These little guys were all balled up in a labyrinth of silk runners stretched between two stems of a young elephant garlic we keep in a pot on the deck. That was this morning. I just checked on them tonight (about 10 PM) and they were making a break for it. I suspect many of them will have vanished come daylight, and the rest will follow sometime during the day. If I have my facts straight, they climb to a high spot, one by one, turn their little rears towards the sky, and shoot out a long filament of silk. When the wind catches it, they let go of whatever they are perched upon and set sail for their permanent home.
If you disturb them while they are still balled up and waiting for the right moment to make their break, they’ll spread out from the center until they are more or less uniformly distributed within the maze of webbing they create as part of their day-to-day work. But within a few minutes they’ll be huddled back into a tight, spherical huddle.
I think they are crab spiders, but am still working on an absolute ID. When I contemplate their method of moving from place to place I am invariably reminded of a Zen parable about a man who falls into a fast running river and can't swim. He grabs hold of a rock, but the current is so strong the water keeps pushing him under the surface. He will drown for sure if he holds on to the rock, but he is too afraid of the river to let go. The spiders appear to have no such dilemma; but who can say for sure?