Stink bugs are common insects that often become noticeable household pests, particularly as seasons change. Many people wonder about their activity patterns, especially regarding whether they are active at night. Understanding their behaviors clarifies why they are encountered at different times.
Stink Bug Activity Patterns
Stink bugs are not primarily nocturnal; they are diurnal, active during daylight hours. During the day, they engage in feeding and other natural behaviors. While they can be observed at night, this occasional activity does not categorize them as nocturnal. Their natural rhythm involves being active when the sun is out, which aligns with their feeding habits and environmental conditions. Stink bugs, especially the brown marmorated variety, respond to changing light and temperature cues. As daylight shortens and temperatures drop in the fall, they begin to seek shelter, often leading them towards human structures.
Why Stink Bugs Appear at Night
Despite being diurnal, stink bugs can frequently be seen at night due to several factors. A primary reason is their attraction to artificial light sources. Like many insects, stink bugs are drawn to porch lights, interior lights, and other illuminated areas, which can lead them directly to and even inside homes.
Another factor is their search for warmth and shelter, particularly as evening temperatures cool down. Stink bugs seek protected places to overwinter, and homes offer ideal conditions. They may aggregate on sun-warmed exterior walls of buildings during the day and then attempt to find entry points as temperatures drop at night. Once inside, the warmth of a heated home can cause them to become active, even during typical resting periods.
Common Daytime Behaviors
During the day, stink bugs are found outdoors, where they focus on feeding and reproduction. They are herbivorous, using their piercing-sucking mouthparts to extract fluids from plants. Their diet includes various plants, including fruits like apples, peaches, and berries, as well as vegetables like corn, tomatoes, peppers, and soybeans.
Stink bugs inhabit diverse environments, including gardens, orchards, agricultural fields, and natural wooded areas. In the warmer months, they are often seen on the sunny sides of structures or on plants, absorbing warmth before seeking sheltered locations as fall approaches.