However, don’t use the invasive, biting insects as an arachnid repellent in your house.
Bring on the fire ants to make a spider flee. Or, more precisely, their chemical signals.
Researchers report in Royal Society Open Science on May 19 that certain spiders commonly found in North American homes resist weaving webs in chambers that recently housed European fire ants. Chemical traces were most likely left behind by the ants, according to the researchers. Since ants often eat spiders, this may be a threat to the arachnids. The reaction suggests that the insects may be a source of naturally occurring spider repellents.
“A lot of people are afraid of spiders, and there’s nothing on the market that is reliable that keeps the spiders away,” says Andreas Fischer, an arachnologist at Simon Fraser University in Burnaby, Canada.
False black widow spiders (Steatoda grossa) were housed in a glass container with three related chambers by Fischer and his colleagues. In empty compartments that had previously housed European fire ants (Myrmica rubra), an invasive species in North America, the arachnids were less likely to settle down. Other spider species, such as the black widow (Latrodectus hesperus), cross (Araneus diadematus), and hobo (Eratigena agrestis), avoided the former fire ant chambers as well.
According to Fischer, the discovery is exciting but not yet ready for use in the real world.
“I really hope that people don’t go out there and get European fire ants into their garden to get rid of spiders.”
The ants are vicious, “horrible bugs” with stinging bites that are difficult to eradicate. Another form of fire ant native to South America (Solenopsis invicta) is one of the world’s most expensive invasive species.
The researchers want to find out what chemical frightens the spiders and see if it can be replicated in the lab. The researchers will then check to see whether the possible spider repellent is poisonous or acts as an ant homing beacon.
“That’s the last thing we want, that we get rid of spiders but attract ants,” Fischer says.