Last week we learned the fate of spiders that had paralyzing encounters with mud dauber wasps. This week we meet one of the local giants of the spider world, the spotted orbweaver. Late summer is a time when many spiders reach maturity and maximum size, having devoured prey throughout the growing season. At the far end of my front porch, a rapid chill on a humid night spawned condensation perfect for decorating the threads of an orbweaver’s web. This web was no tiny affair like webs of cellar spiders or common house spiders we met in previous episodes. This web spanned almost two feet and was the handiwork of the spotted orbweaver.
During the day, my orbweaver hides in a silken redoubt beneath the eaves, but at sunrise she can be found feasting on unidentified morsels or tidying up her web.
In nature the spotted orbweaver is a denizen of woodlands, where it builds its web amongst the twigs and branches of trees and shrubs. Interesting studies of their web placement revealed that these spiders are creatures of the light. Webs are strung in relatively well lighted areas where the density of flying prey may be greater. This scenario surely fits with the location of my spider’s web, cleverly constructed in a light gap between shrubs on the southern exposure of my porch. During the daytime, the orbweaver hides in a small silken refuge attached to the overhang of my porch. At night, after constructing a new web, it hangs head down in the center of the web awaiting hapless victims to entangle themselves. Once the victim is snared, powerful chelicerae are used to pulverize prey. The protein in these morsels is turned into to as many as a thousand eggs deposited in a spherical egg sac placed near the web.
Watch as this orbweaver wraps its prey and delivers paralyzing bites to the victim.
Now that this magnificent spider has set up shop on the front porch, I can’t wait to see what she captures and how she eventually turns these meals into an awesome egg sac.
The wonderful website “Neoscona crucifera (Spotted Orbweaver)” at www.spiders.us and the article “Choosing Hunting Sites: Web Site Preferences of the Orb Weaver Spider, Neoscona crucifera, Relative to Light Cues” by M. R. Adams were used as references for this episode. The inspiration for this episode came from several Maryland Master Naturalists enamored with large spiders they had recently observed.