Stink bugs, family Pentatomidae, are a large group of insects in the order Hemiptera distinguished by their piercing mouthparts and a large plate between the wings called a scutellum. There are nearly 5000 species of stink bug found across the globe, living in both tropical and temperature climates. Stink bugs are a very successful group, feeding on all kinds of plants and sometimes even becoming pests, because they have a set of amazing abilities that allow them to survive even in harsh conditions and new environments.
1. Chemical weaponry
Stink bugs are masters of chemical warfare. Those who have ever bothered one can testify that stink bugs will produce a pungent peppery odor, almost herbal, when threatened. This serves as an excellent deterrent for any would-be predator, which will get a mouthful of a strong and off-putting taste.
Some species of stink bug take this a step further by producing the deadly poison cyanide, making an odor similar to almonds. These stink bugs are quite toxic, sickening or even killing predators unlucky enough to consume them.
Not all stink bugs are toxic to humans, however, and some are even known as jumiles in Mexico and are consumed in tacos. They have a strong flavor, often described as resembling cinnamon mixed with iodine, and are said to be an acquired taste.
2. Aggregation pheromones
Stink bugs that live in temperate climates face serious difficulties when fall turns to winter. Freezing temperatures and snow will kill stink bugs, and even if temperatures do not dip that low food plants are often quite difficult to find.
Some species of stink bug cooperate, however, to survive the winter. They seek out warm locations and, upon finding one, begin to emit pheromones. These pheromones serve as a chemical lure that draws other stink bugs to the area, allowing large numbers to overwinter successfully. This can cause rather shocking numbers to congregate in homes and offices, often flying at lights and windows when the indoor temperature is high enough.
3. Piercing mouthparts
Stink bugs feed with tube-like piercing mouthparts, referred to as a stylet. Some species are predatory, using this stylet to pierce the exoskeleton of their insect prey, but the majority are herbivores. In fact, many stink bugs are serious agricultural pests due to their ability to use their piercing mouthparts to feed on soft plant tissue, often causing serious damage to important food crops.
4. Amazing reproductive ability
Some species of stink bug have become serious pests and can cause millions of dollars of crop damage. The Brown Marmorated Stink Bug, Halyomorpha halys, is perhaps the worst in this regard. Within two decades it spread across the entire US, from coast to coast, north into Canada. It can reproduce multiple times a year and can spread long distances by flying and hitchhiking in human vehicles, starting new infestations elsewhere. Read more about brown marmorated stink bugs in this article.
In order to protect themselves from predators that don’t mind the stink, the Pentatomidae have another trick up their sleeve. They have an extremely hard exoskeleton capable of withstanding the attacks of many other insects and even small birds. This exoskeleton is also very light, however, allowing for flight and thus allowing stink bugs to disperse and rapidly colonize new territory.