If you live in Atlanta, there’s a large chance you’ve come into contact with the now common Joro Spider. Measuring in at 3 inches long, Joro spiders have neon-yellow abdomens and long legs with bright yellow stripes. They build incredibly large and intricate webs and have seemingly positioned themselves as a super predator of arachnid world, catching basically any insect foolish enough to get caught in their web.
Joro spiders are native to East Asia and were first introduced to Georgia in 2013. Since then, their populations have been increasing, but still remain mostly confined to North Georgia and Southern Tennessee. These spiders have begun to dominate northern Georgia, setting up shop in forests and urban areas. There is growing concern about their growing populations. Joro spiders are venomous, and families are concerned about the safety of these spiders around their pets and children. In addition, invasive species often pose threats to local ecosystems, and there is growing concern for how the Joro invasion is going to affect native flora and fauna. Lastly, it appears that the Joro population is slowly starting to spread northward, and many are beginning to worry that the Joro troops are planning to dominate the entire east coast, and maybe even… the world.
To address these concerns, I would like to begin with the assertion that Joro spiders look a lot scarier than they really are. While these spiders are venomous, their venom is only potent enough to kill small insects. If a human is bit by a Joro spider, which is unlikely, it will hurt less than a bee sting and will not require medical attention. Despite their threatening stature, Joro spiders are, for lack of a better word, babies. They are a very docile and non-aggressive species of spider. A study conducted in 2023 by blah, was evaluating how different species of spiders reacted to a environmental stressor. When blown with a light puff of air, most spiders in the study responded by freezing for less than a minute. The Joro spider, however, reacted to the stressor by freezing for over an hour. It is safe to say that these spiders are not going to attack humans or animals they see as a threat.
Concerns about how Joro Spiders may impact local ecosystems are much more valid. As of right now, scientists are unsure of exactly how these new Joro spiders will impact the environment. It is clear that they have cemented their spot as top predators of the arachnid world, and it is likely that they will out-compete native spider populations for food. This could threaten local spider and insect populations, which could lead to eventual destabilization of ecosystems, but the extent to which ecosystems will be affected is still up for debate.
The good news is that many scientists are optimistic about the effects that Joro Spiders will have on the environment, some going as far as to say that they may be beneficial. In general, spiders are key pillars of healthy ecosystems, as they control insect populations and act as a key source of protein for birds. Additionally, there is no evidence that Joro Spiders pose any threat to the environment apart from potentially destabilizing insect and spider populations. Take the invasive Spotted Lanternfly, which was introduced to the US from China in 2014 These insects have had disastrous consequences on agriculture due to their intensive feeding of various trees and crops. Americans are advised to kill these lanternflies on sight due to their environmental impact. Luckily for it, the Joro Spider has yet to exhibit any behaviors that could pose a similar threat and could warrant similar measures. In fact, Scientists are optimistic that Joro Spiders could help the environment by preying on another invasive species, the Brown Mamorated Stink Bug. This bug was introduced to the US from East Asia in 1998 and caused significant agricultural damage through their feeding habits. There are very few natural predators of this stink bug, which has allowed their populations to boom. The Joro Spider, however, will happily feast on this stink bug, which could potentially keep their population in check.
So, where are Joro Spiders headed now? As of right now, Joro Spiders are confined to the southeast, concentrated in Northern Georgia, Tennessee, and the Carolinas. There have been a few sightings of these spiders in Oklahoma, Maryland, and West Virginia, likely from being transported by car; however there is not evidence of any permanent or expanding Joro populations this far north. Joro Spiders prefer the warm climate of the southeast, and they are unlikely to move farther north. However, with climate change continuing to progress, it is possible Joro Spiders may increase their reign as a larger portion of America becomes habitable for them. At this point, it is difficult to predict.
So, to answer the question, “Are Joro Spiders Going to Kill Us All?” is a definite no. While their large webs and bright colors might seem intimidating, Joro spiders are quite harmless to humans and pets. Although their presence does raise ecological concerns, particularly for native spider populations, scientists remain cautiously optimistic. For now, residents of the Southeast can coexist peacefully with these giant newcomers and perhaps even appreciate the role they play in keeping insect populations in check.
Works Cited
Bugwood. (2024, November 5). Home. Joro Watch. https://jorowatch.org/
Joro Spider is a unique exception to a major threat. Big Think. (2022, May 20). https://bigthink.com/life/joro-spider-invasive/
Meadows, K. / S. (2021, September 6). Joro spider update: Controlling this invasive species. Joro Spider Update: controlling this invasive species.
https://gardeningsoul.blogspot.com/2021/09/joro-spider-update-controlling-this.html
Pappas, S. (2024, June 11). No need to panic about the joro spiders. Scientific American. https://www.scientificamerican.com/article/millions-of-joro-spiders-are-moving-up-the-east-coast-heres-what-to-expect/
Spotted lanternfly. Spotted Lanternfly | National Invasive Species Information Center. (n.d.). https://www.invasivespeciesinfo.gov/terrestrial/invertebrates/spotted-lanternfly
Walling, M. (2024, June 7). Everything you need to know about the invasive joro spider. PBS. https://www.pbs.org/newshour/science/everything-you-need-to-know-about-the-invasive-joro-spider
