Experts are advising the public not to be alarmed following the sighting of an invasive Joro spider in Beacon Hill, the first reported appearance of the species in Massachusetts.
The Joro spider, which is identified by its yellow coloring and legs that can reach up to four inches long, is not harmful towards humans, said Jessica Garb, an associate professor of biological sciences at University of Massachusetts Lowell.
“There’s nothing to be really worried about because it’s not going to attack you or bite you,” Garb said. “The worst that could happen to someone is they might walk into the web, and somehow the spider is on them.”
The spider usually appears during the fall months and exhibits bright colors and striped legs, according to Terminix. It weaves distinct three-layered, orb-shaped and gold-tinted webs.
Boston University Professor of Biology James Traniello, who studies insect behavior and ecology, said the Joro spider is not a concern “from a medical standpoint” due to its lack of aggressiveness.
“It’s incapable of breaking human skin,” Traniello said. “The venom is not fatal.”
Nolan Horn, treasurer of BU Bug Club, compared the Joro spider’s bite to “somewhere between a mosquito and a bee sting.”
Traniello said the spider’s ability to survive colder climates similar to New England’s is limited, and it is unknown if the species can withstand a typical winter in Boston.
“It’s just too early to say what’s going to happen,” Traniello said. “The ecology of the Joro spider is not really known that well. There are very few people that are studying it.”
Garb said although the risk to local ecosystems is uncertain, it will not have a “direct effect on any one insect.”
There is some concern that the species could compete with native spiders for food and space, but no conclusive research has been done to determine a long-term impact, Garb said.
“Some people might think that’s a good thing,” Garb said. “It could be just potentially more of an issue of if there are spiders that would sort of occupy the same ecological niche that are already established here and native.”
Horn said while invasive insects in general “should be of concern,” the Joro spider specifically is “being sensationalized by the fear of spiders.”
“In reality, and this is the case for pretty much all bugs, they’re going to be more afraid of you than you are afraid of them,” Horn said.
