Nature

Giant, parachuting Joro spiders expected to arrive in NY and NJ this summer

Joro spiders have already spread across several states, and the species' range is expected to keep expanding to new ones โ€” including the northeast

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Arachnaphobes, look away โ€” there's a giant invasive spider coming to the tri-state this summer.

Joro spiders are expected to start showing up in New Jersey and New York this summer, spreading up from the southeastern U.S., where they have been proliferating.

The yellow arachnids are native to East Asia, but the creepy crawlers have been around in Georgia for about a decade. A recent peer-reviewed study conducted by David Coyle, a scientist and assistant professor in the Department of Forestry and Environmental Conservation at Clemson University, found that the species is "here to stay" in the U.S. as it spreads rapidly around the country.

โ€œ(The data from the study shows) that this spider is going to be able to inhabit most of the eastern U.S.,โ€ Coyle said. โ€œIt shows that their comfort area in their native range matches up very well with much of North America.

Adding to nightmares, the spiders are light enough to travel through the air, making it even easier for them to spread.

But there is good news: Even though its size tends to freak people out, the species is relatively harmless to humans and pets. The spiders eat mosquitoes, yellowjackets, stink bugs and even spotted lanternflies.

Joro spiders have a body of around an inch or so long, but their legs can span about four inches long โ€” meaning they can measure up to the size of a human palm. The females are larger and brightly colored, whereas the males are brown and smaller.

Here's what to know about the Joro spider:

How did Joro spiders get to the U.S. to begin with?

Joro spiders, also known as "Trichonephila clavata," are native to East Asia. It's believed the species likely made its way to the U.S. via a shipping container.

Are Joro spiders orb-weavers?

Joro spiders are in the family of orb-weavers, which spin large, orb-shaped webs. They look similar to garden spiders and banana spiders.

Do Joro spiders fly?

The pattern in which Joro spiders have spread "suggests it is primarily driven by natural dispersal mechanisms, such as ballooning," according to the study. Ballooning is when spiders move through the air like a parachute by releasing "sail-like trails of silk that lift them up and off into the wind," per National Geographic.

The study said human-mediated transport can't be discounted, either, in regard to the spread of the species.

Are Joro spiders dangerous?

While Joro spiders may appear frightening to some, they are relatively harmless to people and pets, a University of Georgia study from earlier this year said. In fact, that study found that Joro spiders may be the shyest spider ever documented.

The spiders will only bite if they're cornered and even then their fangs likely wouldn't be large enough to pierce human skin, according to the University of Georgia study.

Another positive about the spiders: they don't want to go inside homes, according to Coyle. They will instead spin webs on the outside of houses or other structures. If a Joro spider needs to be moved, Coyle suggests using a broom or stick to place it elsewhere.

What do Joro spiders eat?

Joro spiders aren't exactly picky eaters. Coyle said they "don't seem to care what gets in their web."

"They're just as likely to eat brown marmorated stink bugs as they are to eat a Monarch butterfly," he added. "To say theyโ€™re more beneficial than another spider is just simply wrong โ€” theyโ€™re a spider โ€” and if something gets caught in their web, itโ€™s going to get eaten. And they donโ€™t care if itโ€™s a rare native pollinator and there are only a few of them left in the world or if itโ€™s a brown marmorated stink bug."

An interesting find from Coyle's study is that Joro spiders are displacing native species, along with having other negative impacts. But it's unclear exactly why other species are being negatively impacted by Joro spiders.

โ€œThese are not just benign spiders coming to catch and kill bad things; these are pushing out native species and catching and killing whatever happens to get in their webs,โ€ Coyle said. โ€œAre they bad or good? Itโ€™s very nuanced depending on your perspective.โ€

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