As the days get shorter here in Massachusetts and the frost starts to settle on the landing boards, we tend to think about our hives in terms of equipment. Do they have enough ventilation? Is the entrance reducer on? Do they have enough honey stores?
But inside the hive, something far more miraculous is happening. The bees aren’t just changing their behavior; they are changing their very biology.
The bee you see foraging in July is physiologically different from the bee that survives a New England January. To understand how our girls make it through the freeze, we have to look under the exoskeleton.
The Myth of Hibernation
First, let’s bust the biggest myth: Honey bees do not hibernate.
Hibernation implies a dormant state where metabolic rates drop to near zero. Reptiles and some mammals do this. Honey bees, conversely, stay awake and active all winter. They are tropical insects living in a temperate climate, and they survive by creating their own micro-climate.
To achieve this, the colony shifts from “Summer Mode” (reproduction and collection) to “Winter Mode” (survival and thermoregulation). This shift requires a different kind of bee.
Enter the “Winter Bee” (The Diutinus)
In the spring and summer, a worker bee is built for speed and labor. She works herself to death in about 4 to 6 weeks. We call these “Summer Bees.”
However, starting in late summer/early autumn, as the pollen flow changes and the queen slows her egg-laying, the colony begins rearing Winter Bees (scientifically referred to as diutinus bees).
These bees need to live not for 6 weeks, but for 4 to 6 months. If a Summer Bee is a sprinter, a Winter Bee is an ultra-marathon runner. Here is the biological breakdown of the difference.
1. The Magic Molecule: Vitellogenin
The primary biological difference lies in a glycolipoprotein called Vitellogenin.
In Summer Bees, protein from pollen is converted into brood food (jelly) to feed larvae. But as the colony stops raising brood in the fall, the young bees stop exporting this protein. Instead, they sequester it in their own bodies.
Vitellogenin accumulates in the bees’ blood (hemolymph) and fat bodies. It acts as a fountain of youth:
- Immune System Booster: It protects cells from oxidative stress (aging).
- Internal Pantry: It serves as a dense nutritional reserve when honey stores are physically cold and hard to access.
- longevity: It suppresses the juvenile hormone that typically triggers bees to become foragers, keeping them in a “youthful” physiological state for months.
The Physics of the Cluster
Once the temperature drops below 57°F (14°C), the biology of the individual bee gives way to the biology of the “Superorganism.” They form the winter cluster.
This is not a pile of sleeping bees. It is a dynamic, heating engine.
- The Heater Bees: Bees in the center of the cluster disconnect their wings from their flight muscles. They then vibrate these muscles rapidly (shivering) to generate heat. They can raise their thoracic body temperature to over 100°F, even when it is freezing outside.
- The Insulating Mantle: The bees on the outer shell of the cluster pack together tightly, their heads tucked inward and their abdomen hairs interlaced. This creates an insulating layer that traps the heat generated by the core.
The cluster expands and contracts based on the ambient temperature. It moves upward through the hive body, consuming honey stores to fuel those shivering muscles.
The Long Wait
Right now, inside the hives at Harold’s Honey, thousands of these physiologically distinct sisters are vibrating in the dark. They are burning honey, sharing protein, and rotating from the cold edge of the cluster to the warm center, waiting for the first pollen of spring.
It’s a biological marvel, and it’s happening right in our backyards
