Yellow jackets are social wasps, known for their distinct black and yellow markings. Unlike some other insects, their colonies are annual, meaning they do not survive through the winter months. This seasonal life cycle dictates their activity and when they leave their nests.
The Yellow Jacket Annual Cycle
A yellow jacket colony begins in spring when a single, fertilized queen emerges from hibernation. She seeks a suitable nesting site, such as underground, in tree cavities, or human-made structures, and constructs a small paper nest from chewed plant fibers. She lays her first eggs, feeding the larvae until they emerge as sterile female workers.
By mid-summer, these first workers take over nest expansion, foraging for food, and caring for the queen and subsequent broods. The colony expands rapidly, reaching its peak size in late summer and early fall, often housing thousands of workers and a large nest with numerous cells. The queen remains inside, laying eggs, while workers support the growing population.
As fall approaches, the colony shifts focus to creating new reproductive individuals: males and new queens. These new queens build fat reserves for winter. After mating, which occurs outside the nest, male yellow jackets die. The original queen and all worker yellow jackets also perish with colder temperatures and dwindling food, marking the colony’s end.
Indications of Colony Decline
As the yellow jacket colony nears its end in late fall, several signs indicate its decline. Activity around the nest entrance decreases as temperatures drop. Cooler weather slows their metabolism, making them less active.
Individual yellow jackets may appear sluggish, disoriented, or be seen away from the nest, often resting on surfaces. These are workers nearing the end of their lifespan, struggling due to cold and food scarcity. Their foraging behavior may shift, as they become more desperate for sugary substances when insect prey becomes scarce.
The colony’s population dwindles as workers die off, reducing activity around the nest. The absence of sustained, aggressive activity around a nest, particularly after a few days of consistently cold weather (below 45°F), suggests the colony is dying off.
The Fate of Abandoned Nests
Once a yellow jacket colony has died out with cold weather, the nest structure is abandoned. New colonies do not reuse old nests. Each spring, a newly mated queen constructs an entirely new nest, even if a previous site is nearby.
The abandoned nest, made of a paper-like material, decomposes over winter. Its structure deteriorates rapidly due to moisture and freezing temperatures. While some nests might persist longer in sheltered, dry areas, they generally become unsuitable. Other insects or animals may take over parts of the abandoned nest for shelter, but yellow jackets will not return.