Camera: Canon EOS 550D – Location: My bathroom court-yard garden, Tarlton, Gauteng, South Africa
The spider’s touch, how exquisitely fine!
Feels at each thread, and lives along the line.
I was SO excited when I discovered an Orb-web spiderling, just 3cm from the tip of her front legs to the tips of the hind legs, in my garden! She had just anchored her lines between a Cape Reed Grass spike and the one pillar of the patio when I took the picture and when I returned half an hour later, she had started on her wheel, complete with the typical thick zig-zag lines in the center. The colours on her back are amazing and reminiscent of an Indian totem pole! You can see the colours on her back here
During the process of making an orb web, the spider will use its own body for measurements.
Many webs span gaps between objects which the spider could not cross by crawling. This is done by letting out a first fine adhesive thread to drift on the faintest breeze across a gap. When it sticks to a suitable surface at the far end, the spider will carefully walk along it and strengthen it with a second thread. This process is repeated until the thread is strong enough to support the rest of the web.
After strengthening the first thread, the spider will continue to make a Y-shaped netting. The first three radials of the web are now constructed. (the “Y”-thread can be seen in the pic below by her hind legs). More radials are added, making sure that the distance between each radial is small enough to cross. This means that the number of radials in a web directly depends on the size of the spider plus the size of the web.
Many orb-weavers build a new web each day. I have often watched this process. Generally, towards evening, the spider will consume the old web, rest for approximately an hour, then spin a new web in the same general location. Thus, the webs of orb-weavers are generally free of the accumulation of detritus common to other species such as black widow spiders.