Joro Spiders: Huge Flying Arachnids Could Descend On PA

PENNSYLVANIA — If stink bugs make you squeamish, you aren't going to like this. Pennsylvania and much of the East Coast soon can expect to see giant flying spiders in the air.

The Joro - or Trichonephila clavata- which swarmed Georgia by the millions last summer, could be headed northward and potentially colonize the entire Eastern Seaboard. That sobering prediction came last month in research published by the University of Georgia.

Joro females can measure 3 inches across when their legs are fully extended. That's creepy enough if you saw one in a web, but what about in the air? These spiders actually "fly" using their webs as a form of a parachute as the wind carries them.

Some have traveled as far as 100 miles, making colonization of new territory relatively easy.

Joros also are expert stowaways, having arrived in the United States from Japan in a shipping container in 2013. Millions of the spiders were spotted across more than 25 countries last year, Life Science reported.

The Joro also could easily travel to a new location by riding on a car or hiding in luggage, experts say.

"The potential for these spiders to be spread through people's movements is very high," said
Benjamin Frick, co-author of the study and an undergraduate researcher with the University of Georgia. "Anecdotally, right before we published this study, we got a report from a grad student at UGA who had accidentally transported one of these to Oklahoma."

Once Joros arrive in Pennsylvania, they could be here to stay. The study found the Joro actually has a high-enough metabolism to survive the colder temperatures in a typical Philadelphia or Pittsburgh winter that kill off many of its cousins.

"It looks like the Joros could probably survive throughout most of the Eastern Seaboard here, which is pretty sobering," Andy Davis, a corresponding author of the study and a research scientist at the Odum School of Ecology, said in an article by UGA.

Joros can bite when cornered, but they are relatively harmless as their fangs aren't often capable of breaking human skin. You needn't fear them harming your pets, as their diet usually prefer mosquitoes, biting flies and other invasive species - including those intrusive brown marmorated stink bugs.

So while Joros likely will startle people in Pennsylvania some point, Frick said they shouldn't be terrified by them.

"There's really no reason to go around actively squishing them," Frick said. "Humans are at the root of their invasion. Don't blame the Joro spider."

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