Descriptively-named, yet elusive in the description of its most striking feature, the Stink Bug has been invading America for a few decades. In New Jersey specifically, it was a good summer for stink bugs (or a bad summer for humans).
The stink bug is like a skunk but in bug form. I guess a skunk would be called a "stink rat" if it was also an invasive species. The bugs are a bit less problematic; they can only squirt 3 inches not 3 feet. Thing is, skunks don't get into your house. The bugs do, especially as winter nears and cold weather sends them seeking shelter inside your walls etc. In Spring, they reappear, this time trying to get back outside.
They don't bite, but they smell. But they only smell if they're threatened. Or if you squish them, releasing their obnoxious defense secretion. And what does that secretion smell like?
I'm paranoid, but for smells. When it comes to my own house, my place of work, or anywhere I have to spend a lot of time, I am constantly, actively smelling my surroundings. Noticing, investigating, researching, remembering. It started with a moldly basement apartment, but now I am hyper-aware of the entirety of my osmic environment.
Hype-aware, that is, except for the things I can't smell. I'm anosmic to putrescene (can't smell semen). You're anosmic to something too, probably. It's common. I once did an "experiment" in my workplace where I had an old smelly tube of paint; it smelled like rotten fish. Some of my coworkers couldn't smell it, and I thought it was strange, so I passed it around to everyone, about thirty people. Three of those people, the ones who didn't jerk their head away after sniffing, they were anosmic to trimethylamine, the smell of rotten fish.
What's more interesting is that one of those people was 50 years old, and he had no idea that he couldn't smell rotten fish. A whole life of smelling, and yet totally unaware of something like that. Around the same time I met a young man who was totally anosmic; he can't smell anything at all. He didn't realize it until he was ten years old, while playing a board game called P.U. The Guessing Game of Smells.
Back to stink bugs. I hear a lot about stink bugs, and being an odor aficionado, I find it hard to believe that I don't "know" what they smell like. (Granted I could settle this by ruthlessly smashing the next one I see, but I'm also so sensitive to smells that the thought of potentially dosing myself just sounds stupid.)
I ask people, lots of people, and you know what they say? They all say the exact same thing, "I don't know...it just smells bad."
I do some superficial searches: For a bug called the Stink Bug, you think there would be more descriptions of its stench. I need to contact an exterminator and ask them. Meanwhile, the best and really the only description is this list of slightly-related descriptors:
Strong herbs and spices
Intense-smelling herbs and spices
Rotten cilantro and coriander
The odor from the stink bug is due to trans-2-decenal and trans-2-octenal. The smell has been characterized as a "pungent odor that smells like coriander."
-Henderson 2006 below
trans-2-decenal descriptions from The Good Scents Company:
waxy, fatty, earthy, coriander, green, mushroom, sweet aldehydic with a chicken and pork fat nuance, diffusive orange odor with floral, rosey topnotes, citrus peel, citrus flavors especially orange and grapefruit, fruit flavors especially tropical, fried taste somewhat citrusy in dilution
trans-2-octenal descriptions from The Good Scents Company:
fresh, pungent, cucumber, spicy cucumber, green, leafy, herbal, vegetable, banana, waxy, oily, fatty, brothy, sweet, citrus peel, citrus especially orange, fatty notes of nuts especially hazelnut
Stink Bug Side View (pinterest = no copyright protection, good thing for watermarks? PBS)
Brown Marmorated Stink Bug - Halyomorpha halys
Green Stink Bug - Acrosternum hilare
Oct 2019, NJ.com
Detecting Stink Bugs/Damage in Cotton Utilizing a Portable Electronic Nose. Henderson, Will; Khalilian, Ahmad; Han, Young (July 9–12, 2006). Oregon Convention Center; Portland, Oregon: Clemson University. [PDF]
The stink bug is an invasive species in the United States. All the invasive species, plants or insects or whatever, seem to be from Asia. I think the real question here is this -- Do they have "invasive species" in Asia? Are our insects invasive to them? And how come I've never heard anyone ask this before?
Post Post Script:
By the way, the stink bug's natural predator? Samurai wasp.