European Garden Spider

Last weekend while scouting rocks for International Rock Flipping Day, I noticed this young lady by my entry porch.  I snapped a couple of photos and returned to my rock hunt.  When I took another look at the photos, I realized what a beautiful creature this is.

She is a European Garden Spider (Araneus diadematus).  As the name implies, she is an immigrant from Europe and not a native North American arachnid.  Nevertheless, this has become one of the most familiar spiders seen in the Pacific Northwest.  They are most prevalent in late summer and fall.  Other common names include Diadem Spider, Cross Spider and Cross Orbweaver.

Orbweavers (family Araneidae) are the spiders that build wheel-shaped spiral webs.  The third pair of legs are specialized for building orb webs.  They are of little use out of the web.  The web is not the spider's home.  It is a trap for catching food.  This spider will build a new web early every morning.

Cropping the photo for a closer look reveals a hairy, velvety appearance.  Her abdomen is swollen with eggs which she will lay in a cocoon of yellow silk.  This particular spider lacks the characteristic cross-shape pattern of yellow spots on the abdomen.  I found her in the classic head down position in the center of the web.  She will use those third legs to sense the vibrations of a hapless insect caught in the silken strands.

One interesting behavior I have seen is making the web oscillate wildly in reaction to a threat.  This spider will bite, but references indicate that they are reclusive and difficult to provoke.  The bite is said to be slightly irritating but harmless to humans.

She is a dedicated mother devoted to protecting her eggs once they are laid.  Unable to leave them even to feed, she will die in late autumn, never seeing her offspring hatch the following spring.

To set the record straight, Rod Crawford of the Burke Museum provides a list of spider myths, misconceptions and superstitions.