Spooky Spider Webs!

Everyone has had that experience where you are walking along, minding your own business, when suddenly strange, gossamer threads are coating your face. You realize in a panic that you are now draped in some spider’s home and desperately try free yourself from this silky inconvenience. The very idea of this can send a shiver down your spine and may help you to sympathize with the poor bugs who never free themselves from a spider’s web. This scare factor, as well as the fact that abandoned (some might even say…haunted) houses can be filled with cobwebs and spiders, has led to the use of fake spider webs as a common Halloween decoration.

When we construct our faux-webs though, we are emulating some of the real-life ways that spiders use their spider silk. Spider silk is truly one of nature’s wonders. It is a protein based fibre that spiders synthesize themselves. Silk starts a liquid inside of the spider’s abdomen before being pulled out through their spinnerets. Typically spiders will use their legs to tug the silk out, the pressure created during the pulling hardens the silk into webbing.

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Internal spider anatomy: In the lower portion of the abdomen you will see the silk gland that leads to the spinneret (diagram by: John Henry Comstock and Ryan Wilson)

Silk is used by spiders for many applications. Some spiders will coat silk with pheromones and the lay this silk down to help attract a mate (it’s like Tinder for spiders). Baby spiders, aka spiderlings, will exude silk as a “balloon” to catch wind and be carried into new habitats. Many different species will use silk to line a burrow they live in and nearly all of them will use silk to create their egg cases. You may also see jumping spiders use silk like an anchor line. These diminutive daredevils often jump from great heights (relatively speaking at least) and use their silk as a way of not falling all the way to the ground.

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A jumping spider preparing to leap into action (Photo by: Jim Kalisch; UNL Entomology)

The most famous use though, is when spiders like orb weavers or cobweb builders construct large, sticky webs that snare food for the hungry arachnid. More primitive spiders tend to be active hunters that use speed and strength to capture food. Orb weavers, cobweb spiders, and others though use their silk as the hunting tool. Spider web construction does vary by species and we can identify four main web categories to be on the lookout for.

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Types of spider webs

Orb webs are what most people think of when they imagine a spider’s web. These tend to be large, radial nests that spiders use to catch food that flies into the web. There are circular components that are sticky and spokes that may be sticky or not. Some arachnid architects famous for this style would be barn spiders and black and yellow garden spiders. Check out this link if you would like to see how they do it!

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A barn spider in web (Photo by: Jonathan Larson)

Other styles include sheet webs, which have a silk “bed” that is suspended between long strands of silk on both sides. These webs can be quite small and may be the webs you notice dew on in your lawn in the morning. Funnel webs use a tunnel like construction to hide the spider and create an inescapable trap for food items. Grass spiders are some of the more famous builders of these webs. Finally, there are cobwebs. Cobwebs are a mess of spider silk that are hard to escape from if you get trapped. Famous cobweb weavers include the common house spider and black widows.

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Common house spider eating an ant (Photo: Jim Kalisch; UNL Entomology)

Cobwebs also tend to be what people most emulate during Halloween decorating. But now that you know all about the diversity of spider webs, perhaps with some ambition you can recreate an orb or sheet web to scare trick or treaters with!

Jonathan Larson
Nebraska Extension Entomology Educator at Nebraska Extension
Jonathan Larson is focused on providing Nebraskans with information regarding insects that may impact their lives. He can help to identify any insect or arachnid pest you find in your home or landscape and provide control tips that are environmentally and economically sustainable.
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