Brown Marmorated Stink Bug: Questions, Answers and Management Strategies for Homeowners

Learn how to bug-proof your home before brown marmorated stink bugs (BMSB) adults (Figure 1) decide to spend the winter with you after feasting on agricultural crops, ornamental trees and shrubs, and garden plants. BMSB is one of several insects that can make their way indoors in the fall in search of places to spend the winter. Others include the multi-coloured Asian ladybeetle (Figure 2), the boxelder bug (Figure 3), the western conifer seed bug (Figure 4), and on occasion, rough stink bugs (Figure 5). Most of these will end up in attics where they remain unnoticed, but some make their way into living spaces.

Figure 1 - Brown marmorated stink bug adult

Figure 1. Brown marmorated stink bug adult

Figure 2. Asian Ladybeetle

Figure 2. Asian Ladybeetle

Figure 3. Boxelder bug aggregation

Figure 3. Boxelder bug aggregation (Photo Credit: Whitney Cranshaw, Colorado State University,

Figure 4. Caption: Western conifer seed bug

Figure 4. Western conifer seed bug (Photo Credit: Gyorgy Csoka, Hungary Forest Research Institute,

Figure 5. Rough stink bugs are similar in size to BMSB but lack the two white bands on each antenna

Figure 5. Rough stink bugs are similar in size to BMSB but lack the two white bands on each antenna (Photo Credit: Steven Valley, Oregon Department of Agriculture,

Mechanical exclusion is the most effective way to prevent BMSB from entering structures. Seal all cracks, repair or replace damaged screens, and remove or cover window-mounted air conditioners prior to the fall. Live or dead stink bugs that have made their way indoors can be removed using a vacuum cleaner or shop vac (promptly dispose of vacuum bags or contents as the odour will persist).

Migration indoors usually begins in early September and ends by late October. In areas where BMSB is abundant, large numbers can sometimes be seen in the fall on the sunny sides of homes and other buildings.

Keep them out

The best way to avoid hosting these unwanted guests is to prevent them from entering buildings in the first place. BMSB will take advantage of any entry point, even very small ones that are not immediately obvious. Cracks around windows and doors, utility pipes, chimneys, exhaust fans and other openings should be sealed with silicone or silicone-latex caulk, expandable foam or weather stripping. Window air conditioners should be removed prior to the fall. Repair damaged screens on doors and windows. It may not be practical or feasible to seal all points of entry (soffits, air vents, space under metal roofs).

Should I spray for BMSB?

No. Insecticide sprays for managing BMSB indoors are not recommended.

BMSB can be removed or killed by crushing, freezing, or by drowning them in a small container of soapy water. If you are using a vacuum to collect individuals, be sure to use a bag-less type that can be cleaned to remove offensive odours. BMSB doesn't sting or bite, but it does produce a defensive odour or "stink" when handled or crushed. To avoid getting the "stink" on your hands, use a tissue or cloth to handle bugs.

Do BMSB sting or bite? Can they damage my home?

No. BMSB have mouthparts adapted to feeding on plants. They are not capable of stinging or biting people or pets, and they do not reproduce indoors. While they are a nuisance to building occupants, BMSB cannot cause structural damage.

Will BMSB breed indoors?

No. When BMSB come indoors to survive the winter, they enter a state of hibernation. During that time, they do not feed or reproduce. BMSB adults are not ready to mate and reproduce until the spring, after they move back outdoors and feed to build up their energy reserves.

Do other stink bugs overwinter indoors?

No. There are many native stink bug species in Ontario, but these bugs typically overwinter outdoors, under leaf litter and other protected natural spaces. BMSB's behaviour of moving into homes, sheds, barns, and other buildings is unusual among stink bugs.

Why should I care about BMSB?

BMSB is a serious agricultural pest capable of causing injury to crops and ornamental trees and shrubs. Feeding damage affects yield and marketability of commercial crops. At present, BMSB has been confirmed as established in the Hamilton / Burlington area and in Newboro, Ontario. Homeowner finds from other parts of the province indicate the pest may have a wider distribution; these finds are often the first indication BMSB is established in a new area. Help our survey efforts by reporting suspect BMSB.

What should I do if I find BMSB? Report it!

If you think you have found BMSB, either in your home or in your backyard, contact the Ontario Ministry of Agriculture and Food. Call the Agricultural Information Contact Centre at 1-877-424-1300, or email A physical specimen or high quality pictures are required for identification.

Report BMSB

Early detection is important to the long term success of management programs. We need to have a better understanding of where this pest is and how well it is established. There is a monitoring network for this pest; however, we have a better chance of finding pockets of small populations if more people are looking. Tracking the distribution and spread is essential. When BMSB is confirmed in a new location, this information can be added to distribution maps, providing growers in the area with an early warning system.

A sample or high quality pictures are required for identification. Pictures of BMSB and look-alikes can be found at If you think you have found BMSB, contact the Agriculture Information Contact Centre at 1-877-424-1300 or email, and we will provide you with instructions on what to do with the sample. To preserve the specimen, and to prevent it from becoming crushed or dried out, place it in a small container and freeze to kill it, or place it in rubbing alcohol or vinegar.

For the most recent distribution and abundance map (US and Canada) and for information developed by the Brown Marmorated Stink Bug Integrated Pest Management Working Group, visit

For more information:
Toll Free: 1-877-424-1300