The Boxelder Bug (Boisea trivittata) is a common insect found across North America, recognized by its black body and distinctive red markings. These bugs are typically associated with box elder, maple, and ash trees, where they feed on seeds and leaves. The lifespan of the Boxelder Bug is heavily influenced by the changing seasons. Its total duration of life varies significantly depending on when it reaches the adult stage.
The Lifespan of an Adult Boxelder Bug
The active feeding and reproductive period for an adult Boxelder Bug is relatively short, lasting from a few weeks to a couple of months during the warm season. Adults emerging in the spring focus on mating and laying the first generation of eggs. These first-generation adults typically live only through the early summer.
The longest-living individuals reach adulthood in the late summer or early fall, as they must survive the winter. These insects enter a state of dormancy known as diapause, which extends their total lifespan to approximately one year in milder climates. Only fully developed adults can survive the cold winter months. The second generation of adults lives the longest because their active life is punctuated by this long period of hibernation.
Progression Through Nymph Stages
Boxelder Bugs undergo incomplete metamorphosis, passing through three distinct life stages: egg, nymph, and adult. Nymphs emerge from eggs laid in the spring, which hatch in about 10 to 14 days. The newly hatched nymphs are bright red and wingless, resembling miniature versions of the adults.
Nymphs progress through five distinct developmental stages, called instars, before reaching adulthood. During these instars, they shed their exoskeleton multiple times and gradually develop black markings and visible wing pads. This entire developmental period, from egg hatch to adult emergence, typically takes between 40 and 78 days. The duration is heavily dependent on warm temperatures and food availability, and the nymph stage usually lasts throughout the summer.
Seasonal Activity and Overwintering Behavior
The Boxelder Bug’s life cycle is closely integrated with the seasons, often resulting in one generation per year in cooler regions, or two to three generations in warmer climates. The first generation of nymphs matures into adults by midsummer. These new adults then mate to produce a second generation of eggs, and warm, dry summers often lead to higher populations.
As temperatures drop in the late summer and early fall, adults prepare for winter dormancy. This involves a migration away from their host trees to find suitable overwintering sites. They are often seen congregating on the sunny, south- or west-facing walls of buildings, attracted to the warmth.
The bugs seek shelter in dry places, sometimes flying as far as two miles to find a secure location to enter diapause. They gain entry into structures through small cracks, vents, and crevices, remaining hidden in wall voids or attics throughout the winter. The insects do not reproduce or feed during this hibernation period. They re-emerge in the spring when temperatures consistently rise, flying back to host trees to feed and begin the cycle anew.