With all the news about the impending cicada brood emerging this year, Brown Marmorated Stinkbugs, last fall's significant pest, may have been overlooked.
But for those who have noticed them crawling on the floors or walls, these bugs are beginning to wake up from their annual hibernation, according to Agriculture Research Scientist Don Weber, an entomologist who studies BMSBs in Beltsville.
"They are becoming active," said Weber. "What they're mostly doing in the warm weather is getting out [of their hibernating shelters] and finding food plants."
He said that scientists studying the bugs don't have firm population numbers, but said that adult bugs who managed to find proper shelter had a good shot at surviving the winter because temperatures weren't too severe.
"There were some rumors they were going to be a lot less abundant," said Weber. "It's pretty clear that's not true."
Historically BMSBs would hibernate in dead standing trees or on cliffs, but over time have adapted to civilization by making their way into homes in the fall, where they eventually emerge the next spring, according to Weber.
The bugs were first confirmed in Maryland in 2003, and are believed to have been brought to the United States from China as recently as the late 1990s, according to stopbmsb.org, a website set up by scientists studying the insects. Since then, their population has exploded, especially in the Mid-Atlantic region, causing significant harm to crops and resulting in the Department of Argiculture labeling them the top invasive insect of interest in the country.
Weber said stinkbugs emerging from hibernation are now feeding on trees, shrubs and other woody plants, but will eventually shift to fruits and vegetables once those begin to grow.
Weber is currently working with an aggregation pheremone that male stinkbugs give off to attract other stinkbugs to a feeding area. Scientists create the pheremone chemically in a lab, which is then used in traps to catch the bugs. Eventually, said Weber, the work may lead to a commercial trap available for farmers and possibly homeowners.
"By the end of this year, things will be pretty clear where the private sector can step in and serve various stakeholders like growers and homeowners," said Weber.
Currently, there are few options for homeowners inundated with stinkbugs, other than squishing or trapping the bugs, which aren't poisonous and don't bite, but do give off a cilantro-like smell when frightened.
Weber said through his research he has noticed that the bugs tend to congregate in outer suburbs, such as Howard County, where there is both abundant vegetation in the form of farmland and woods, as well as nearby housing.
"Inside the beltway, it's spotty," said Weber. "There's not that expansive number of host plants where they can build up their population."
Weber said scientists studying the bugs may have solid population numbers on them by the end of the year. A network of university entomologists in states where the stinkbugs are abundant estimated their population figures in 2012 using traps, but this year will be able to test the accuracy of those numbers with another year of estimates, according to Weber.
"We have an aggregation pheremone that is very effective during the growing season at attracting them," said Weber. "That will give us an idea of their numbers."
But will there be a great insect war between the now-ubiquitous stinkbugs and the emerging cicads?
"There's no interaction between the two," said Weber. "Other than people getting a little tired of both of them."
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