Large invasive spiders originally from East Asia are making their way up the U.S. East Coast, some officials have warned, although it’s disputed whether they are dangerous.
The spiders have a bright color, with females being yellow and black, while male Joro spiders are smaller and brownish. Some reports and studies have suggested that, with their legs included, they can get up to 4 inches in size.
“As the Joro spider invasion continues its northward trajectory, the possibility of their arrival in New Jersey later this year has heightened concerns among residents and authorities alike,” New Jersey Pest Control said on its website. “The potential for these spiders to establish populations in new regions raises questions about how local ecosystems will respond and adapt to their presence.”
Southern Adventist University professor David Nelsen, who contributed to the research, said that “because of how far Joros have already spread and how fast they continue to spread,” it might pose a threat to native species.
Are They Dangerous?
In an interview with The Epoch Times, Mr. Nelsen said that Joro spiders “are venomous” but in “a technical sense.”“What most people mean by venom and venomous is, ‘Will it hurt people?’ This is known as medical relevance. In this case, these spiders are not medically relevant to humans. They may cause mild pathophysiological consequences like swelling and pain but nothing appreciable,” he said, adding that repeated exposure could result in an allergy.
“However, this would be exceptional in the Joro case because they are not aggressive,” he continued to say.
There also have not been “any medically relevant reports of envenomation to humans or pets” as a result of a Joro spider bite, Mr. Nelsen continued.
Responding to claims that the spiders are spreading across the United States into places like New York, he said that modeling shows that if the Joro make it to New York, “they can persist” in the state. However, he cautioned that he doesn’t know if or when they will make it to the state.
“Invasive species can suddenly jump to further locations, but this is a chance event that can’t be predicted,” the professor said before cautioning: “No one can predict that.”
“In fact, Joros are relatively harmless to people and pets,” it added. “Joros won’t bite unless cornered. And even if you did manage to somehow annoy a Joro into biting you, its fangs likely wouldn’t be large enough to pierce your skin.
While headlines have suggested the spiders are capable of flying, researchers say that only the juveniles use their webs to float upward using wind currents to travel long distances.
