If you see a stink bug, run!

Just kidding. Seriously. In all seriousness, stink bugs are harmless to humans. They just look like vicious, reptilian creatures. But they are actually no more of a threat to humans than the common housefly.

They have been likened to everything from dragons, to lizards, to dinosaurs. But they are, essentially nothing but plain old insects like any other, the one major difference being that they have a unique self-defense mechanism that no other insect has: They emit a putrid odor when they are frightened. This odor is enough to stave off just about any predator, and even human beings as well, keeping would-be predators at bay.

We have compiled a list of frequently asked questions concerning everything you never wanted to know about these pests and would never bother to ask:

Q. Why are stink bugs so creepy and annoying?

A. One of their distinguishing characteristics that makes them look so unique among other members of the insect world is their "reptilian" appearance. They look unmistakably like reptiles due to that "shell" like encasing on their backs, and its scaly looking texture. Adult bugs can grow to be as big as three quarters of an inch long, which compared to other common household bugs, is pretty huge. And their antennae can grow to be fairly long as well, thus contributing to their "creepy" factor.

Q. What's up with that cilantro-smell that they emit?

Located in the vicinity of the bug's abdomen are glands that emit an extremely pungent odor. This is their self-defense mechanism. Whenever they are threatened with any type of danger, they will release this odor into the air, as a deterrent against any types of predators. The stink is not known to be harmful to any other species, but it sure can be repugnant, enough to repel humans in disgust! And many people have compared the odor to that of cilantro.

And that is not just a sheer coincidence. As a matter of fact, the chemical that they release is a composition of trans-2-decenal and trans-2-octenal. The reason that the odor bears a resemblance to the smell of cilantro is because cilantro contains trans-2-decenal, the same chemical compound released by stink bugs.

Q. Do they harm human beings in any way?

Unless you count the psychological fear factor, they do not cause any harm to humans whatsoever. They do not bite. They do not suck your blood. They do not sting. All they do is cause many people fear, who happen to have phobias against insects. And they can cause humans to reel in disgust when they are sprayed with the stench. And as a matter of indirect impact on human lives, these bugs are known to be a threat to farms where crops of produce are grown and harvested.

Q. Do they have any predators?

If you are living in North America, you may be wondering where stink bugs stand in the food chain. Is there any other species that hunt or eat them? While there are predators that would love to get a taste of them, unfortunately they are not found predominantly in North America. This should come as no surprise, considering that these bugs themselves are not indigenous to this continent but are actually natives of Southeast Asia, particularly Japan, China, the Koreas, and Taiwan.

In China, their predominant predator is another insect known as the species Trissolcus halyomorphae, which is a member of the wasp family of insects. Interestingly enough, they are not predators of live stink bugs themselves, but actually will eat the eggs that they lay.

Believe it or not, the United States government is spending taxpayer money to study the stink bug epidemic in North America and is researching ways how to keep the population under control. This is not surprising, considering that these bugs pose an economic threat to the agricultural industry. The government is actually looking into the possibility of introducing these wasps into the North American ecosystem in an effort to combat the spread of their population. (Let's just hope that this doesn't backfire and inadvertently replace one epidemic with another!) The hope is that these wasps will eat stink bug eggs to prevent them from being born, thus establishing a form of natural population control.

Q. What do stink bugs eat?

Stink bugs are essentially herbivores. They eat mostly plant-based foods, along with some exceptions. Their diet consists mainly of plants, fruits, and vegetables. They consume their food by piercing it and then sucking up the juices. It is for this reason that stink bugs have proven to be a significant threat to farms where agricultural crops are grown. A swarm of these bugs will form a cluster and attack crops of fruits and vegetation en masse, leaving a swathe of devastation in their path, rendering the crops inedible and unsuitable for mass distribution.

Some Asian stink bugs will also feast upon caterpillars or the larvae of beetles, but for the most part they are herbivores.

Q. Why do these bugs want to come inside our homes?

Unlike many insects who might simply go into hibernation during the onset of the cold winter months, this species of bugs are unique in that they will actively seek out warm places to go and take up domicile so that they can continue to stay active. When they happen to fly by the vicinity of your home, they may pick up on the heat that is emanating from inside. Therefore, these little buggers will try to gain entry into the confines of your home, in search of that warmth, by any means necessary.

If they can find a crack in your foundation, they will slip through it. If they find a crack in your window sill or a gap in between where the window or the door meets the walls, it will manage to squeeze through it. If you have a window-mounted air conditioner unit, it will easily gain entry into your home. If it locates the chimney or any of the various exhaust vents that lead to the exterior of your home, they may make their way through there to get indoors.

And once they get indoors, they will find places to hide out for the winter. One thing that is noteworthy about them is that they will tend to flock toward the exterior windows of the house during broad daylight, because they also seek out sources of light, in addition to heat.

Q: Why are stink bugs frequently seen in clusters?

A: Once one of them gains entry into your house or into a particular area within your house, it will release a special type of pheromone, known as an aggregation pheromone, into the air that is designed to attract others. This signals other stink bugs to come hither, and that this area has been identified as being safe and hospitable to the original one. Therefore, others will follow the scent and will come and join the first one.

Q: If you kill one stink bug, will others follow the stench that was released just before it died, and come to that area? Do they get attracted to their own stench?

No. This is a rumor that has been proven to be untrue. Stink bugs will not be attracted to others who have just been killed in a certain place. However, as stated in the previous question, they will come to a place where the first one will have released its aggregation pheromone.

Q. How did these bugs come to North America?

Stink bugs are illegal aliens in our land. Much like the stowaways of the colonial era who would sneak aboard ships to come to The New World from Europe, they managed to become stowaways and were brought here to North America on cargo ships. (The only difference between a human stowaway and a stink bug is that the former came here intentionally and the latter came here by accident.)

The most commonly held theory of how and when stink bugs first arrived in North America is that at some point in the late 1990s, a cluster of them inadvertently got trapped into a shipping crate aboard a cargo ship as it left the seaport of either Japan, China, the Koreas, or Taiwan. If the cargo was supposed to have been inspected prior to departure, these stink bugs apparently managed to slip through the cracks (pun intended) unnoticed.

The first report of stink bugs being sighted in North America was in Allentown, Pennsylvania in the United States, in the year 1998.

And now, nearly a decade and a half later, they have spread to over 30 of the lower 48 states in the continental USA.

Q. What kind of climate do stink bugs prefer?

Since these bugs are native to Southeast Asia, predominantly centered around China, Japan, the Koreas, and Taiwan, it follows that the climate that they prefer would be that which bears the most similarity to these regions. So it can be expected they will naturally seek the means to gravitate toward those population centers within the North American continent that bear the most resemblance to the climate of the native habitat.

Q. Are there any ways to kill them without smashing them?

There are many ways how to kill stink bugs without smashing them, which in turn releases that pungent odor of theirs. Check out this section of the website, for practical tips on how to kill them.

Q. Where else can stink bugs be found in the world?

As of right now, they are centered primarily around southeastern Asia, localized to Japan, China, Taiwan, and the Koreas. In the past decade, they have now become widespread in North America.

Q. How long do stink bugs live for?

The lifespan of a typical stink bug varies, depending on their exposure to the climate. Those that are unable to seek shelter during the winter will no doubt perish sooner than those that are able to hibernate or find shelter indoors. But typically, the longest one can live is about 6 to 8 months.

Q. How do stink bugs mate and reproduce?

As with any other type of insect, stink bugs lay eggs. What is interesting is that their eggs are actually subject to attack by predators such as wasps who seek to eat them. Scientists are actually looking into the possibility of introducing wasps into their habitat as a means of population control in highly infested areas where reproduction is most likely to take place.

Q. Why do stink bugs have that reptilian look? What's with that armored plate?

The armored plate on their back is, in fact, a shield. It serves as the bug's exoskeleton (a skeleton that is on the outside of the body, unlike mammals whose skeleton is on the inside). This shield is strong enough to repel insecticides, so if you have ever tried to spray a stink bug with dish soap or with bug spray, you might notice that it has no effect on it. If you want your spraying to have any impact, then it is important that you aim for the underbelly.

Q. What happens to them in the winter?

Stink bugs cannot survive the cold, harsh winter climate. Therefore, as a matter of instinct, they will look for warm places to retreat to during the winter. Those who happen to discover homes or any other buildings where warmth is emanating from, will attempt to gain entry through cracks and crevices. Once inside, they will either hibernate if it still too cool for them to subsist, or if it is warm inside, they may end up remaining active for the winter.

Those that remain outdoors will attempt to find a safe place to hibernate among the leaves of trees.