Wasps, a familiar sight during warmer months, exhibit a remarkable adaptation to survive the colder temperatures of winter. Unlike some insects that maintain colony activity year-round, most wasp species undergo a significant shift in their behavior and social structure as autumn progresses. This seasonal transition ensures the continuation of the species through the harshest period of the year.
Fate of the Colony
As winter approaches, the vast majority of a wasp colony does not survive. Worker wasps and male wasps, whose lifespan is typically only a few weeks, perish with the onset of colder temperatures and the scarcity of food sources. Their purpose is to support the queen and colony growth; once new queens are produced and mated, their life cycle concludes.
The declining temperatures also affect their physiology; below approximately 50-60°F, a wasp’s ability to fly and forage diminishes as its metabolism slows. While cold can directly contribute to their demise, starvation is a primary factor for workers and males. The old queen from the previous season’s colony also typically dies, having completed her reproductive cycle.
The Queen’s Winter Retreat
The survival of the wasp species hinges on the newly fertilized queen wasps, who are the sole members of the colony to endure the winter. These queens enter a state of dormancy known as diapause, which is similar to hibernation. During diapause, their metabolic rate significantly slows, allowing them to conserve energy and survive for months without food or water, relying on stored fat reserves.
To prepare for this period, queen wasps seek out sheltered and secluded locations offering protection from the cold and predators. Common overwintering spots include crevices under tree bark, hollow logs, and underground burrows. They may also find refuge in human-made structures such as attics, sheds, wall cavities, or unheated garages. Physiologically, some species produce glycerol, a natural “antifreeze,” to prevent ice crystal formation within their cells during freezing temperatures. Despite these adaptations, many queens do not survive the winter, succumbing to predators like spiders or dying if warmer spells cause them to emerge too early when food is still scarce.
The Deserted Nest
As the colony declines and new queens depart for their winter retreats, the physical wasp nest is abandoned. These papery structures, constructed from chewed wood pulp and saliva, are not reused by the queen or any new colonies in the subsequent spring. Wasps build new nests each year, a behavior that helps prevent the buildup of parasites and diseases from the previous season.
The old nests often deteriorate naturally over the winter due to weather conditions. Therefore, an empty wasp nest in winter indicates its inhabitants have either perished or the new queens have moved to their overwintering sites.