After a long journey from the southeastern United States, the giant, invasive joro spider (Trichonephila clavata) has made it farther north. The invasive species was recently spotted numerous times in Bucks County, Pennsylvania, demonstrating their continuing expansion following sightings in Howard County, Maryland, over the summer.
Joro spiders are native to East Asia and likely found their way to the U.S. in container ships around 2013. They quickly spread throughout Georgia and South Carolina. Because they are hardy and can handle various climates (like freezing temperatures) it might be only a matter of time before they’re in your state.
Their migration from the southeast has been expeditated by “ballooning”—which some refer to as “flying.” While they don’t technically fly (they don’t have wings), they can travel hundreds of miles in a short amount of time, releasing silk and sailing with the wind to new locations. While it seems this invasive species is spreading far and wide quickly, it may still take a while for joro spiders to densely populate and inhabit new regions of the U.S.; experts from Penn State research say it could take up to 60 years.
What to Do if You See One
While this invasive species’ vibrant colors and intimidating size can be terrifying at first glance, remain calm—they are harmless to people and pets. And better yet, according to some accounts, they feast on spotted lanternflies, another invasive species—but one with few natural predators and a significant potential for destruction.
To learn more about how to identify joro spiders and what to do if you encounter this vibrant spider in your garden or just floating by, read our article including insight from expert entomologists.
If you have spotted a joro spider, we recommend sharing and tracking it through JoroWatch.com, a University of Georgia-powered website to document the spider’s spread as they establish populations in new locations throughout the U.S.