Why Do Stink Bugs Smell Bad?

Stink bugs produce a chemical that smells somewhere between cilantro or coriander and a skunk. When analyzed, the chemical contains compounds similar to what is found in the coriander plant.

This smell will not be too impressive from a single stink bug, but the chemical contains an aggregation pheromone that attracts others. One stink bug can attract hundreds to nest and hibernate. When this occurs, the accumulated smell becomes overwhelming.

Stink bugs store chemicals in their bodies, so when they are crushed, the chemicals are released. This makes treatment complicated because disturbing OR crushing stink bugs both result in the foul odor. When removing stink bugs, it is best to contain them to trap the odor they release.

Yes. In addition to defense, stink bugs release chemicals containing aggregation pheromones to communicate with each other. The message lets other stink bugs know there is a safe place to hide during winter.

This is important because stink bugs enter a hibernation phase called diapause when it gets cold. Once safely hidden, they slowly release this smell as a guide for others. This becomes problematic when hundreds or thousands gather in wall cavities or other hidden spaces.

No. Stink bugs control when they smell and what kind of smell to produce. There is a small difference between the chemical makeup of their defense odor and aggregation odor. Both are unpleasant to humans and hard to differentiate, but stink bugs can easily tell the difference. One is released when threatened; the other when safe and hidden.