Boxelder Bugs: Accessible Ambassadors for Nature
by Jen Elison
Broadcast 11.17 & 11.20.2021

Photo by Archbob, public domain.




There I was, calmly taking a shower, when I realized I was not alone. Sitting on top of a bottle of shampoo waving its antennae and staring at me with its red eyes was a Boisea trivittata. Despite their scientific label, there is nothing trivial about these ubiquitous pests known to us by their common name: boxelder bugs. I wasn’t particularly alarmed by its presence in my bathroom because, like many people, I’ve become accustomed to finding them scuttling and flying around inside the house as the outside temperatures start to fall. It seems like every day since our first frost I have either been escorting boxelder bugs out of my house or running a gauntlet of them as I try to open my west-facing back door and duck inside without letting them swarm behind me en masse. I’ll admit to periodic frustration with boxelder boldness which has resulted in their death by flushing. I try to be more like my friend Linda, who names each boxelder bug she finds in her home and carefully releases it back outside. But it’s a challenge.

In my quest to be more tolerant, I set out to discover as much as I could about these bugs who seem determined to spend the winter inside. In case it has been a while since you have seen one, the body of the boxelder bug is half an inch long, oval-shaped, and dark brown to black in color, with wings lying flat against the body, forming an X. This X-winged formation indicates that they are part of the “true bug” or hemiptera order. They have six legs and two antennae, usually half as long as their bodies. I also learned that the scientific name, Boisea trivittata, refers not to them being trivial, but to the three red stripes behind their head. In fact, there are several red-orange markings on their backs, a clever way to warn off natural predators such as grasshoppers, rodents, chipmunks, and spiders. We should feel thankful that boxelder bugs are comfortable around humans—hence the large number of boxelder bugs that we see—because, when threatened, they can release a bad-tasting and smelly compound. And, if you look closely at a boxelder bug you can see four red eyes. Two are bulging and obvious, and two are smaller and located behind each of the main eyes. Entomologists are still debating the purpose of the smaller eyes, but they are thought to help the bug distinguish between light and dark.

The good news is that Boisea trivittata are basically harmless; they aren’t a type of bug that bites people. Their mouthparts are designed for sucking the juices of boxelder, maple, and ash tree leaves and developing seeds, but they don’t actually cause lasting harm to the trees. Once inside a building, boxelder bugs are short-term visitors, as they don’t live for more than a few days and they don’t reproduce indoors. They typically search for water when they come in so it’s not uncommon to find them in bathrooms, kitchens, and around houseplants. It seems the greatest trouble that they can cause, besides startling home dwellers by appearing seemingly out of nowhere, is that their excrement can sometimes leave a small brown stain on walls or windows.

It seems that I am not the only one on a mission to learn more about boxelder bugs. There are a variety of Citizen Scientist projects (SciStarter, Never Home Alone, and Questagame, for example) if you would like to be more involved in collecting data about these six-legged housemates. Chris Helzer, the Director of Science for the Nature Conservancy in Nebraska, is a true champion of boxelder bugs. He encourages us to take advantage of the opportunity that boxelder bugs provide as accessible ambassadors for nature. They are harmless, abundant, and readily available for study in our homes. Who could ask for a more convenient way to connect with nature? I think I’ll name my next boxelder visitor “Bob” before carefully releasing it back outdoors.


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