The brown marmorated stink bug (Halyomorpha halys) is an invasive species native to Asia that often concerns homeowners when encountered indoors during colder months. These pests seek shelter inside man-made structures, entering through small crevices in the fall to escape lethal outdoor temperatures and survive the winter. Once inside, they enter a state of suspended animation, raising the question of how long they can persist without the plant material they normally consume.
Survival Duration Without Food
The length of time a stink bug can survive without food depends entirely on its metabolic state. During the active feeding and reproductive season, an adult stink bug typically survives for about a week without sustenance. Under controlled, non-diapause laboratory conditions at warm temperatures (around 80°F or 27°C), adults have been observed to survive longer, with males lasting approximately 60 days and females up to 85 days without food. The crucial difference is the inactive state they enter for winter survival, which dramatically extends their longevity. This long-term survival is possible because they are not actively moving, feeding, or reproducing, effectively transforming them into low-power organisms that can persist for several months.
How Dormancy Extends Survival
The extended survival time is achieved through a specialized biological process known as diapause, which is an insect’s version of dormancy. This state is characterized by a drastic reduction in metabolic rate and a cessation of reproductive activity, allowing the stink bug to conserve energy reserves accumulated during the summer. To fuel this long period of inactivity, the bugs rely on stored nutrients, primarily lipids (fats) and carbohydrates like glycogen and sugars. Studies show a significant physiological cost during overwintering, with adults experiencing a 12 to 25% decline in lipid reserves and a depletion of carbohydrates by nearly half to three-quarters. The reduced metabolism also helps the insect limit water loss, which is a significant factor in long-term survival without external moisture.
Environmental Factors Influencing Lifespan
The duration of non-feeding survival is highly sensitive to the external environment, especially temperature. The primary purpose of seeking shelter indoors is to find a stable, cold environment that maintains the low metabolic state of diapause. If the bug is overwintering in a cold, unheated attic or wall void, its energy consumption remains minimal, allowing stored reserves to last for the maximum duration. Conversely, when a stink bug is in a warm, heated living space, this stable state is prematurely broken. Temperatures above 59°F (15°C) can trigger increased activity, causing the insect to burn its stored reserves much faster and shortening its overall survival time without food.
Hydration and Desiccation
Hydration is the second important factor, as the bugs still require some moisture, even in diapause. While diapausing individuals are highly effective at reducing water loss, extremely dry environments combined with warm temperatures are lethal. Such conditions increase the rate of desiccation, causing the insect to die from water loss much sooner than it would from starvation.
Post-Dormancy Behavior
The end of the overwintering period is typically triggered by rising temperatures and increasing day length in the spring. Once diapause is terminated, the stink bug becomes active again, and its immediate needs shift from survival to reproduction. The low remaining nutrient reserves mean that the insect must quickly find a source of water and food to survive and begin the reproductive cycle. This sudden demand for energy and moisture drives the bugs to move toward the light and heat, often bringing them out of wall voids and into the main living areas of the house. If they cannot find a way to exit the structure and locate host plants to feed on, the newly active insects will rapidly deplete their final reserves and perish.