Cat-faced spider (Araneus gemmoides)
Me-ow! We’re kicking off Spooky Season with the very seasonal cat-faced spider (Araneus gemmoides).
Just a glance at the photos and it’s easy to see how they got their feline moniker. Though their binomial name is more jewel-like than cat-like. Sometimes the common name fits the bill much better than the scientific name.
These feline-shaped spiders come in a variety of colors and with abdominal patterns ranging from vibrantly lined to plain pastel. In hue they can be tan, brown, orange, red-orange or even a mossy gray-green. The key to their ID is the white “Y” shaped marking on the front of their abdomen. Often that central line, and/or its branches can be quite pale.
Cat-faced are orb weavers (or orbweavers), weaving those classic geometric Halloween webs. They are common in our area and become more noticeable this month for a few reasons: Leaves begin to fall, exposing their webs. Also, they’re maxing out their adulthood, thus reaching their maximum size (females average one-quarter of an inch, males half that at one-eighth of an inch). Finally, as the days get shorter, they tend to move their webs closer to buildings to take advantage of our artificial light to attract prey to their webs at night.
For their large size, cat-faced tend to build relatively small webs – about one foot across – though some of their web’s anchor lines may extend several feet to a convenient anchor location.
These pretty kitties will spend most of the daylight hours holed up in their hide. A hide is a covered area at the end of one of the anchor lines, this can be a crack, crevasse, or hidey-hole such as a open pipe or a rolled up leaf (see photo).
Even when in their hiding spot, cat-faced are alert and most often will have one leg on the anchor line so they’ll know if an unwary insect flies into their web. When that happens, even the chonky ladies (extra chonky in October because they are gravid, AKA chock full of eggs) move across those silken lines with surprising speed to grab their meal.
At night they will usually hang out in the center of their web upside down waiting for supper.
Cat-faced are very sedentary spiders and homebodies. You aren’t likely to ever see one running around anywhere outside of a web. They are the picture of patience 99% of the time, just waiting.
Their main activity, other than zipping over the web for a meal, is web maintenance. First thing at night, they’ll mend any small imperfections in their web, or if there’s severe damage, they’ll eat what’s left of the web (recycling at its best) then spin a new one.
This is why you rarely find an “abandoned” orb web about, waste not, want not is the orb weaver’s mantra. They’ll also chow down on their existing web before moving to a new location, and they’ll only do that if the current location isn’t serving up sufficient meals.
Like many arthropods, adult cat-faced only live one season. Females will begin laying their egg sacs this time of year and the eggs will overwinter. In a mild year, a female might lay two sacs before succumbing to winer’s chill.
The spiderlings will hatch out in early spring and scurry to find an open perch, like a leaf, branch or porch railing. They’ll each then let out a teeny bit of silk which will catch in even a light breeze and carry the spiderling off to their own personal space away from their sibs where they can spin their first web and catch their first meal. This silken flight is called “ballooning.”
In areas where food is plentiful, cat-faced kiddos will spin their webs close together, if food is scarce, they’ll spread out so there’s enough for everyone. Either way, humans reap the rewards as cat-faced are a coveted pest control species.
