(NEXSTAR) – Joro spiders (Trichonephila clavate) are getting ready to hatch across parts of the Southeastern United States — and likely well beyond, if previous years are any indication. The invasive species, which is native to China, Japan, Korea and Taiwan, had arrived in North America at least as early as 2013, when it was spotted in parts of Georgia. It has since been reported in multiple states in the Southeast, but also further north in places like Pennsylvania and Massachusetts, and as far west as California, according to the University of Georgia’s Joro Watch database. Researchers have attributed their spread to the spider’s fast metabolism and heart rate, which helps it thrive in both warmer and cold temperatures. But they’ve also been known to take part in a practice called “ballooning” — floating through the air by strands of their own silk — to quickly expand their territory. “Ballooning spiderlings can travel tens to hundreds of miles, especially if they are picked up by strong winds and storms,” a factsheet published by Penn State Extension explains. These attributes have contributed to the Joro spider’s increased presence in America. Joro Watch, as of its latest update, had collected reports of Joro populations (or just single sightings) in Alabama, California, Georgia, Maryland, Massachusetts, North Carolina, Oklahoma, Pennsylvania, South Carolina, Tennessee, Virginia and West Virginia. The majority of their footprint, however, is centered around Alabama, Georgia, North Carolina, South Carolina and Tennessee. Researchers wouldn’t be surprised if their footprint expands after their eggs begin hatching in April and May. The Joro’s penchant for making its habitat in both rural and urban environments will likely “aid its spread” in the coming years, University of Georgia (UGA) researchers noted in a 2024 study. “I don’t know how happy people are going to be about it, but I think the spiders are here to stay,” Alexa Schultz, the study’s co-author, said. When their populations spring up in new regions, they’re easy to spot. While the males are smaller and mostly brown, females have yellow bodies with blue-black bands, red spots and long legs. They can also grow up to three inches in diameter, according to the Associated Press. They begin hatching in April and May, but the easiest time to spot them is further along in the fall, between August and October, according to experts. The Joro may also bite humans, but only in very rare cases when they feel threatened. Even then, their fangs may be too short to pierce the skin. "These spiders may be big, but they would much rather run away from you than bite. And if someone is careless enough to get bitten, the symptoms will likely be milder than a mosquito bite,” David Nelson, a professor at Southern Adventist University who conducted a recent study on Joro bites, told Clemson News. Joro spiders, despite being invasive, may not pose much of a threat to their new ecosystems, either, though researchers are still studying their effects. In the meantime, humans are not yet advised to go out and kill Joro spiders en masse, as they don’t pose an immediate threat, and because pesticides may do more harm to the ecosystem than the Joro might. On the other hand, David Coyle, a scientist and assistant professor at Clemson University, acknowledged that homeowners may want to limit the Joro’s presence on their properties. “A broom or stick works just fine,” he told Entomology Today in 2025. “But if you feel you need pesticides, we recommend sticking with a product labeled for spider control.”