Joro spiders are making headlines with their large size and flashy colors as they spread across the eastern United States. These striking arachnids, native to East Asia, first appeared in Georgia around 2013. But are these big, yellow-and-black joro spiders a cause for concern?
Let’s explore the fascinating world of joro spiders. We’ll cover their behavior, habitat, potential impact, and what to do if you encounter one.
Table Of Contents:
- Understanding the Joro Spider (Trichonephila clavata)
- The Joro Spider’s Spread: From Asia to the Americas
- Are Joro Spiders Dangerous? Separating Fact from Fiction
- What to Do if You See a Joro Spider
- FAQs about Joro Spiders
- Conclusion
Understanding the Joro Spider (Trichonephila clavata)
The joro spider, scientifically known as Trichonephila clavata, belongs to a group of spiders called orb weavers. These spiders are famous for their intricate, wheel-shaped webs.
Appearance
Female joro spiders are particularly striking. They sport a vibrant black and yellow abdomen and legs with alternating yellow and black-blue segments. These ladies can grow quite large, reaching up to 3-4 inches across when their legs are fully extended – about the size of an average woman’s hand. Their webs, too, can be massive, with reports suggesting spans up to 10 feet wide.
Male joro spiders are considerably smaller. They typically have a more muted brownish coloration.
Habitat
Joro spiders often build their webs in areas where they’re likely to encounter humans. You might find them along forest trails, in backyards, on porches, or even strung between power lines and streetlights. These spiders thrive in busy urban areas, unconcerned by the hustle and bustle.
They seem quite comfortable coexisting with people.
The Joro Spider’s Spread: From Asia to the Americas
The journey of the joro spider from East Asia to the U.S. is an interesting one. These spiders are native to Japan, China, Korea, and Taiwan. They likely arrived in the U.S. sometime around 2013, most likely by hitching a ride on a shipping container headed for Georgia.
Ballooning: An Aerial Journey
Once in Georgia, the joro spider quickly adapted and started to spread. One of their primary dispersal methods is called ballooning. Young joro spiders, called spiderlings, release a silk thread that catches the wind and carries them away.
This allows them to travel remarkable distances. Researchers with the University of Georgia believe that joro spiders using the ballooning technique can move between 50-100 miles. Although ballooning can transport them long distances, a University of Delaware study suggests their natural spread would be closer to 10 miles per year.
A Hardy and Adaptable Species
Joro spiders have proven to be highly adaptable. Studies by researcher Andy Davis and his students at the University of Georgia showed these spiders are capable of surviving cold winters.
This hardiness makes them well-suited for the diverse climates of the Eastern U.S., stretching from Maine down to Florida. A study by Clemson University supports this observation. They predicted that the joro spider’s range could soon cover the entire Eastern Seaboard.
Their tolerance to cold weather, adaptability to various environments, and ballooning ability give them a good chance of reaching as far north as Maine. As their name suggests, these golden silk spiders are also known as giant yellow spiders due to their size and color.
Are Joro Spiders Dangerous? Separating Fact from Fiction
The joro spider’s intimidating appearance can be scary. But are they truly dangerous? Let’s look at the facts.
Venom and Bites
All spiders are venomous, and joro spiders are no exception. However, their venom is primarily meant to subdue small insects. Even though Joro spiders are venomous, a pinch from their bite rarely breaks human skin. Researchers who often handle these spiders with their bare hands haven’t found their venom to be an issue.
They experience an occasional pinch, but nothing more.
A University of Georgia study confirmed that a joro spider bite is less painful than a bee sting and typically doesn’t require medical intervention.
Shy and Docile Nature
Perhaps the most surprising trait of joro spiders is their incredibly shy disposition. While it is true they are a relatively new invasive species to the Eastern U.S., they don’t pose much of a threat. Research has revealed them to be surprisingly timid, maybe even the “shyest” spider species ever studied.
Scientists from the University of Georgia, specifically the Odum School of Ecology, found that when startled, joro spiders will freeze and remain completely motionless for up to an hour. This is much longer than other common spiders. They exhibit a much longer “freeze” response. They’re actually more scared of us than we are of them.
Impact on the Ecosystem
The long-term ecological impact of joro spiders in the U.S. is still being studied. They’ve shown they aren’t picky eaters and will eat anything caught in their webs. Joro spider feasts consist of anything that happens to fly by, including insects like brown marmorated stink bugs (which are pests) and monarch butterflies.
While this isn’t necessarily bad, scientists aren’t sure what effects these eight-legged eating habits will have on the local ecosystem in the years to come.
What to Do if You See a Joro Spider
Joro spiders, even though they appear menacing, are beneficial for pest control. Their golden webs catch a variety of insects that homeowners normally pay pest control companies to get rid of.
Here are some guidelines for managing Joro spiders around your home:
- Appreciate their role: Acknowledge their presence and their benefits as natural pest controllers. Their presence means there are probably fewer annoying insects around your house.
- Relocation, if necessary: If a web is in a high-traffic area and is posing a nuisance, you can try gently relocating the spider. Use a broom or a stick to carefully guide the spider and its web to a less disruptive location. Avoid harming the spider.
- Web removal: If you do need to remove a joro spider web, use a broom or stick. This spider’s webs, unlike other spider webs, are strong. Their bright golden silk may even make them hard to miss. According to a study done at the University of Georgia, some mature female joro spiders’ webs are 10-feet long. They usually rebuild their webs after removal, but repeatedly doing this may deter the spider from returning to that particular spot.
- Leave them alone: The best course of action, whenever possible, is to simply leave the spiders alone. They won’t bite unless threatened or cornered, and they can be fascinating creatures to observe. You can teach your children about joro spiders, how they make webs, and what they eat.
FAQs about Joro Spiders
Are Joro spiders harmful?
Despite their imposing size, joro spiders pose little threat to humans and pets. They are shy and not known to bite aggressively. Although they do have venom, their bites rarely break the skin. These bites usually cause only mild discomfort comparable to a bee sting. Unless someone is highly allergic, their venom should be of no real concern.
What should you do if you encounter a joro spider?
It’s best to leave joro spiders undisturbed. But you can always admire their colorful webs or, if you’re brave enough, observe the spider at work. If its web is in an inconvenient location, gently guide the spider and web with a stick or broom to a new spot.
What’s the problem with joro spiders?
Whether joro spiders are a problem is still being investigated by scientists. There are some concerns about their long-term ecological impact as they spread across the U.S. Some worry they will outcompete native spiders, or affect insect populations. They also create large, strong webs which may be a nuisance to some people. But their appetite for pest insects can be considered a good thing.
Where do joro spiders live in the US?
As of right now, they are prevalent throughout the southeastern U.S. This includes Georgia, South Carolina, North Carolina, and Tennessee. However, scientists at the University of Georgia believe joro spiders could eventually spread up the Eastern Seaboard . There have been reports of sightings in Oklahoma, Maryland, and West Virginia. So far these appear to be isolated occurrences.
Conclusion
The arrival and spread of the joro spider have generated a lot of attention and curiosity. They are unique in appearance and web-building skills. Despite some initial concern, research has revealed they are docile, timid creatures. They pose minimal risks to people. Though research is ongoing about their impact, for the moment, they appear to have integrated without causing significant disruption to the Eastern U.S.
So, the next time you spot a Joro spider, take a moment to appreciate its striking colors and fascinating lifestyle. Remember, there’s no need to be scared of this gentle giant.