Buzz
Bees work tirelessly throughout their peak seasons—pollinating and ensuring that humanity avoids catastrophic downfall—so you might imagine that the cold months would prompt some kind of hibernation or restful retreat, even if it means succumbing to the winter's icy grip.
For bumblebees, this is generally the case. Struggling to withstand lower temperatures, large bee graves in northern climates are common, with only the queen finding refuge in a sheltered nook. But for honey bees, winter becomes a time to dig in and work even harder, pushing their survival efforts to the limit.
Their trick: they fly without ever actually moving their wings.
A single honey bee usually succumbs to exposure once temperatures drop to 28 degrees. To survive, a colony must literally huddle together, forming a communal furnace powered by their body heat. This heat is generated by the contraction of muscles in their thorax, which are responsible for flight. The wings stay still, but the resulting energy can elevate the bee's core temperature.
Transformed into miniature space heaters, the bees cluster together in a formation similar to a football huddle, with their heads touching and their abdomens (which are cooler) facing outward. The outermost layer endures a temperature of about 46 degrees, chilly but bearable. These bees form the protective shell or 'mantle' around the queen. Meanwhile, the bees at the center, insulated by layers of their fellow bees, enjoy a much warmer core, reaching up to 95 degrees.
Bees are also sensitive to shifts in their environment. If the temperature drops further, they can contract and raise their internal heat. On warmer days, they can relax and spread out a little. The outermost bees aren’t always stuck with the toughest job, either—they can often move into the warmer core, where they enjoy a cozy reprieve by the bee version of a fireplace.
Generally, the larger the cluster, the less work each individual bee needs to do to maintain the optimal temperature, increasing the colony's chances of survival. However, any cluster still requires energy, and if the honey stores are located too far away, leaving the group might result in death. The cluster will often move together in unison to access new honey supplies.
While honey bees are capable of adapting to cold temperatures, in modern times, their survival often depends on beekeeper intervention. In particularly cold areas, beekeepers insulate the colonies with a layer of fiberglass. They also make sure the bees' honey stores are well-stocked to provide enough fuel for the winter.
