Giant Joro Spiders Could Cover the Entire East Coast, Scientists Say

Giant Joro spiders could soon colonize the entire eastern coast of the U.S., scientists have warned.

The brightly colored spiders are an invasive species that first arrived in the U.S. from East Asia in 2013 and have since become prevalent in Georgia.

A study published in the journal Physiological Entomology said that the Joro spider could be expected to spread beyond its current range in the southeastern corner of the U.S. thanks to some evolved attributes.

Joro spiders can grow up to 3 inches long and weave large webs with golden or yellow-looking silk. They can be spotted by distinctive bright yellow and black stripes on their legs and abdomens. The spiders use venom to catch and kill their prey, but they are not considered dangerous to humans.

Scientists believe the spiders were first transported to the U.S. on ships and could be expected to spread beyond the southeastern states by similar means with human transport.

"The potential for these spiders to be spread through people's movements is very high," study co-author from Benjamin Frick from the Odum School of Ecology at the University of Georgia (UGA) said in a statement. "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."

To come to their conclusions the researchers compared the Joro spider with a similar spider called the golden silk spider that also lives in the southeastern states after arriving from the tropics.

They found that, despite some similarities, Joro spiders have a metabolism twice as high as golden silk spiders and heart rates 77 percent faster when exposed to low temperatures. This means they could survive the colder temperatures found further north.

The scientists behind the study said the spiders were already endemic and advised people against needlessly killing them.

"People should try to learn to live with them," study author Andy Davis from the Odum School of Ecology at the University of Georgia said in a statement. "If they're literally in your way, I can see taking a web down and moving them to the side, but they're just going to be back next year."

Georgia residents have described finding increasing numbers of the webs throughout the state recently leading experts to assume they are already spreading rapidly through the region.

Joro spiders originated in Japan and are found throughout the country which has a comparable climate to the East Coast of the U.S.

"Just by looking at that, it looks like the Joros could probably survive throughout most of the Eastern Seaboard here, which is pretty sobering," Davis said.

Stock image of a joro spider
Stock image of a Joro spider. Experts have warned the spiders could soon become widespread on the eastern coast of the U.S. David Hansche/Getty Images