Scientists have become increasingly concerned over habitat loss and its effect on the monarchs. Not only are their wintering grounds in Mexico at risk, but habitat loss from development, pesticide use and global warming are threatening monarchs along their migration route.

Without milkweeds along the entire route north in the spring and summer months, monarchs would not survive. Milkweeds and nectar sources are declining due to development and the widespread use of herbicides in croplands, pastures and roadsides, according to Monarch Watch.

The goal of Monarch Watch is not only to conserve and protect monarch/milkweed habitats but to create them. The project aims to create 10,000 “monarch way stations” — basically large patches of milkweed — in home gardens, schools, parks, zoos, nature centers, field margins, along roadsides, and on other unused plots of land.

“This effort won’t replace the amount of milkweed that has been lost or even keep pace with the habitat losses each year,” Monarch Watch states. “However, without a major effort to restore milkweeds to as many locations as possible, the monarch population is certain to decline to extremely low levels.”

Monarchs are the only butterflies to make such a long, two-way migration every year — roughly 3,000 miles. Amazingly, they fly in masses to the same winter roosts, often to the exact same trees. Their migration is more the type we expect from birds or whales. Otherwise solitary animals, they often cluster at night while moving ever southward. If they linger too long, they won’t be able to make the journey. Because they are cold-blooded, they are unable to fly in cold weather.

Fat, stored in their abdomens, is a critical element of their survival for the winter. The fat not only fuels their flight but must last until the next spring when they begin the flight back north. Some researchers think that Monarchs conserve their “fuel” in flight by gliding on air currents as they travel south.

For more information go to www.monarchwatch.com.