When the last flowers of autumn fade and temperatures drop, the disappearance of bees from gardens and fields is a noticeable seasonal event. The answer to where these insects go depends entirely on the species of bee. Social insects, such as the honey bee, employ a collective strategy to survive the cold months, while solitary and semi-social native bees, like bumblebees and mason bees, rely on individual dormancy to make it through the winter. This fundamental difference in survival mechanisms determines where each type of bee spends the long period of scarcity.
Survival of the Honey Bee Colony
Honey bees are social insects that survive the winter as a complete colony inside their hive, rather than hibernating. When the air temperature falls below 57°F (14°C), worker bees form a tight mass known as a winter cluster to generate and conserve heat. This process is a state of sustained metabolic activity fueled by stored honey.
The cluster is highly organized to maximize warmth. The bees on the outer layer act as insulation, while the bees inside the core generate heat by vibrating their flight muscles, essentially shivering. The core is maintained around 80°F (27°C) when no brood is present. When the queen begins laying eggs in late winter, the bees must raise the core temperature to a steady 90–95°F (32–35°C) to keep the developing larvae warm.
Workers constantly rotate positions, moving from the cold exterior to the warm core, and vice-versa, to prevent freezing. During the coldest periods, the cluster contracts to conserve heat and slowly moves across the hive frames to reach new stores of honey. The colony drastically reduces or stops brood production entirely in late autumn to conserve the energy and food reserves needed for this extended warming effort.
Solitary Bee and Bumblebee Hibernation
The survival strategy of native bees sharply contrasts with the collective survival of the honey bee colony. Solitary bee species, such as mason bees and leafcutter bees, do not survive the winter as adults. Instead, they overwinter in a protected, dormant stage, spending the cold months as pre-pupae or adults sealed within individual cocoons or cells inside their natal nests.
These nests are typically found in sheltered locations, such as hollow plant stems, tunnels bored into wood, or small burrows dug into the soil. The developing bee relies on fat reserves accumulated before entering this dormant state, called diapause, and requires no external food stores. Survival depends on the protected location remaining stable, dry, and cold enough to prevent premature emergence.
Bumblebees employ a semi-social survival strategy where the entire colony dies off at the end of the season, except for the newly mated queen. This new queen seeks a sheltered location to hibernate alone, often digging a small chamber, called a hibernaculum, beneath loose soil or inside a rotting log. The queen relies on her own fat reserves to survive the six to nine months of deep rest before emerging in the spring to start a new colony. This individual hibernation is a true dormancy.
Essential Winter Resources
For honey bee colonies that remain active through the winter, the primary resource for survival is their stored food supply. Honey is the sole fuel source that powers the metabolic generation of heat within the winter cluster. Beekeepers generally ensure that a colony has a large reserve of honey, often around 60 to 90 pounds in colder climates, to sustain the continuous muscle vibration required to maintain cluster temperature.
The environmental conditions inside the hive also play a significant role in colony survival. Adequate ventilation is necessary to prevent the buildup of moisture, which is a byproduct of the bees’ metabolic activity. Moisture can be deadly if it condenses and wets the cluster. A dry hive interior is just as important as a full pantry for the colony’s successful overwintering.
Solitary Bee and Bumblebee Hibernation
The strategy of native bees is a sharp contrast to the social, collective survival of the honey bee colony. Solitary bee species, such as mason bees and leafcutter bees, do not survive the winter as adults; instead, they overwinter in a protected, dormant stage. These bees spend the cold months as pre-pupae or adults sealed within individual cocoons or cells inside their natal nests.
These nests are typically found in sheltered locations, such as hollow plant stems, tunnels bored into wood, or small burrows dug into the soil. The developing bee relies on fat reserves accumulated before entering this dormant state, called diapause, and does not require any external food stores from the previous season. The survival of these solitary individuals is dependent on their protected location remaining stable, dry, and cold enough to prevent premature emergence.
Bumblebees employ a different, semi-social survival strategy where the entire colony dies off at the end of the season, except for the newly mated queen. This new queen leaves her original nest and seeks out a sheltered location to hibernate alone, often digging a small chamber, called a hibernaculum, beneath loose soil, in a compost pile, or inside a rotting log. The queen relies on her own fat reserves to survive the six to nine months of deep rest before emerging in the spring to start a new colony by herself. This individual hibernation is a true dormancy, unlike the active winter survival of the honey bee colony.
Essential Winter Resources
For honey bee colonies that remain active through the winter, the primary resource for survival is their stored food supply. Honey is the sole fuel source that powers the metabolic generation of heat within the winter cluster. Beekeepers often ensure that a colony has a large reserve of honey, typically around 90 pounds in colder climates, to sustain the continuous muscle vibration required to maintain cluster temperature.
The environmental conditions inside the hive also play a significant role in colony survival. Adequate ventilation is necessary to prevent the buildup of moisture, which is a byproduct of the bees’ metabolic activity and can be deadly if it condenses and wets the cluster. A dry hive interior is just as important as a full pantry for the colony’s successful overwintering. These logistical needs for food and environmental control are paramount to supporting the honey bees’ unique strategy of active survival through the coldest months.