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Sunlight & Seasons

A Spider's Life

Thousands of species of spiders exist. Each is unique, but spider lives do follow certain patterns:

Like Charlotte in CHARLOTTE'S WEB, many spiders die in autumn after producing an egg sac. But some adults live through the winter, mate in the spring, and then die, and some survive for two or more years. Large wolf spiders may live for several years, and tarantulas have lived as long as 20 years.
Most baby spiders hatch when the weather gets warm, but a few hatch from their eggs during fall or winter. It's hard to notice that they've hatched, though, because they stay quietly inside the egg sac until spring.

The first thing most kinds of spiderlings do after emerging from the egg sac is to spin a dragline and balloon away.
While spiderlings are still very tiny, they climb to a branch, fencepost, or other tall object and tilt their spinnerets up into the air. The breeze pulls silk threads out of the spinnerets. These threads form a "dragline." The spider is still very tiny and light. When the thread gets long enough, the wind suddenly plucks it up, along with the spiderling at the other end, and carries them away! This works because the spiderling is so light and its dragline long enough to give them a lot of surface area for their weight.
The average female spider's egg sac holds about 100 eggs, but some large spiders can produce a sac that holds 2,000 eggs.
Some mothers protect their egg sac until the spiderlings emerge. Some spiders attach the sac to a web, or to a plant or other structure. Some carry the egg sac wherever they go on their abdomen, and some even drag it behind them, attached to their spinnerets! (Charlotte is quite likely the only spider known to have entrusted her egg sac to a pig.)
While they are growing, baby spiders molt, or shed their skin, several times. The new, larger skin is very soft when the old skin falls off, but quickly dries and hardens to provide protection. The bigger a spider grows, the more times it must molt. Tarantulas must molt more than 20 times before they're fully grown!
All spiders eat animal food, but each kind of spider catches this food in its own way.