Brown Marmorated Stink Bug
Another new challenge seems to be on the horizon for pest control professionals in Wisconsin, as the invasive Brown Marmorated Stink Bug has established a breeding population and looks to expand to more areas of the state. According to UW-Madison and UW-Extension entomologist Christelle Guédot, scientists have confirmed that since their arrival around 2010, Brown Marmorated Stink Bugs have been recorded in eleven Wisconsin counties: Manitowoc, Winnebago, Brown, Outagamie, Rock, Dane, Jefferson, Milwaukee, Waukesha, Racine, and Kenosha. Unconfirmed sightings have also occurred in Polk and Ozaukee counties.
Originally from eastern Asia, these troublesome pests were first seen in North America eighteen years ago in Pennsylvania. Since then, they have expanded to forty-two other states and two Canadian provinces. According to Batzner Operations Manager and Associate Certified Entomologist Paul Matusiak, “2015 was the first year our Service Specialists really began seeing stink bugs during visits to clients.” Stink bugs are hardy, reproduce fast, have few if any natural predators in North America, which has helped them spread across the country and become a serious agricultural pest.
Physical and Behavioral Description
Adults are approximately a half inch long, with the typical stink bug “shield” shape, and marbled brown in color. They can be distinguished from other stink bugs by an alternating black and white color pattern on the margins of their abdomen, and by their dark-colored antennae with light-colored bands. Eggs are laid in clusters of 20-30 on the undersides of leaves. Brown Marmorated Stink Bugs will feed on the fruit, leaves, stems, and seeds of a wide variety of plants.
Why are they called stink bugs?
Stink bugs have developed a unique defense mechanism. When they are threatened or crush, they release a very foul odor. When stink bugs get inside homes, they can be so numerous this odor is often present and filters throughout the home. The scent is described as being much like the powerful smelling spice coriander. This is why removing stink bugs from the home via vacuum cleaners or by squishing them is not recommended. Handling the insects can cause them to release the odor and crushing them up does the same thing.
When their population is dense enough in a given area, they are capable of doing extensive damage to agricultural produce, edible garden vegetation, and ornamental plants. Similar to boxelder bugs, Brown Marmorated Stink Bugs seek shelter indoors as the weather begins to cool. This can be problematic for homeowners because, as their name suggests, these pests give off a foul odor when disturbed. To make matters worse, there is the possibility of an allergic reaction to the smell, and there have been reported cases of dermatitis when the insects are crushed against exposed skin.
If you do find one in your house, don’t be embarrassed. As Batzner Pest Control Training and Development Manager Steve Counsell explains, “Their name may sound like they seek out unclean environments, but these stink bugs are an agricultural pest and have nothing to do with sanitation!”
Prevention and Treatment
As mentioned, Brown Marmorated Stink Bugs will try to enter buildings to spend winter indoors. To prevent this, make sure that all potential entry points are sealed. Batzner can further help with this by treating cracks and crevices along the exterior, with extra attention given to areas around windows, doors, utility pipes, and other common entry points. An interior treatment can also be performed in active areas, focusing on cracks and crevices around baseboards.
While their populations aren’t big enough to cause much damage yet, these pests are definitely going to require a watchful eye and a dedicated response from companies like us to keep homes and businesses protected.