Even though they’re small, bed bugs can be one of the most unsettling things to find in your home. But surprisingly, what do these little bloodsuckers tend to avoid? Recent research suggests that water is their biggest nemesis.
A team of scientists from the University of California, Riverside, studied how bed bugs reacted in the presence of water. They discovered that these insects generally steered clear of wet surfaces, although the younger bugs were more adept at doing this. Their findings not only provide insight into these unwelcome pests but could also improve pest control strategies.
“These findings show that wet surfaces are inherently unpleasant for bed bugs, a crucial consideration for developing liquid-based control methods that prevent them from escaping freshly treated areas,” the researchers noted in their paper, published in December in the Journal of Ethology.
An Accidental Revelation
This discovery, like many in science, came about quite unexpectedly.
Entomologist Dong-Hwan Choe was getting ready to feed bed bugs in his lab when he noticed that a feeding apparatus had leaked blood into one of the vials containing the bugs. To his surprise, the bed bugs avoided the area with the wet blood.
“The leaked blood was gradually soaking the paper at the top of the vial. I thought the bed bugs would enjoy drinking from the paper,” Choe reflected. “But instead, they actively steered clear of the wet paper. They wouldn’t even approach those areas.”
Intrigued, Choe and his team soaked some paper with water and saw the same behavior. They then conducted further experiments, observing how both young and adult bed bugs reacted to wet versus dry surfaces.
In total, the researchers found that bed bugs consistently spent less time on wet surfaces compared to dry ones. Almost 90% of the time, they would retreat from wet areas before getting close enough to touch the water. Interestingly, juvenile bed bugs, or nymphs, were about 60% faster than older bugs at fleeing from water, suggesting a heightened aversion to it.
While this marks the first reported instance of bed bugs having a fear of water, the researchers find it quite logical. These insects are extremely flat, and water’s strong adhesive forces could block their spiracles—their breathing pores—at the belly, making even a small amount of water potentially deadly.
Implications for Pest Control
Bed bugs were on the verge of being eradicated around the mid-20th century, but they’ve made a significant resurgence in recent years. Although their populations may have stabilized, they continue to be an annoying indoor pest. Finding effective methods to permanently remove them from our homes is crucial.
Other studies indicate that bed bugs have developed widespread resistance to common insecticides, underscoring the need for a more holistic approach to pest management that doesn’t rely solely on chemicals. These findings suggest that exterminators must be cautious when employing liquid-based removal techniques.
“If the insecticides don’t eliminate the bed bugs immediately, they’ll likely leave treated areas and move to other spots,” Choe warned.
In the end, it’s a bit reassuring to know that even these real-life terrors have something they’re afraid of.
