Orb Weaving Spiders and Their Webs
Opell Lab, Department of Biological Sciences, College of Science, Virginia Tech
The Opell Lab in the Virginia Tech Department of Biological Sciences studies the adhesive prey capture threads of spider orb webs. We are learning how the thread’s hygroscopic glue droplets respond to differences in environmental humidity and how differences adapt species to habitats with different humidity regimes. This requires us to characterize the material properties of the viscoelastic, adhesive glycoprotein core at the center of each droplet and to understand how the adhesive forces of multiple droplets are summed to generate an efficient adhesive delivery system.
The intricate orb webs that are common during late summer allow these spiders to capture their insect prey.
Spider orb webs are common sights in the late summer and early fall when these spiders mature and place their webs higher in vegetation. The services that orb weaving spiders provide may not be as obvious as those of other arthropods like honeybees that pollinate crops and produce honey. However, orb weaving spiders contribute to the 400 – 800 million tons of mostly insect prey captured annually by all spiders. Our booth describes spider anatomy, shows how orb webs are built, identifies the features of these web and the decorations that some spiders add to their webs, and explains what makes orb webs sticky so that they can hold prey. Over 4,700 species of orb weaving spiders have been described, but it isn’t difficult to become familiar with the most common species that are found in Virginia. We provide a guide to 15 of these species organized by the habitats in which they are found.
Spider Anatomy
This page explains the parts of a spider's body and their functions.
Web Building and Features
This page explains the parts of a spider orb web and how a spider builds an orb web.
Why Are Orb Webs Sticky?
This page explains what makes the capture threads of orb webs sticky so they can keep insects from escaping until a spider can wrap or bite them and begin feeding.
Web Decorations
This page shows several kinds of decorations that some orb weaving spiders add to their webs and explains the functions of these decorations.
Common Orb Weaving Spiders of Virginia
This guide shows 15 orb weaving spider species that are commonly found in different habitats.