The Yellow Garden Spider (Argiope Aurantia)
They're big, bright and . . . well, sort of creepy looking, especially when they're "wrapping up" a pretty butterfly or moth for dinner. But despite all that, yellow garden spiders (Argiope aurantia) are great to have in your garden.
Like toads and salamanders, these spiders are sensitive beings. They're insect predators that can be handy to have around, and their presence in your yard is a sign that the ecology is a healthy, balanced one.
Yellow Garden Spiders Are Beneficial Predators
If you see one of these spiders in your landscape, don't squash it! It's one of the good guys (most of the time). It even wears a big white "hat" (its cephalothorax—fused head and thorax).
What Are the Benefits of Yellow Garden Spiders?
Like praying mantises, these spiders catch, kill and eat a wide variety of prey, including both garden pests and beneficials—so resist the urge to get rid of them! You will likely notice a resurgence of flying pests if you do.
Did You Know?
This spider is a sneaky predator. It connects itself to its web with a thin strand of silk and hides to the side. When its prey gets caught, it feels the vibrations and comes running!
These spiders' webs are strong enough to entangle both small and large prey like grasshoppers, moths and praying mantises. The females are strong and agile enough to subdue the large prey they trap. They do so by wrapping prey in silk and injecting it with paralytic venom.
Are Yellow Garden Spiders Poisonous?
Yellow garden spiders are not poisonous, but they are venomous. Their venom is toxic enough to paralyze prey, but it is extremely unlikely to adversely affect a healthy human.
In addition to paralyzing prey, the spider's venom begins to predigest the insect's insides, eventually liquefying it completely.
Note: What's the difference between "venomous" and "poisonous"? Creatures that bite or sting to inject their toxins are considered venomous, whereas those that unload their poison upon being ingested are considered poisonous.
Yellow garden spiders bite if provoked.
These spiders are not aggressive with people, but they will bite if they feel threatened. If you grab a female near her egg sac, for instance, she is likely to inject venom into you just as she would into prey caught in her web—but with a much less devastating result, of course.
For most people, yellow garden spider bites are comparable to bee stings or mosquito bites. The damage is negligible—a little itchiness, a little redness and slight swelling.
Male vs. Female Yellow Garden Spiders
Last year, I noticed three pairs of these spiders in our garden. One couple set up housekeeping in a Golden Hinoki False Cypress, another in a Miss Kim lilac bush, and another in a barberry shrub. Although I never saw the males, I knew they were there because of their webs.
Drastic Size Difference
Male Argiope aurantia are anywhere from about a third to a quarter of the size of their female counterparts, which can grow to be over an inch in size, with large, fat abdomens.
Separate Living Quarters
Not only are male Argiope aurantia much smaller than their female counterparts, but their webs are smaller, too. In fact, their webs are actually small structures positioned near or even within the larger structure of the female's web. The females' webs are large—often more than two feet in diameter. The male spiders will sometimes spin a little web near their edges.
The males live only a year and often move from female to female. Their little webs are comparable to temporary living quarters.
Other Names for Yellow Garden Spiders
black-and-yellow garden spiders
golden garden spiders
golden orb weavers
yellow garden orb weavers
yellow garden argiopes
How Big Are Yellow Garden Spiders?
Females can reach 1.1 inches in diameter (not counting their legs), and males top out at 0.35 inches (35mm).
Note: Snakes aren't the only creatures that molt. Spiders periodically shed their old exoskeletons as they grow. Don't believe it? Watch this tarantula crawl out of its old exoskeleton!
Writing spiders spin strong, distinctive webs, which can be up to two feet in diameter.
Lightning-Bolt Web Decorations (a.k.a. Stabilimenta)
Yellow garden spiders create zigzagging lines that look like lightning bolts down the middle of their webs, which is why they are often called writing spiders. These lines are called stabilimenta because they were first thought to provide structural support (stability) to the webs.
Today, scientists debate the purpose of stabilimenta. Do they attract prey? (A study published in Behavioral Ecology showed that the zigzagging lines actually reduced the number of prey captured by up to 30 percent.) Some researchers hypothesize that the purpose of stabilimenta is to deter birds from crashing into the webs. In any case, only diurnal spiders (ones that are active during the day) use stabilimenta.
Orb Weavers Have Extra Claws
Argiope aurantia are orb weavers. Like all orb-weaver spiders (there are about 180 orb-weaver species in North America alone), they are fast and prolific spinners that have three claws per foot on each of their legs. That's one more claw than most spiders have.
Orb weavers use their extra claws to help them handle the threads as they spin, allowing them to spin complicated webs in a few hours.
Did You Know?
Some spiders can make as many as seven different types of silk, though most only make four or five kinds.
They Eat Their Webs Each Night
Each night, Argiope aurantia eat the central part of their webs, leaving the anchor threads intact, and spin them anew. They do this for several reasons:
- The sticky silk that captures prey is rendered useless when coated with dust or pollen.
- Eating the old silk allows spiders to reabsorb and reuse its proteins to create new silk.
- Ingesting dew-covered silk allows spiders to take in much-needed moisture (especially before molting).
- The old silk may contain tiny insects that provide extra nutrients for the spider.
Egg Sacs and Spring Spiderlings
In late summer, female Argiope aurantia produce three or four large, papery egg sacs. Rounded and brown, the sacs look as if they're made from paper bags. Just like their webs and the spiders themselves, the sacs are large and easy to spot. This winter, even on the bleakest days, I could see their egg sacs in the shrubbery, a welcome sign of life in the otherwise barren landscape.
Each sac contains 300–1,400 eggs and can release over 1,000 spiderlings. However, only a very small of the babies survive their early spiderling-hood.
Protecting the Egg Sacs From Weather and Predators
To keep the sacs safe over the winter, the female spiders weave them into their webs. In our shrubbery, a female writing spider wove several webs for her sacs, attaching them to stems and leaves with webbing. The webbing not only holds the sacs in place, but it also provides them with protection from the elements and predators, such as ants, wasps and birds.
Yellow Garden Spider Characteristics
Description: Females sport black-topped abdomens with symmetrical stripes and patches of bright yellow. They have three-tone legs, which are usually reddish brown or orange at the base and black at the tips, with whitish-beige bands above and below one or more of the joints. Males are far smaller, with less yellow abdominal coloration and brownish legs.
When at rest on their webs, these spiders typically keep their legs in pairs, creating an X-like shape.
Range: Yellow garden spiders are common throughout the continental United States and Canada, Mexico and Central America.
Did You Know?
Spiders are found on every continent except for Antarctica!
Diet: These beneficial spiders eat all manner of flying insects, such as mosquitoes, grasshoppers, dragonflies, aphids, wasps, bees, moths, and butterflies. (On occasion, these spiders have been known to eat hummingbirds or frogs that get stuck in their webs, but this is very much the exception rather than the rule!)
Life Cycle: Males court females by plucking (and thereby vibrating) the females' webs. After mating, the female will weave between one and three egg sacs into her web. Her offspring will then hatch in late summer or autumn, though in areas with cold winters, they will remain "dormant" in the egg sac until spring.
Males usually die after mating. Females, however, tend to die in the first hard frost after mating, meaning they live for about one year (though if temperatures are very mild, females can live for several years!).
Would you welcome this spider in your yard?
- Ault, A. (2015, December 03). Ask Smithsonian: How Do Spiders Make Their Webs? Retrieved October 23, 2018.
- Blackledge, T. A., & Wenzel, J. W. (1999). Do stabilimenta in orb webs attract prey or defend spiders? Behavioral Ecology, 10(4), 372-376.
- Hawkinson, C. (n.d.). Beneficials in the Garden: Black-and-Yellow Argiope Spider. Retrieved October 23, 2018.
- McSilk, J. (2014, October 8). Joe’s Spider Of The Week: The Orb-Weavers. Retrieved October 23, 2018.
- Orb-Weaver Spiders: Facts, Prevention & Spider Control. (n.d.). Retrieved October 23, 2018.
- Yellow Garden Spider. Retrieved on October 22, 2018.
Questions & Answers
Can I safely move yellow garden spiders?
If you try to handle the yellow garden spider, it will probably bite you, so be sure to wear thick gloves, like the kind you would if pruning roses. Why do you want to move it?Helpful 56
Do Yellow Garden Spiders ever try to get inside a house?
We have lots of spiders in our house, but I've never seen a Yellow Garden Spider inside. I guess it's possible, but they're simply not as common as spiders like the American house spider.Helpful 31
If a yellow garden spider has made a nest and consequently an egg sac on my porch about 5 feet from my door. Do I need to be concerned about the babies getting into my house?
The babies will be very, very small when they emerge, and few will survive. Some could blow into your house, but it's unlikely they could harm you. Again, they will be tiny.Helpful 23
A garden spider lived on my porch all summer. I even bought bugs at the local pet store and fed her every day. She crawled to my welcome mat and died in October. She left 1 sac attached to my window screen. I have been watching the sac closely. It has warmed up to 70 today (February) in TN but it's not uncommon for it to freeze again by April. Will this affect the spiderlings? Will they make their exit too soon? I'm invested in their well-being!Helpful 4
I have bought a garden spider sac. I want to raise at least 20 babies from the sac. I saw in the hole of the sac that they are really small. My question is when will they decide to leave the sac? It looks like they molted, but they haven’t got their color yet, so they are just sitting in their sac. How long will it take them to come out?
How long probably depends on the weather there. I have never raised yellow garden spiders but understand that they remain in a dormant state until it’s warm enough for them to survive.Helpful 3
© 2014 Jill Spencer