Outdoors Sustainability

Sustainability: The Great Migration

Monarch Butterflies Head to Mexico

Monarch Migration

Monarch and monarch caterpillar on milkweed. Photo by Scott Ellis

By Paula Musto

If you have a keen eye and are really lucky, you might see something truly phenomenal in our Western North Carolina skies this month—masses of monarch butterflies on their annual migration to Mexico.

Each fall, hundreds of millions of monarch butterflies migrate from the US and Canada to mountains in central Mexico where they wait out the winter. Passing through the Asheville area in September and October, these magnificent orange and black travelers can be viewed at higher elevations along the Blue Ridge Parkway.

“There are no guarantees, but if you are at the right place at the right time you may see them early in the morning as the sun comes up or evenings when they begin to roost overnight clustered on trees,” says Joyce Pearsall, a Brevard volunteer conservation specialist for Monarch Watch, a nonprofit that studies habitat and migration patterns.

The monarchs usually travel at treetop level along the mountain ridges, so they are more difficult to see in lower elevations. Pearsall says a favorite viewing spot is at Milepost 415.7, the Cherry Cove Overlook (elev. 4,327 feet).

Experts say one of the most mind-boggling things about these international travelers and their more than 2,000-mile migration is how they travel by instinct alone, passing the same mountaintops as previous generations of their ancestors did, even returning to the same fir tree forests. Exactly how they do this is largely unknown, since the migrating monarchs live only a few more months, and none make the journey more than once.

After waiting out the winter in Mexico, the monarchs begin the trip back north. En route, the females lay eggs on milkweed plants. In a few days, the eggs hatch into beautiful black, white and orange caterpillars that will transform in nine to 14 days into brilliantly colored adult butterflies.

The new generation of butterflies flies north searching out patches of milkweed plants on the way. The process will repeat over and over again, cycling through several generations as the travelers make their way to destinations as far north as Canada.

While monarchs may seem to be only pretty but insignificant insects, in reality, these creatures play a crucial role in the ecosystems they inhabit, visiting countless numbers of wildflowers each year as they seek out nutrient-rich nectar. In doing so, the monarchs transfer pollen from one plant to another and assist in those species’ reproduction, which impacts our food chain.

“They are like the canary in the coal mine,” Pearsall says. “What affects them, affects us, ultimately.” But the legendary migration pattern is at risk, threatened by habitat loss.”

Migrating monarchs are experiencing a steady decline due in large part to the increasing scarcity of milkweed, the only plant on which discriminating monarchs lay eggs. Fields where the plant was once plentiful have been plowed in recent years at a rapid pace. Along with the overuse of herbicides and genetically modified agriculture, these landscapes are devoid of the all-important milkweed. Researchers monitoring migration patterns say the population has declined more than 90 percent in the last 20 years.

One way to help the monarchs is to plant milkweed in your yard. Not only do the monarch caterpillars need the milkweed to eat but you’ll be able to enjoy seeing the butterflies return to your yard year after year to lay their eggs and feed on milkweed nectar.

And you may want to take a trip into the mountains this month to try to catch a glimpse of the traveling monarchs. “I’ve seen the migration,” says Appalachian Wild volunteer Winslow Umberger, who happened by the spectacular sight along the Blue Ridge a few years ago. “They actually flew by me as if they were on an invisible highway. It was extraordinary.”

To learn more about these iconic butterflies and the Bring Back the Monarchs campaign, visit MonarchWatch.org. Paula Musto is a writer and outreach volunteer for Appalachian Wild, a non-profit whose mission is to help injured and orphaned wildlife, to support WNC’s wildlife rehabilitation network and to provide wildlife conservation education. Learn more at AppalachianWild.org. Wish list supplies are always needed.


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