By Jim White, Associate Director, Land and Biodiversity
I like insects as much as the next guy — some might even say a bit more. However, there is one insect that I am getting a little tired of – the Brown Marmorated Stink Bug. I guess at first it was fun to see the little bugs scurrying purposely across my computer’s keyboard, when winter’s cold had forced the vast majority of other insects into an inactive state. But lately it has become a bit much. At least a hundred of these small triangular-shaped insects have invaded my office – crawling, and in some cases flying, around my work space. Finding them swimming in my coffee was disturbing but the last straw was when two of them looked to feeding on a Hershey’s Kiss that I left on my desk.
I decided to do a little research to find out more about these small, robotic intruders and to see if they can be controlled. Answers to the former were easy to find. However, answering the “how to get rid of” question remains the mostly unanswered.
The Brown Marmorated Stink Bug (Halyomorpha shalys) is in the insect order Hemiptera, or “true bugs”, and in family Pentatomidea. It is native to China, Japan, Korea, and Taiwan and has only recently been observed in the United States. The first record seems to have been in Allentown, Pennsylvania in 1996. Remarkably, in such a short time it has spread throughout the East and even has reported in Oregon. Although this insect does not bite of sting, it is considered a pest in its native range because it feeds on a wide variety of fruits and vegetables. The stink bug feeds by inserting its proboscis into a plant’s stem or fruit and then sucking out it’s meal. This typically does not kill the plant but does leave a scar, making the produce less desirable for sale. Therefor, the economic impact to Asian farmers can be considerable. Although this is a nuisance, they are not known to substantially harm our crops — yet. I have received reports from local gardeners that these insects have been found on squash and other home-grown vegetables and leave behind blemishes where they have fed.
Here in the U.S. it seems that the biggest problem is that the adult Brown Marmorated Stink Bugs seek out warm places in which to overwinter, resulting in their habit of invading homes and other buildings. They can be quite numerous in older structures and if sufficiently harrassed (squeezed or stepped on), will, like their name suggests, give off a strong, foul odor. The smell is a result of concentrated chemicals called aldehydes that are produced and expelled by the insect to ward off predators. Although not dangerous to humans, the chemicals can be toxic to some birds and other potential predators.
Back to the question of how to control these pests. It seems that the only effective way to keep the over-wintering adults out of buildings is to seal all openings to the outside; but that’s a lot easier said than done. And using chemical insecticides inside of buildings should always be limited (for human health reasons). So, collecting and disposing of the bug carcasses may be the only option. Time will tell if these invading creatures casue havoc in the U.S. other than just strealing a meal from my sweets supply.
Have you seen the Brown Marmorated Stink Bug in your house this winter?