Stink Bugs

You might not have heard of the brown marmorated stink bug, but chances are you'll see one soon enough. Honestly, I hadn't encountered this invasive pest either until 2015. While there are local varieties of stink bugs, the brown marmorated stink bug is native to Asia and has become a significant crop pest, wreaking havoc in agricultural settings. 

In their natural habitat, these pests follow a life cycle that produces one generation each year, supported by a variety of native predators that help manage their population. However, in 1998, the brown marmorated stink bug was discovered in the U.S., and by 2010, they were causing substantial crop damage to orchards, corn, and soybeans on the East Coast. In that year alone, they were responsible for over $37 million in losses to tree fruit in the mid-Atlantic region.

Aside from damaging crops, these stink bugs invade homes during the winter months, often in overwhelming numbers. For instance, in 2012, over 26,000 stink bugs were collected from a single Maryland home over 181 days. When stressed, they emit an unpleasant odor reminiscent of 'dirty socks.' 

Female brown marmorated stink bugs can lay up to 400 eggs in their lifetime. In more temperate areas of the southern U.S., these pests may produce up to six generations per year. Let's do the math: one fertile female, laying 400 eggs, assuming 50% mortality and half of them are male, multiplied by six generations—that results in a staggering 1 trillion stink bugs in one year! Essentially, that's about 143 stink bugs for every human being on the planet from just one pair in a single year.

Fortunately, there is a voracious predator that seems to have been accidentally imported alongside the brown marmorated stink bug: the samurai wasp. This tiny wasp is so small that it can fit inside the eggs of the stink bug. The female wasp lays her eggs in a clutch of stink bug eggs, and when they hatch, they consume the developing stink bug before it can emerge. In their native environment, these wasps are so effective they regularly eliminate half of the stink bug population, and in optimal years, they can eradicate up to 80%.

With any luck, this natural predator will help keep the brown marmorated stink bug at manageable levels. However, if they invade your neighborhood, it may be necessary to treat your home each year in early fall to significantly reduce the number of stink bugs that enter your living space during the winter.