7 September 2013

Monday macrobug: Colonial spiders at the Fort Valley Library

Posted by Callan Bentley

I volunteer on Wednesdays at the Fort Valley Public Library. We have some bushes out front, and in the past month, I’ve noticed something about the bush closest to the library door…


It’s having some trouble, and the trouble seems to be coming from… (( brace yourself )) … a colony of spiders!


You’re seeing a single giant dense web there, occupied by many many individual spiders, and full of debris – dead insects, dead leaves, etc.


A close-up of the affected leaves:


And, for comparison, the healthy, non-arachnid-colonized bush next to it:


Sheltering amid the leafy debris are the web-spinners themselves… Creepy little tangle-web spiders (my least favorite variety of spider; family Theridiidae ). Here’s a little spider crew, with a few individuals straying from the protection of a suspended blade of grass:


Here’s my hand for a sense of scale:





I’m a lifelong arachnophobe; while I love the role spiders play in the ecosystem, and even enjoy the company of certain spiders (like the cute little jumping spiders, which seem to me like puppies with extra legs), I can’t stand tangle-web spiders. Their form totally creeps me out. It’s an instinctual response, rather than an intellectually-informed consideration. Viscerally, I cringe and squeak when I encounter one unexpectedly.

In the interest of landscaping, the library management may choose to eradicate this colony. We’ll see. For the moment, I think it’s the only example of colonial spiders I’ve seen on the North American continent. I’ve seen them in southeast Asia and Australia, and I think Costa Rica, too, but right here in my little valley? It’s new to me.