WASHINGTON — They’re a pest well known to people who live in the D.C. area, especially when a person makes the choice to smash one, but this year homeowners may encounter fewer stink bugs.
“It’s a variety of factors we think that is seeing a decline in the stink bug population,” said Mike “The Bug Guy” Raupp, professor of entomology at the University of Maryland, College Park.
The first thing scientists are finding is that the natural enemies of stink bugs — insects such as the Chinese praying mantis and tiny parasitic wasps — are doing a number on the bug’s population.
Another factor is the polar vortices seen last year. Stink bugs do not do well in the cold, and Raupp said scientists have discovered that rapid cooldowns seen early in the winter season will diminish the chances that the bugs can survive the winter.
“Those cold temperatures may actually put a major beatdown on the stink bugs that are trying to overwinter,” Raupp said.
The final factor that has led to fewer of the smelly bugs is due in part to the warmer weather we have been seeing.
When a mother stink bug lays her eggs, a University of Maryland researcher found, she leaves a special residue on the eggs that the young bugs need to survive, Raupp said. The baby bugs consume that residue to get a bacteria needed for digestion into their guts.
“Once it hits to the 90s, that microbiome may actually be disabled or affected in a very negative way in the gut,” Raupp said.
That can prevent the offspring from surviving.