Super Spinners and
Wheels of Silk
Charlotte and her babies in the book Charlotte's Web were orb
weavers. It's easy to spot an orb weaver's web. Just look for a wheel
of silk. The pattern in each web may be slightly different, but most
of the webs are round. Orb means circle, and their round webs
explain how these weavers got their name.
Orb spiders weave beautiful, complicated webs. You usually see orb webs, like
wheels of silk, in open areas between branches or stems. But some orb weaver
webs are so huge that they stretch across small streams. Others are tiny and
tucked out of sight. No matter the web size, the purpose is the same: to trap
flies, butterflies, grasshoppers, beetles, and other food. When an insect comes
flying or hopping by, it gets tangled in the web. The spider feels the vibrations,
either by sitting in the middle of the web or on a nearby branch attached to
the web by a trap line and then she comes in to eat her prey. Tiny hairs and
slits on an orb weaver's legs and body can feel the slightest movements. These
movements let the spider know when prey smacks into the web. Like all spiders,
orb weavers have poison glands on the tips of their fangs. When they sink their
fangs into prey, the poison paralyzes their victims. Quickly they wrap their
prey in wide bands of silk and tuck them away to eat later.
Building a web is a skill these spiders are born with. They also get a lot
of practice. Lots of orb weavers rebuild their webs every night, eating up
the old line while spinning a new one. Many orb weavers can spin a web in less
than an hour. That's hard to believe when you take a close look at the webs.
Many of the lines are made stronger with several strands of silk. The spokes
and the rest of the web are non-sticky silk, but the spiral part of the web
is usually sticky.
Orb weavers have some tricky ways to stay out of sight, and webs can help them.
Some weave special designs into their webs that match patterns or colors on
their bodies. These designs offer such good camouflage that many spiders are
hard to see even when they are sitting smack in the middle of their webs. Sometimes
orb weavers stay out of sight by leaving their webs to hide in nearby leaves
or under pieces of bark.