Flying Spiders: Where They Live

Written by AZ Animals Staff
Published: May 22, 2021
Written by AZ Animals Staff
Published: May 22, 2021


Flying spiders? Yes, you read that right. If you have arachnophobia – a fear of spiders – flying spiders may sound like something out of a nightmare. Social media influencers have tried to convince viewers that flying spiders will soon be invading their backyards. What are flying spiders? Are flying spiders real? Where do flying spiders live?

What Are Flying Spiders?

Are flying spiders real? The simple answer is yes. But they’re not what Twitter and Facebook may have led you to believe.

The so-called flying spider, also called the gray cross spider or bridge spider, is scientifically classified as Larinioides sclopetarius. It is a large orb-weaver spider, meaning it spins a round web. It was first discovered in 1757.

What Do Flying Spiders Look Like?

Flying spiders are mostly brown or grey in color with dark and light markings on the abdomen. The legs are banded with brown and cream. The abdomen is large and round, while the cephalothorax or head is small in comparison.

The spider has a body length of 9mm to 14mm, and its webs are up to 70 cm in diameter. Adult spiders weigh between 38 and 60 mg, with females being nearly twice as large as males. The males typically do not spin their own webs but live in the webs of females in order to steal the prey the females caught.

Flying Spiders
Spiders use their silk as a way to disperse. A variety of spiders use their silk as a simple parachute to carry them from one place to another.

Where Do Flying Spiders Live?

Flying spiders have a Holarctic distribution, which means it lives in habitats throughout the northern continents – North America, Europe, and Asia. In North America, flying spiders are common near the Great Lakes, but can be found throughout the United States.

They are attracted to man-made objects such as buildings and bridges. This is where they get the common name “bridge spider.” They are also commonly found near water, including on boats. They have traveled via boat to many isolated islands.

Flying spider webs are often clustered around light fixtures. Lights attract prey insects, which in turn attract the spiders.

In some cities, up to 100 flying spiders may be found in a single square meter. They hide during the day and wait for prey at the center of their webs during the night. They can be found during the warmer months, from early spring through November. In America, they are most commonly seen from May to August.

In the city of Chicago, USA, residents of some high-rise buildings have been asked not to open their windows during the month of May. This is because the spiders are known to migrate via ballooning at that time. This natural cycle has been called “the Chicago Phenomenon.”

Why Are They Called Flying Spiders?

Contrary to popular belief, flying spiders are not mutant arachnids with wings. There are no spiders that have wings or that fly in the traditional sense of the word. Their name comes from a form of locomotion called ballooning. The spider releases threads of silk into the wind, using these as a “balloon” to carry the spider through the air.

The flying spider is not the only species to exhibit this behavior. You might remember the spiderlings in the classic children’s book and films Charlotte’s Web flying away on silken strands. Many crab spiders do this as well.

Do flying spiders fly around all the time? No, they do not. They spend their days hiding and their nights guarding their webs, waiting to eat any insects they catch. The spiders balloon or fly only when they need to travel to a new feeding ground. This may happen when insects become scarce in an area or when there is a lot of competition from other spiders.

Would a flying spider land on you? Probably not. The spiders are blown by the wind; they cannot control their flight. If one were to land on you, it would be a simple accident. It would likely not stay on you long. Rather, it would drop to the ground or take flight once again, still searching for an ideal home.

Are Flying Spiders Poisonous?

All spiders have venom which they use to immobilize their prey. Flying spiders, however, are not likely to bite humans, even when they exist in large numbers near human habitations. The spiders may bite if they feel threatened, for instance, if you disturb their webs or try to hold them in your hand. If you are bitten, their venom is less powerful than that of a honey bee, sometimes compared to a mosquito bite. The bites heal quickly and usually do not require medical attention.

Is There Going to Be a Flying Spider Invasion?

The simple answer to this question is no, there is not going to be an invasion of flying spiders. Flying spiders have lived in the Northern Hemisphere for untold centuries. If you happen to see a flying spider where you live, it and its ancestors have likely been there all along.

If you live in Chicago or another area that sees the “spider phenomenon,” the occurrence of spiders taking to the wind will last only a short period of time. Even when the spiders land, they will simply build webs near outdoor lights or on window sills. They will not invade your home as in a horror movie.

Flying spiders are also territorial; they are not social spiders. They may build webs beside one another, but females do not allow other females to enter their webs. This territoriality limits how many flying spiders may inhabit an area.

There are also natural predators that help control the flying spider population. A scuttle fly called Phalacrotophora epeirae feeds on the eggs of the flying spider. In southern Europe, a hunting wasp called Trypoxylon attenuatum preys on the adult spiders. It paralyzes the spider, brings it back to its nest, and lays an egg inside the spider’s body. The wasp larvae then feed on the spider after hatching.

Flying Spiders
Young spiders can move away from the place where they hatched by sending out a strand of their silk (referred to, sometimes, as gossamer) and riding it on the wind.

What Are Some Interesting Facts About Flying Spiders?

  • Each flying spider lives about one and a half years. In that time, a female spider can produce 15 sacs of eggs. Female spiders may eat the male spiders if other insect prey is scarce.
  • Flying spiders are more active than some other spiders and they like to explore new environments. This may have lead to them becoming so common in cities spread across a large area of the world.
  • Male flying spiders can biologically change into females if there are not enough females in the population. This is known as protandry.

Conclusion

Flying spiders are nothing to be afraid of. They exhibit marvelous behaviors that make them unique in the animal kingdom. If you see a flying spider or a group of them as in the “Chicago Phenomenon,” take a good look, because there is no reason to be scared.

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