The Monarch, a large black and orange butterfly, is the only butterfly in North America to fly south in autumn, overwinter in a semitropical region, and begin a return migration in the spring. Migrating Monarchs pass through the Asheville area during the latter part of September.

Monarchs do not migrate in flocks, as some of our migrating birds do, but as individuals. Each butterfly embarks on a solitary journey of up to 2000 miles to reach the wintering grounds. For individual butterflies from eastern and central North America winter home is one of several small groves of firtrees in the Sierra Madre Mountains of northeastern Mexico.

No Monarch makes the migration more than once. In fact, those Monarchs which overwinter in Mexico die early on the return trip in the spring. It is their descendants who actually return to the northern breeding grounds to lay their eggs on the fresh young leaves of emerging milkweed plants.

Caterpillars of Monarch Butterflies feed on nothing but milkweed leaves. Alkaloids contained in milkweed leaves are thought to make the caterpillars, and later the adult butterflies, distasteful if not poisonous to potential predators. This chemical protection may be important in allowing the Monarch to survive its lengthy migratory journey.

A Monarch Butterfly weighs no more than 1/20 of an ounce. Its four-inch wings are enormous relative to its body size and permit it to lift itself into the air with a seemingly casual wing flap. On a calm day a Monarch Butterfly can maintain an air speed of about seven miles per hour without overly exerting itself.

Beginning its southward journey in mid-august, the Monarch may travel only several miles per day along an erratic, meandering flight path. As the autumnal equinox approaches, the tempo increases, and on days when the wind is blowing from the north, the lightweight insect glides with the wind and may cover a distance of more than a hundred miles. On days when there is a strong southerly wind, the butterflies rest.

Throughout their journey south, the Monarchs stop frequently to feed on the nectar from a variety of wildflowers. These butterfly "feeding stations" are rewarded by having some of their pollen shaken loose onto the butterfly's body and carried to other flowers, where a few grains may be rubbed or shaken off of the insect's body to pollinate the flower.

The Monarch Butterflies passing through Asheville in mid-September probably began life as eggs laid in July in milkweed meadows of Pennsylvania, Ohio, upstate New York, and southern Canada. They have traveled about a quarter of the distance on their 2,000 mile journey to Mexico and are travelling at maximum speed.

The migrating Monarchs do not follow a specific pathway but travel individually along a broad front. During the peak of migration they may be seen anywhere, from downtown Asheville to the remote ridges of the Balsams and Craggies.

The butterflies fly at treetop level or lower, tending to cross east-west ridges at low gaps, and may be seen in greater concentration as they funnel through such natural crossing points. A good place to view Monarch Butterflies is at Wagon Road Gap at milepost 412.2 south of Mt. Pisgah on the Blue Ridge Parkway.

The Monarch watching season in this area begins with a few individuals wandering through in early September and builds to a peak, usually near the autumnal equinox, before tapering off into early October. The best time to view the migration would be after the passage of a cold front, when the weather is clear and winds are blowing gently from the north.

On such a day, when the asters and goldenrods are at their peak of bloom and the air is crisp and clear, the migrating Monarchs provide one more good reason to spend some time outdoors, enjoying our natural heritage