Monarch Butterfly Migration

Iconic Communities, On the Road, Seasonal, Traditions
on April 21, 2011
Diane Guthrie

Julia Holder, 9, tries not to move a muscle as a monarch butterfly, newly emerged from its caterpillar cocoon, clings to the tip of her nose and tests its untried wings. A puff of air encourages a flutter. “That tickles!” says the girl, eyes twinkling.

Nearby, other children and adults cradle hungry caterpillars or watch with awe as more monarchs break out of their pupal sacks, unfurling their orange and black wings like a slowly expanding piece of crumpled paper. Each butterfly needs about 10 minutes for its wings to fill with fluid and an hour for its wings to harden—making the brief but grounded stage a prime time to view monarchs up close during the annual spring open house of Monarch Watch at the University of Kansas in Lawrence (pop. 80,098).

“It’s always a surprise when monarchs come out of their chrysalis,” Julia says. “It’s amazing because we don’t change forms, and they do.”

Each spring, newly emerged monarchs join several generations of butterflies that advance northward across the central and eastern United States toward Canada, setting the stage each August for a mass southward migration of hundreds of millions of monarchs across the Great Lakes and 37 states. During their fall flight, fourth-generation monarchs travel up to 2,000 miles in two months, seeking refuge from winter’s cold beneath the canopy of umbrella-like forests of central Mexico.

The extraordinary journey of the beautiful but fragile creatures is one of nature’s most phenomenal cycles. And thousands of people are working to preserve the migration thanks to Monarch Watch, an educational, scientific and conservation program launched in 1992 in Lawrence by Orley “Chip” Taylor, 73, professor of insect ecology at the University of Kansas.

Scientists have studied monarchs for more than a century but didn’t discover until 1975 that the southbound butterflies were destined for wintering grounds in Mexico.

Taylor, who had researched honeybees for two decades, turned his attention to monarchs after hearing reports of their dwindling numbers. When a colleague suggested launching a tagging program and enlisting teachers and students to help gather data, Taylor skeptically agreed. The quality of the subsequent data and the dedication of their volunteers won him over. “It was clear we’d struck gold,” he says.

Monarch Watch emerged, thanks to a growing cadre of volunteers from Canada to Mexico. From scientists to schoolchildren and from rural residents to city dwellers, they share a love for nature and an appreciation for the miraculous migration of monarch butterflies.

Science and habitat
Monarchs that survive the winter in the fir forests of Mexico fly north to Texas, seeking mates and milkweed plants on which to lay eggs. More generations follow, breeding through spring and summer and living just two to five weeks before the butterflies reach Canada. In the fall, the fourth generation completes the cycle, flying south at a pace of 25 to 30 miles per day. Some third-generation butterflies join the migration, too, and these long-distance travelers live for up to nine months.

The phenomenon involves masses of butterflies, each behaving individually, confronting the vagaries of weather and ever-changing landscape without parents or leaders to guide them, and possessing only rudimentary brains. How they manage this journey remains a mystery to humankind, but anyone who witnesses the mass migration is thankful for a glimpse at nature’s sustaining rhythms.

For Taylor, that glimpse is most pronounced in mid-October when monarchs converge in south-central Texas and follow the river bottoms between Eagle Pass and Del Rio. “It’s like a river of butterflies as far as you can see, coming right at you,” Taylor says. “It’s the most spectacular phenomenon on the planet.”

The phenomenon is in danger, however.

To survive, monarchs need milkweed—a native plant that is disappearing from farmland and along highways at a rate of 6,000 acres per day. Taylor cites widespread use of herbicides, rampant development and roadside management policies that destroy food and shelter. “We have lost 147 million acres of habitat since I started in 1992, more than three times the size of the state of Illinois,” he says.

In addition, Taylor attributes the loss of wintering habitat in Mexico to deforestation and changing weather patterns. Severe storms two winters ago claimed at least 50 percent of the insects, although this year’s mild winter helped the monarch population to begin to rebound.

As a species, the monarch does not face extinction. Populations are healthy west of the Rocky Mountains and on other parts of the planet. Losing this unique North American migration would leave a global void, however. Not only is the cycle breathtakingly beautiful, “it all feeds into this complex web of life,” Taylor says.

Heeding the call
While efforts are under way to implement a government-supported conservation plan among North American nations to restore milkweed and nectar plants for monarchs, people who value the migration have initiated their own preservation efforts.

Since its founding, Monarch Watch has developed a vast network of volunteers and spread awareness about the monarch’s migration and plight. The organization sponsors butterfly tagging programs in 37 states and five Canadian provinces. Participants also plant milkweed and nectar plants in 4,500 habitats in 44 states.

In Nashville, Tenn., Becky Collins’ kindergarteners operate a Monarch Watch station and cultivate milkweed in a small vegetable patch on the campus of David Lipscomb Elementary School.

Collins, 54, and her students raise monarchs, tag and release them, follow the fall migration on the Internet, and exchange information with other students in the United States, Mexico and Canada. In the process, the youngsters develop skills in science, math, geography, social studies, vocabulary, technology and Spanish—while also broadening their global perspectives. “They learn that what we do affects people and creatures in other parts of the world,” Collins says.

Fourth-grade teacher Tom Murphy, 56, read about Monarch Watch in 1994 and ever since has tagged monarchs on his farm near Cannon Falls, Minn. (pop. 3,795). “I feel I’m contributing to pure scientific research,” says Murphy, who tags 500 butterflies each season.

To help track the creatures’ journey, taggers attach a white, numbered patch the size of the tip of a pencil eraser to a butterfly’s wing. “Monarchs are very wonderful insects for citizen scientists like myself,” says Murphy, who believes that losing the migration would be a worrisome indicator. “The monarch migration is a bellwether to the health of our environment.”