The survival strategy of bees in winter depends on the species. Solitary species typically enter a state of true dormancy or torpor, often as pupae or pre-mated queens. Social honeybees, however, remain active inside their nest and must fuel their collective survival until spring brings new forage.
Surviving the Cold: How Bees Stay Alive
Honeybees do not hibernate; instead, the entire colony survives by forming a dense, football-sized structure known as a winter cluster. This social strategy requires constant metabolic energy because the bees generate heat by rapidly vibrating their flight muscles. The core of this cluster is maintained at a temperature between 92 and 95 degrees Fahrenheit, even when outside temperatures drop below freezing.
The bees on the outer layer of the cluster serve as insulation, tightly packing their bodies to minimize heat loss. This constant need for warmth means the colony must continuously consume fuel to power their muscle activity. This contrasts sharply with solitary bees, which overwinter as fully formed adults inside a protective cocoon, relying on a drastically slowed metabolism to conserve the small food store left by their mother.
The Honeybee’s Stored Pantry
The primary diet for an active honeybee colony in winter is the food stored during the warmer months. Honey acts as the colony’s sole source of carbohydrates and fuel for heat generation. A healthy colony needs a substantial reserve, often consuming between 30 and 100 pounds of honey depending on the local climate and the length of the cold season.
The bees consume the honey, metabolizing it to power the muscle contractions needed to raise the cluster temperature. The cluster slowly migrates across the frames of the hive throughout the winter, following the honey stores to ensure a continuous fuel supply. A second, equally important component of the natural diet is “bee bread,” which is stored pollen fermented with nectar and glandular secretions.
Bee bread is a rich source of protein, lipids, vitamins, and minerals, initially consumed by winter bees to build up fat stores. Later in the season, as the queen begins to lay eggs, nurse bees consume the stored protein to produce royal jelly for developing larvae. This protein source is necessary for successful brood rearing before fresh pollen is available from early spring blooms.
Human Intervention: Feeding Managed Hives
Beekeepers provide supplemental feeding to ensure the colony has enough energy to survive when natural honey stores are low. During the fall, beekeepers may feed a thick sugar syrup, which the bees process and store as a carbohydrate reserve. This helps the bees build up their stores before cold weather prevents them from taking liquid feed.
Once sustained freezing temperatures set in, liquid feed is no longer an option because it can rapidly cool the cluster. Instead, emergency carbohydrate supplements are provided as a solid, such as fondant, candy boards, or dry granulated sugar placed directly above the cluster. This solid sugar provides an accessible energy source for the bees to consume without introducing excess moisture into the hive.
Pollen patties are usually reserved for late winter or early spring. This protein boost stimulates the queen to increase egg laying, helping build up the colony population in preparation for the upcoming foraging season. By providing these supplements, beekeepers aim to bridge the gap between depleted natural stores and the availability of new nectar and pollen.