In brief
Wasps generally leave at the end of autumn when temperatures drop below 50°F (10°C). Most wasps die when temperatures reach 32°F (0°C)only the queen having survived until hibernate throughout the winter.
End of Wasp Season Timeline
- Late summer to early fall: Wasp colonies reach their maximum size and the queen produces new queens and males
- August to September: In North America, wasp season usually ends when the queen flies off with the males to create new queens.
- Below 50°F (10°C): Wasps become less active and it’s hard for me to fly
- End of autumn: Cooler temperatures stop the activity of wasp food sources
- 32°F (0°C) or less: Most wasps die because of famine and cold
Factors Affecting Decline in Wasp Activity
Temperature
- Cold weather: As temperatures drop, wasps become less active and their metabolism decreases
- Freeze: When temperatures drop below freezing with frost, most wasps begin to die
Food availability
- Reduced nectar sources: As flowers become scarce in late fall, wasps struggle to find sources of sugar
- Alternative food sources: Wasps can look for sugar in rotting fruit, picnic foods, and trash in late fall
Colony life cycle
- Queen hibernation: The queen wasp leaves the nest to hibernate for the winter, signaling the end of the colony
- Death of male wasp: Cold and lack of food kill male wasps
- Worker Wasp Lifespan: The average lifespan of a worker wasp is only 12 to 24 days
Changes in Wasp Behavior
- Increased aggression: In late summer and early fall, wasps become more aggressive due to the pheromones in their venom.
- Wider Foraging Range: As food sources decrease, wasps may range further from their nests in search of food
- Attraction to Sweet Foods: Wasps become more attracted to sweet foods as natural sources decrease
Environmental Factors Affecting Wasp Populations
- Climate Change: Warmer temperatures can cause early emergence, making wasps vulnerable to cold snaps
- Habitat Loss: Destruction of open grasslands or forests can cause wasp populations to decline
- Pesticide Use: Insecticides can have a significant impact on wasp populations and their food sources