Joro Spider Spreads Its Web Across the South
A large and colorful spider, known as the Joro spider, is making its presence felt across many southern states, and experts believe it’s here to stay. This spider can grow up to 4 inches across and is recognizable by its bright yellow, blue-black, and red markings. First seen in Georgia in 2013, it likely arrived in the U.S. as a stowaway on shipping containers or planes from Asia.
Currently, Joro spiders have been spotted in Georgia, North Carolina, South Carolina, and Tennessee. Researchers at Penn State suggest they may continue spreading throughout the eastern U.S., possibly reaching as far north as Pennsylvania and even other warmer coastal areas.
To travel, Joro spider hatchlings use a method called “ballooning.” They release fine silk threads that catch the wind, allowing them to travel long distances. Ian Williams, an entomologist with Orkin, reports that he counted around 200 adult Joro spiders on his one-acre property near Atlanta last September.
Despite their somewhat intimidating appearance and the large, golden webs they create, experts reassure the public that these spiders are not a danger. Williams describes them as “shy” and notes that when disturbed, they often stay still for over an hour rather than attacking. Their fangs are small, making it hard for them to bite humans. If they do bite, the venom is mild, similar to a bee sting, and not medically harmful.
As an invasive species, the potential impact of Joro spiders on local ecosystems is under study. Williams expresses concerns that they may outcompete native spider species for resources.
However, these spiders are also effective hunters, preying on a variety of insects including mosquitoes and cicadas. It’s still uncertain if they take food from local garden spiders.
For homeowners wondering how to keep Joro spiders away, experts suggest using a broom or pole to knock their webs down. This could discourage them from rebuilding in the same spot. Removing spiders physically tends to be more effective than using pesticides, which may not reach spiders high in trees or on buildings.
If you see a Joro spider in a new area, consider reporting it on apps like iNaturalist to assist researchers in tracking their spread.
