Wednesday, October 28, 2009

Persistent Spider

Cross Orbweaver (female)

The Encarta World English Dictionary defines persistence as:
  1. quality of persisting: the quality of continuing steadily despite problems or difficulties
  2. act of persisting: the action of somebody who persists with something
  3. long continuance of something: continuance of an effect after its cause has ceased or been removed
  4. ZOOLOGY resilience of organism: the ability of a living organism to resist being disturbed or being altered

The Cross Orbweaver (Araneus diadematus) living on the side of my chicken coop certainly exemplifies the definitions of persistence described above. She has continued to carefully reconstruct her web each evening along the side of the coop in hopes of capturing an unsuspecting arthropod. Her attempts to do so have been mostly fruitfull during the few mild evenings recently. And despite the rain and colder temperatures the last few nights, she continues to complete her evening ritual in hopes of a meal.

The Cross Orbweaver, also known as the Garden Orbweaver or Cross Spider, is a native of Europe but can be found throughout most of northern North America. The common name comes from the pattern of white spots on the anterior (front) of the abdomen that form the shape of a cross. Overall color patterns may vary from very light individuals to very dark individuals, though nearly all have a diagnostic "cross" on the abdomen.

Like many other orbweavers, they create intricate webs that sometimes span large distances in an attempt to capture prey. The spider is usually seen sitting face down in the middle of the web. Hungry spiders will eat their prey right away after quickly wrapping them into a bundle with their silk. Satiated spiders will wrap their catch and leave it attached to the web for later consumption.

With this species and similar species, the web is torn down and reconstructed every day. The valuable silk is not simply thrown away, but, like all things in nature, it is recycled. In this case the spider reingests its silk to save the valuable proteins and nutrients the silk contains. These ingredients will be reused for the next evening's newly reconstructed web.

I know one evening soon I won't see this pretty spider anymore. She will have accumulated enough energy through her nighttime meals to lay her eggs. Once she's completed this task, her life will soon be over. But until that time, she remains forever persistent.

-Adam Zorn, Naturalist


chuckb said...

Adam--I know most spider species are dimorphic, but what does the male look like? Does the male a. diadematyus weave a web?

Westmoreland Sanctuary said...

chuckb--From the photos I've seen, the male is a bit smaller with a much more slender appearance. Males also have enlarged pedipalps which give them the appearance of wearing boxing gloves. Males have the "cross" on their abdomen as well.