A Monarch Miracle

What a difference a year can make! Last winter, monarch butterflies died off in record numbers. This year, researchers are reporting that these delicate creatures have made an impressive comeback. The healthy number of monarchs has many scientists puzzled. “It's amazing that they recovered so well,” said butterfly expert Bill Calvert.

On the Rebound

In January 2002, a severe storm killed millions of monarchs that were spending the winter in Mexico. After the unusual winter storm, the monarch colonies, or groups, covered only about 5 acres of forests in Mexico. Between 1993 to 2001, they had covered an average of 24 acres.

The data collected in 2003 showed that monarch colonies, or groups, covered about 20 acres of forests in Mexico. “The data this winter indicates that the monarchs are moving back toward their average population size,” said Lincoln Brower, another butterfly expert.

Each fall, millions of monarchs migrate, or move, south from the United States and Canada to their winter homes in the mountains of Mexico. The orange-and-black monarch butterflies return to the United States and Canada in the spring.

A Disaster in the Making

Butterfly experts and the Mexican government are concerned that illegal logging is destroying the monarchs' habitat, or home. Cutting down trees thins one of the top layers of the forest, called the canopy. Without the canopy, monarchs are exposed to cold, wet weather, which can kill them.

Government officials in Mexico are working with environmental groups to stop illegal logging and save the forests and the monarch butterflies.