The annual autumn arrival of brown marmorated stink bugs (BMSB) into homes is a common and frustrating event as the insects seek warm, protected overwintering sites. Finding these shield-shaped pests crawling on walls or curtains often prompts the immediate, intuitive reaction to crush them. However, this action is highly counterproductive, directly answering the question: yes, squishing a stink bug can unintentionally attract more to the immediate area. The sharp, pungent odor released upon impact is not merely an unpleasant smell but a complex chemical warning signal meant to protect the insect and its nearby companions.
The Science Behind the Stink: Alarm Pheromones
The foul smell is a defensive mechanism, a noxious cocktail of volatile organic compounds released from glands located on the insect’s abdomen and thorax when the bug feels threatened or is physically harmed. This defensive secretion is chemically classified as an alarm pheromone, designed to signal danger to other stink bugs nearby. The two primary components of this pungent odor are the aldehydes trans-2-decenal and trans-2-octenal, along with other hydrocarbons like tridecane, which contribute to the distinct, sharp scent.
The sudden release of these chemicals serves to startle a predator and warn other bugs to disperse from the immediate threat. Brown marmorated stink bugs already communicate using aggregation pheromones. These aggregation signals are what draw the bugs together in large groups to safe overwintering locations like the walls of a house. When a bug is crushed, the alarm pheromone released can sometimes mix or be misinterpreted with the aggregation signal, inadvertently confirming to other incoming bugs that this is an established gathering spot. This chemical warning, intended to save the insect, instead becomes a beacon for more pests seeking shelter, drawing them toward the very spot the first one was killed.
Safe and Effective Immediate Removal Methods
Because crushing the insect is highly discouraged, immediate removal methods must prioritize capturing the bug without activating its defensive glands. One of the most effective, low-mess techniques is the simple soap and water trap, which uses a shallow pan filled with water and a few drops of liquid dish detergent. The soap is crucial because it breaks the surface tension of the water, preventing the bug from simply walking or flying away once it hits the surface, causing it to quickly drown.
Another highly actionable method is gentle vacuuming, which allows for the quiet removal of many bugs at once without crushing them. It is best to use a shop vacuum or a dedicated vacuum canister, as the residual odor can linger in the vacuum bag or filter for a period of time. A specific technique involves securing a knee-high stocking over the end of the vacuum tube with a rubber band, which traps the bugs before they reach the main canister. Once collected, the stocking can be sealed and immediately disposed of outdoors, or the bugs can be drowned in a bucket of soapy water. For individual bugs, a simple catch-and-release method using a tissue or a small, sealable container to gently scoop the pest is effective.
Long-Term Strategies for Stink Bug Exclusion
The most reliable way to manage a stink bug problem is to prevent them from entering the structure in the first place, focusing on exclusion before the insects seek warmth in the late summer and fall. Brown marmorated stink bugs can flatten their bodies to enter through openings as small as one-eighth of an inch, making a meticulous inspection of the home exterior necessary.
- Sealing visible cracks and crevices around window frames, door casings, and utility lines with a quality silicone or silicone-latex caulk is a high priority.
- Weatherstripping should be installed around all exterior doors and windows to eliminate gaps.
- Chimney flues should be covered with fine-mesh screening.
- Damaged or ill-fitting window and door screens must be repaired or replaced, as these are common entry points.
- Attention should also be paid to areas where air conditioning units or vents penetrate the wall, ensuring these openings are properly sealed.
Taking these proactive steps to eliminate structural vulnerabilities is the most practical long-term control measure against the seasonal invasion of these pests.