Hailing from East Asia, Jorōs is one of many so-called golden orb weavers, named after the shiny silk they use to spin webs (which, by the way, can be as much as 10 feet wide). The spider was first noticed in the US by scientists in Colbert, Georgia, in 2014, though local records suggest it may have existed a few years earlier. Colbert is located near a hub of warehouses and distribution centers, making it likely that the spider arrived by inadvertently hitching a ride on an international freighter.
In 2020, the Jorō population skyrocketed. Scientists believe they spread primarily through a technique called ballooning: Baby spiders climb high, shoot silk and glide down the air currents to their next destination. That’s when the spiders first caught the attention of the media. A second wave of news came with the discovery that unlike native orb weavers, Jorōs can tolerate colder climates. Some articles referred to palm-sized parachuting spinners that would soon be flying down the East Coast. Others portrayed them as positive – perhaps Jorōs would hunt harmful invasive species, such as stink bugs, and keep them at bay. But neither has been proven true.
“There is a strong temptation to label them as good or bad,” said University of Florida arachnologist Angela Chuang, a co-author of the paper. “But we just don’t know enough to say yet.” Chuang’s previous work found that 47 percent of all spider news is inaccurate, with misidentified images or factual errors about their anatomy and venom toxicity. In addition, 43 percent of the articles are exaggerated, exaggerating the size or hairiness of spiders and associating them with trigger words, such as terrifying, nightmarishand deadly– that can fuel arachnophobia.
Negative reporting distorts perceptions about the risk that spiders pose to humans and shapes people’s decisions on wildlife conservation efforts. At worst, sensational accounts lead to loss of money and resources: Spider sightings have caused unnecessary school closures and made people do it extreme measures of extermination. Increased use of pesticides (which is only a temporary fix, Coyle says) can hurt homeowners’ finances as well as nearby wildlife.
On the other hand, Coyle says, overly positive reporting is also disingenuous, as it can give the public a false sense of security before scientists have thoroughly assessed the ecological and economic impacts of a new species.
The reason it’s so hard for scientists to predict the future is because spider invasions have been largely underexplored. Unlike insects, they are not agricultural pests, so monitoring invasions has a low economic priority. Most are also harmless. “The vast majority of spiders pose no threat to humans and do a great job,” said Catherine Scott, a behavioral ecologist at McGill University. They are essential predators that help maintain balance in almost any terrestrial ecosystem.
But most experts agree that the Jorōs must have some effect, especially because of their rapid population growth. Today, they cover an estimated 46,000 square miles (120,000 square kilometers), most concentrated in northern Georgia, though a few have been seen in northern Washington, D.C. and far western Oklahoma. “There’s just no conceivable way they could seamlessly slip into the ecosystem without causing some ripples,” says Coyle. His hunch, based on some preliminary research work, is that Jorōs will likely drive out smaller native spiders, which could have a cascading effect further down the food chain. They are also less likely to deplete pollinator populations critical to high crop yields if too many bees and butterflies become entangled in their webs.
