Breeding Butterflies

Butterflies and moths are insects in the order Lepidoptera. They have six legs, four wings, two antennae, a head, thorax, and abdomen. Nothing brings beauty to a warm day like a swallowtail fluttering over a flower, or a group of monarchs migrating overhead.

• There are thousands of species of butterflies, and hundreds of thousands of species of moths. Butterflies fly by day and have clubbed antennae; moths fly at night and do not have clubbed antennae.

There are four stages in the life cycle of butterflies and moths—egg, larva, pupa, and adult. The most dramatic stage of the life cycle is the moment when the adult emerges from its cocoon (the pupa's protective silk covering). The butterfly's cocoon is called a chrysalis. You can breed moths and butterflies with some care. With luck you may even witness an adult female in the act of laying her eggs.

Materials

• craft sticks
• wire or plastic screen
• meterstick
• utility scissors
• needle and thread (Bottom thread works best.)
• glue
• caterpillar
• notebook and pencil
• field guides to insects and plants
• tight-fitting gloves
• small paper bag
• string
• pruning shears

A certain species of the giant silkworm moth from India, Antheraea mylitta, is one of the world's largest insects, weighing about 45g as an adult. The adult moth is bigger than your hand! An egg the size of a match head can develop into a 25-cm moth. Specimens caught in the Philippine Islands have a wingspan of 30 cm—as long as your forearm.

Procedure

Be careful when handling caterpillars. You should handle them gently. Gypsy moth caterpillars have little bristles that can cause a minor skin rash. However, you are more of a threat to the caterpillar than it is to you. Protect both yourself and your small friend by wearing tight-fitting gloves.

Some species prefer sunny locations; others do best in shade.

1. In preparation for butterfly and moth breeding, construct a small cage from craft sticks and screen. You can use wire or plastic screen. The dimensions of the cage are 20 by 20 by 40 cm. Cut the screen with utility scissors and use needle and thread to attach it to a craft stick frame. The craft sticks can be connected to one another with glue, or simply sewn to the screen for support as shown on next page.
2. Look for caterpillars in a park, meadow, or on your own property if it has trees and shrubs. Check leaves, both the tops and undersides. In particular, keep your eyes open for leaves that have bite marks indicating creatures have been munching there.
3. When you find a caterpillar, take notes on it: color, size, markings, and other distinctive information. Look your insect up in a field guide. Also, make note of the plant where it was found. You'll need to go back and take more fresh twigs from the plant later on. If you're not sure what kind of plant it is, take a sample of the leaves and stems to identify the plant later, using a field guide.
4. Put a paper bag over the twig or weed on which your specimen is feeding and tie the end closed with string so that the insect cannot escape. Cut the twig off the plant with pruning shears and bring it home.
5. Look inside the bag a day or so later. You may discover that all the leaves have been eaten. If so, shift the caterpillar to a fresh batch of the same kind of leaves and tie the paper bag over it. You may have to repeat this transfer several times.
6. Eventually you will find that your specimen has vanished and a cocoon has begun to take its place. Make note of the caterpillar's methods in building the cocoon and how long it spends in the process. When the cocoon is complete, break off the twig to which it is attached and transfer it to the small cage.
7. Place the cage outdoors in a location matching as closely as possible the site where you found the insect. After days or weeks—depending upon the species and the season of the year—the adult will emerge from the cocoon, and you will have the thrill of discovering the exotic creature your caterpillar was destined to become.
8. Release your young pet almost immediately into the wild. Its wings could become permanently damaged if it bangs them against the walls of the small cage. The best place to release your butterfly or moth is where you originally found the caterpillar. Release it in pleasant weather, perhaps on a cool, sunny morning, with no wind, to introduce your winged friend to the world on a gentle note.

References

• Butterfly and Moth (Eyewitness Books) by Paul Whalley (New York: Random Library, 1989).
• The Butterfly Book: A Kid's Guide to Attracting, Raising, and Keeping Butterflies by Kersten Hamilton (Santa Fe, N.M.: John Muir, 1997).
• Butterflies of North America: www.npwrc.usgs.gov/resource/distr/lepid/bflyusa/bflyusa.htm
• Children's butterfly site: www.mesc.usgs.gov/butterfly/butterfly.html
• Monarch Watch: www.MonarchWatch.org/
• Unraveling the Secrets of Marchs: www.sciam.com/0997issue/0997amsci.html

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