What are Joro spiders, are they dangerous to humans and how did they come to make a home for themselves in North America, far from their east Asian native range?
The Joro spider has hit the headlines recently thanks to research that predicts its continued spread up the US east coast. Here’s everything you need to know about the species.
What are Joro spiders?
The Joro spider (Trichonephila clavate) is a large-bodied orbweaver native to east Asia. Females usually have a bright yellow abdomen and yellow-banded legs, while males are a non-descript brown colour.
How big are Joro spiders?
The body of a female Joro spider female measures 2.8cm long, with legs stretching another 3cm or so. Male Joros are less than a quarter of that size.
Do Joro spiders bite and are they poisonous?
They do not readily bite, being one of the shyest species of spider. Joro venom is used for subduing small insects. Bites, if they happen, are not dangerous to humans, and less painful than a bee sting.
What are Joro spider webs like?
Joros are orbweavers, building spiral, wheel-shaped webs. Joro webs are golden and extremely strong – a citizen scientist in the US observed a cardinal perched on a Joro web, feeding off the insects trapped within it.
What do Joro spiders eat?
Joro spiders are known to prey on cockroaches, beetles, wasps, bees, butterflies, dragonflies, grasshoppers and other spiders.
Where are Joro spiders from?
Joro spiders are native to east Asia. Their range includes Japan, the Korean peninsula, Taiwan, China, Myanmar and parts of the Himalayas.
Joro spiders in the US
The Joro is thought to have been introduced to the US state of Georgia in around 2010. Though the exact route is uncertain, scientists hypothesise that it arrived in a shipping container, as is common for invasive insect species. It has since spread to at least four other southeastern states and is set continue moving north, according to recent published modelling-based research.
What is the Joro spider’s habitat?
Joro spiders are adapted to both rural and urban habitats, building webs in both natural and human-made locations including traffic lights and picnic benches.
Can Joro spiders fly?
Newly emerged Joro spiderlings release strands of silk which catch the breeze, enabling them to be dispersed over enormous distances. Related spider species have been found to travel more than 300km using this method.
More on spiders:
- Meet the tube web spider, a British spider that can pierce skin with its fangs
- Why are people scared of spiders?
- World’s most venomous spiders: Are these deadly spiders as fearsome as their reputation?
- 10 biggest spiders in the world
- Meet the purse-web spider, Britain’s tarantula