Naturalist Notes: Spider-Watching

Below are notes I took on the second-to-last night of our New York vacation. We spent the last few days down in lower Westchester county at my father’s house, and while playing cards that night with Obo and my step-mother I noticed this very large spider constructing her web. After we finished up the game, I stayed to watch and took notes on my observations.

7-14-12, Mam’k, NY, 9:55 PM. Waning moon.

I’m watching a large – 1.25″ – spider in her web outside a large bay window. The window gives me a great vantage of my subject – I can get right up close to her and observe her actions, while still having a pane of glass between us. Obo took some pictures of her from outside (below). She has a large and heavy abdomen, gray and fuzzy with long, slender legs that are banded brown, white and black.  Her web is over 18″ in diameter, orb-weaver type.

I watched her building her web for over 50 minutes. How often does she do this task? The amount of energy needed to both produce the thread and create the web itself must be considerable. Is it a nightly activity? [note: web was gone the following morning; my resource (see below) says they build at night, but not whether it’s every night; I suspect that it is.] I know so little about spiders. Their lives are pretty short, but she’s a biggie. Is she longer lived than the average cellar-dweller types I find in our house? They only seem to live for a week or two at most once they appear [Yes, spiders live in my house unmolested. I follow the belief that it’s bad luck to kill them, and besides, the service they provide – eating the flying things that make their way in – is a plus.].

How fast she is! To get to a lower section of web, she throws a line out and sails down. But she’s no slower coming back up – all eight legs flying.

There’s a larger (than the few already caught) insect causing havoc to the web as it bounces off the window. The spider scuttles [is there any better word for how spiders move?] to the center where she waits out the movement.  She’s caught it! Her legs move almost too fast to see as she wraps up this big new catch. I am simply amazed at her speed – ferocious, it seems. She is definitely a fearsome predator.

A moth, eyes glowing orange in the reflected light of the lamp, lands on the window. It is big enough to destroy the well-made web, but it deftly avoids getting snared as it first lands on, then flies away from the window.

I can’t tell what her newest catch is. She didn’t wrap it up completely, as she did the smaller ones – only enough to immobilize it. It is nearly Japanese Beetle in size and shape, a bit smaller.

I’ve been watching her feed on her second catch (not the beetle) for a while now. It landed to the right of center on the web, and she wrapped it up and left it there while finishing the construction of her web. When that was finished, she brought her prey to the center of the web and began consuming it. At some point I believe she removed the thread that it was encased in, and it became a black, glistening mass in her pincers. How much of their prey do spiders consume? Does it differ with different species? I had the impression that spiders only drained them of their internal fluids, but the size and shame of her prey has changed while I’ve watched; its shrunken and collapsed. It’s nearly gone now, I can’t even tell if there’s anything there, or if I’m looking at a part of her underbelly. No, it’s gone now – did she really consume the whole thing? That would explain the removing of the thread when she began (if that’s what she did).

Now she appears to be cleaning her front legs. It’s a delicate and almost cat-like movement; she uses her front pincers to help.

Web-building and feeding are done and she rests now, hanging upside down in the center of her web, motionless. She is a fascinating, beautiful and frightful marvel of nature.

Obo caught this picture of me watching the spider as he was trying to photograph it from outside.