Follow That Butterfly

By Marian McNabb, Linn Grove, Iowa

Watching a majestic monarch butterfly in your garden is a thrill, but it does not compare to the excitement of tagging one—then finding out it traveled more than 1,000 miles to Mexico.

As a volunteer for Monarch Watch, I get to do just that. I help tag these amazing creatures so researchers can track their journeys and study them.

Tagging a butterfly might sound like an impossible task, but it's actually quite easy. All you need is a net and a little guidance from Monarch Watch.

This educational outreach program started at the University of Kansas in 1992 to promote monarch conservation and research. Today, it's a wide-reaching effort involving thousands of volunteers of all ages. More than 100,000 schoolchildren in 32 states and three Canadian provinces participate, tagging over 100,000 monarch butterflies each year.

"The feedback from participants has been terrific," says Program Director Chip Taylor, an entomology professor at the university. "We connect people with an absolutely magnificent natural phenomenon, and they're gratified to be able to contribute to a citizen science project."

How Do They Do It?

The annual monarch migration is one of nature's marvels. No other butterfly makes the long two-way trip—a trek of up to 3,000 miles.

From late August through September, monarchs flock en masse to warmer climates, often seeking out the same trees from one year to the next as they move south. When they reach their winter grounds, monarchs cluster together in fir trees high in the mountains. As spring returns, they begin to move north again, laying eggs on milkweed plants along the way.

Researchers hope the tagging program will help unravel a complex mystery. How do the butterflies know where to go?

"The important unanswered question is how monarchs navigate to these sites," Chip says. "The most likely explanation is that they use the Earth's magnetic field, but we don't have that pinned down yet."

Mapping the Journey

The program has yielded some other answers, however. For instance, researchers now know that monarchs east of the Rocky Mountains flock to about a dozen sites in Mexico, while those west of the Rockies head for the California coast.

"We're also discovering a lot about the timing and pace of the migration, population size and the various factors that influence the buildup and decline of the population from year to year," Chip explains.

"We're learning that many butterflies die during migration—probably more than 50%. We've never had a way of getting at this information before, but the tagging gives us a good idea."

As a volunteer, you can help answer these questions—and, if you're lucky, you'll have the satisfaction of knowing that one of "your" monarchs successfully made the journey. If your butterfly is recovered, you receive a certificate telling you when and where it was found and how far it traveled.

A monarch we tagged in Ames, Iowa in September 2000 was spotted in El Rosario, Mexico in February 2001—some 1,592 miles from where we tagged it. Another one we tagged traveled an astonishing 1,631 miles.

Stuck on Butterflies

You can become a volunteer the same way I did—by contacting Monarch Watch for a tagging kit. The packet includes tags, detailed instructions and a data sheet to return to Monarch Watch.

The tags are small, about the size of the tip of your pinky finger, with an adhesive backing that sticks without hindering the monarch's flight.

Photo: Tom Allen

"People can buy or make a simple butterfly net and then just follow the instructions," Chip says. "It's very easy to do. We've got 7-year-olds who are experts at this."

The monarchs we tagged in the fall of 2001 haven't been found—a severe storm in Mexico wiped out more than 75% of them. Monarch Watch recovered only about 2% of the butterflies tagged during that period.

"This may seem like a low recovery rate, but it's really quite extraordinary when you consider the great distances these fragile insects travel," Chip says.

We'll be tagging again this fall, and anxiously waiting for that certificate in the mail telling us our monarchs successfully made the trip.

Article originally appeared in Birds & Blooms, Aug/Sept 2002.

Additional Links

Learn How to Participate

Tagging takes place from August through October. To find out how you can get involved, log on to Monarch Watch's Web site, or call toll-free 1-888/824-4464.

You can also write to Monarch Watch, University of Kansas Department of Entomology, 1200 Sunnyside Ave., Lawrence KS 66045.