entrance, and more honey bees will be stationed at the entrance to continue that airflow. If this was not fascinating enough, a study measuring the flapping frequencies and amplitudes of the honey bee’s wings showed that fanning has a different flapping frequency (the cycles the wings perform per second) and amplitude(the degrees the wings are tilted) than scenting or hovering. So the honey bees can change the way it flaps their wings to create better ventilation for the task at hand. The angle of the body of the fanning movement is different than scenting as well. Where scenting, they are pointing their abdomen at a higher angle up. (Wings as impellers: honey bees co-opt flight system to induce nest ventilation and disperse pheromones)
For survival, the honey bee colony has to keep the brood area at 35 degrees Celsius (or 95 degrees Fahrenheit). According to another work done in 1986 titled “Temperature Control in Honey Bee Colonies” it mentions “In warm environments, bees coll the colony to about 35 degrees Celsius (or 95 degrees Fahrenheit) by fanning their wings and by bringing water to evaporate within the hive. For example, bees have survived on a lava field where midday surface temperatures reach 70 degrees Celsius (or 158 degrees Fahrenheit) (Lindauer 1954).” (Temperature Control in Honey Bee Colonies)
The optimal temperature for a brood nest development is 89.6 degrees Fahrenheit to 96.8 degrees Fahrenheit (Selley and Heinrich 1981). They need to keep these temperatures year-round to keep the hive alive and in good health. The precision that they do this is just incredible.
These are just a few of honey bees’ behaviors and tactics to regulate temperature. Honey bees are masters of hive temperature regulation. They use water gathering and fanning in the warmer months to keep hive levels at optimal levels. The precision at how they do this is truly incredible – as temperatures outside fluctuate – inside the hive stays relatively steady.
The design of these creatures is truly unique.