A Choro spider was seen on October 24, 2021 in Johns Creek, Georgia.Just a matter of time before they spread to most of the continental United States
Alex Sands/AP
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Alex Sands/AP
A large, brightly colored invasive species called the choro spider is migrating across the United States. Populations have been growing in parts of the South and East Coast for years, and many researchers believe it’s only a matter of time before they spread to much of the continental United States
But spider experts say we shouldn’t worry too much about them.
“My sense is that people like weird, wonderful and potentially dangerous things,” said David Nelson, a biology professor at Southern Adventist University who has studied the expanding range of Choro spiders. “That’s one of the things that checks all the public hysteria.”
Instead, scientists worry about the growing prevalence of invasive species that can cause damage to our crops and trees — a problem made worse by global trade and climate change, which make local environmental conditions previously unavailable during cold winters The survival of pests becomes more comfortable.
“I think this is one of those ‘canary in the coal mine’ types of species where it’s striking and gets a lot of attention,” said Hannah Burrack, professor and chair of the Department of Entomology at MSU. Concern. But the shy animals pose little risk to humans, instead exotic pests such as fruit flies and tree borers can cause more damage, Burak said.
“This is a global problem because it makes everything we do in terms of conservation, agricultural production, human health more difficult to manage,” she said.
What is a Joro spider?
The Choro spider is a type of spider known as an orb-web spider, named for its whorl-shaped web. Native to East Asia, they have bright yellow and black colors and can grow up to three inches (8 centimeters) when their legs are fully extended.
However, at this time of year they are difficult to spot as they are still in the early stages of their life cycle and are only about the size of a grain of rice. A trained eye can spot their softball-sized netting on the front porch or the golden threads they cover the grass. Adult beetles are most common in August and September.
Where are they going?
David Coyle, an assistant professor at Clemson University, said scientists are still trying to figure it out. published. Their central population is primarily in Atlanta but extends into the Carolinas and southeastern Tennessee. Coyle said the satellite population has taken root in Baltimore over the past two years.
As for when the species will become more common in the Northeast, what does their study ultimately show? “Maybe this year, maybe ten years, we really don’t know,” he said. “They’re probably not going to make that much progress in one year. It’s going to be a series of incremental steps.”
Can they fly?
Babies Can: Using a strategy called “ballooning,” young choro spiders can use their webs to harness the Earth’s winds and electromagnetic currents to travel relatively long distances. But you won’t see a fully grown Choro spider take off.
What do they eat?
Choro spiders will eat anything caught in their webs, mostly insects. This likely means they’ll compete with native spiders for food, but that might not be all bad— Andy Davis, a research scientist at the University of Georgia, has personally documented that the food Choro catches every day also feeds native birds. kind.
As for the hope of some observers that choro spiders will devour the invasive spotted lanternfly that’s destroying trees along the East Coast? They might eat some, but there’s “zero chance” they’ll have an impact on population numbers, Coyle said.
Are they dangerous to humans?
Nielsen said choro spiders, like all spiders, have venom, but they are not deadly or even medically relevant to humans. In the worst-case scenario, a Joro bite may be itchy or cause an allergic reaction. But this shy creature tends to avoid humans.
What will really harm humans one day is the widespread introduction of other organisms, such as the ash borer or a fruit fly called the spotted-wing Drosophila, which threaten the natural resources on which we depend.
“I’m trying to be scientifically objective about this. It’s a way of protecting myself from sadness. But there’s so much ecological damage happening around the world for a variety of reasons, much of it caused by humans,” says David Si said. “To me, this is just another example of human impact on the environment.”
