The shield-shaped adult brown marmorated stink bugs (BMSB) are between ½ to ¾ inch long with grayish-brown speckling on the top and bottom. “Marmorated” refers to the light and dark bands along the edges of the body. Now (April – May) is the time that they emerge from their overwintering places in our houses to mate and lay eggs through the summer. Although the BMSB is not a threat to human health, people become alarmed when large numbers invade their homes (and even hotel rooms).
Did You Know…?
- Unwelcome, but not demanding: Indoors, BMSB do not form a nest, do not feed, do not reproduce and do not cause damage to the structure.
- Northward (or Eastward) Ho! The majority of insects will enter on the south or west facing side of a building, which are warmed by afternoon sunlight throughout the winter.
- Just pretend we’re not here: Once inside, they will hide in protected and dark places, such as wall voids, folds of curtains, and furniture.
- They stink! While they do not form health risk, they will give off an unpleasantly pungent smell if crushed.
- Build them out: This summer, seal cracks, crevices, corners, and other dark areas around windows and doors, gutters, flashing, etc. with a highly elastomeric sealant.
See The Unwelcome House Guest: Brown Marmorated Stink Bug —A Guide for Residents, Property Managers, and Pest Management Professionals fact sheet for more information on BMSB and how to manage them.