Wasps are insects known for their distinct appearances, often featuring black and yellow patterns, and their role as both predators and pollinators in ecosystems. These insects can be broadly categorized into solitary and social species, with social wasps, such as yellowjackets and hornets, living in organized colonies. Many animals, including certain wasps, employ a survival strategy called dormancy to endure unfavorable environmental conditions. This temporary suspension of normal physiological activities helps organisms conserve energy during challenging periods.
Seasonal Cues for Dormancy
As autumn progresses, specific environmental changes signal to wasps that it is time to prepare for a period of inactivity. Decreasing temperatures and shortening daylight hours are the primary triggers for wasps to begin their dormant phase. Wasps typically become inactive once temperatures fall to within the range of 7°C to 10°C. As temperatures continue to drop, the existing wasp colony begins to decline, and new queens prepare for winter. The timing of this transition can vary depending on the specific wasp species and local environmental conditions.
The Dormant Wasp State
Dormancy for a wasp, specifically a fertilized queen wasp, involves a state known as diapause. During diapause, the queen’s metabolic rate slows significantly, reducing her energy consumption. This allows her to survive on stored fat reserves without requiring food or water. The queen wasp’s body undergoes changes, including the production of glycerol, a natural antifreeze, which prevents ice crystals from forming and damaging her cells. This state differs from true hibernation, but it serves a similar purpose, conserving energy until conditions become favorable again.
Where Wasps Hibernate
Fertilized queen wasps seek sheltered, undisturbed locations to overwinter during their dormant period. Common sites include crevices, under tree bark, and inside human-made structures. Attics, sheds, garages, wall voids, and roof eaves are frequently chosen spots due to their protection from extreme cold and predators. Hollow logs and soil cavities can also serve as suitable refuges. It is not uncommon for queen wasps to be found in crawl spaces or other quiet areas within homes.
Life Cycle Around Dormancy
The annual life cycle of a social wasp colony culminates with the preparation for dormancy. As autumn approaches, the existing colony begins to decline, and the worker wasps die off. The queen stops laying eggs for workers, focusing instead on producing new queens and males. These new queens and males emerge from the nest and mate. After mating, the newly fertilized queens disperse from the old nest to find suitable overwintering sites, while the males typically die.
When spring arrives and temperatures consistently rise, often above 10°C, the queen wasps emerge from their dormant state. Each queen then seeks a new location to build a small nest and lays her first batch of eggs, initiating a new colony for the year.