Giant venomous flying spiders will not parachute into New Jersey this summer

For years, scientists in the Northeast have been anticipating the arrival of the giant, flying, venomous jorō spider. Recent media coverage has led many to believe the spider will arrive in New Jersey this summer. Local experts say not so fast.

Jorō spiders were first seen in the U.S. in 2014, according to researchers at Pennsylvania State University, likely hitching a ride in shipping containers or potted plants brought from Asia to the state of Georgia. (The spotted lanternfly invaded Pennsylvania in a similar manner.)

From Georgia, the invasive species have moved up the East Coast. By September, they had reached the Baltimore suburbs.

Much of the recent media reporting surrounding jorō spiders, reminiscent of the “murder hornets” scare in 2020,stem from a January blog post by New Jersey Pest Control. However, just as murder hornets proved to be mostly a nonissue for humans and pets (eventually being subdued in Washington), the arrival of jorō spiders won’t come anytime soon, said Pennsylvania State entomologist Michael Skvarla.

“It seems like a big media craze the same way murder hornets were a couple years ago,” Skvarla said. “Jorō spiders will eventually get to New Jersey and New York, but it’s probably not going to be next year. Maybe in the next 10 years.”

Even when they do arrive, it won’t be a doomsday scenario, either.

“They’re scary because they’re big, not because they’re actually dangerous. People already live with large golden silk-orb spiders all the time. Jorō spiders will build a big web and that might be annoying but they’re not going to come out and bite you,” he said.

Jorō spiders, known as Trichonephila clavata, are spiders commonly found in China, India, Japan, North and South Korea, Taiwan, and Vietnam. In Japanese, jorō spiders are known as jorō-gumo, which translates to “entangling or binding bride,” according to Penn State Extension.

Female jorō spiders are brightly colored and can grow up to four inches, making webs up to 10 feet wide. For context, the common house spider is smaller than a quarter-inch, according to the National Wildlife Federation.

Male jorō spiders are brown, smaller, and can’t spin their own webs. Females lay a single sac that can contain up to 500 spider eggs. Like other spiders, their main prey are smaller insects.

While jorō spiders are venomous, they don’t pose a known threat to humans or pets. Skvarla said a human will only be bitten by a jorō spider if the spider feels attacked or provoked.

“They’re not very venomous at all, and they’re very reluctant biters,” Skvarla said. “Even if you pick them up, they might bite in defense if you grab one, but the fangs are so small that it’s hard for them to pierce human skin despite their large size.”

A bite from a jorō spider is similar to a sting of a yellow jacket wasp. It may hurt, but in most cases, there won’t be any severe outcomes. If a person is allergic to spider bites, side effects could be worse.

Jorō spider younglings, like several species of spiders and invertebrates, can travel long distances using a technique called “ballooning” or “kiting,” where the spider heads to a high surface and shoots webs of silk into the air to be caught by the wind. Only baby spiders can “fly”; adults don’t have this ability.

Skvarla said jorō spiders travel around 10 miles every year. The bulk of the spiders in the U.S. have only traveled about 80 miles since their arrival in Georgia a decade ago, according to reports from 2022.

At the rate that jorō spiders typically travel, Skvarla expects the spider to land in the region sometime in the next 35 years.

“It’s a slow burn. Based on current spread models, it’s probably going to be 20 to 40 years before that happens,” he said. “But, if somebody accidentally transports the eggs, like how they got into the U.S., they could pop up anywhere much faster.”

Once jorō spiders arrive in Pennsylvania, they shouldn’t have any problem establishing themselves due to the state’s similar climate to Japan. In 2021, scientists at the University of Georgia were able to prove jorō spiders can withstand below-freezing temperatures, meaning they could make the trek to even colder climates up north.

Nothing. There’s no preparation for the arrival of jorō spiders. While jorō spiders may impact the environment in some way, like reducing insect populations or hybridizing with other spiders, it’s not yet known to what extent, said Skvarla.