Monarchs, Migration and Tiny Tags

Sue Halpern
Kids' Fall 2009

Wander through Ontario’s Presquile Park any fall day and chances are you’ll see monarch butterflies – lots of them. Presquile is a launching pad for nature’s most intrepid insect: from here the monarchs will fly nearly three thousand miles in about six weeks, logging up to 200 miles a day, to get to their overwintering site in the Transvolcanic Mountains of Mexico. They will have to evade hawks and other predators, dodge cars, and cope with a changing landscape that has ever less water to drink and fewer flowers for fuel, as farmer’s fields in the Midwest are plowed under and paved over, as highway median strips throughout the east are mowed, as the oyemel forests in the Mexican mountains that offer cover from
winter rain and snow are cut down for fuel, and as the demand for water, coupled with drought, drain the aquifers upon which we all rely. Though monarchs are one of the most abundant butterflies in the world, this shrinking habitat has led scientists to declare their unprecedented, long-distance migration, an “endangered phenomenon.”

But not if Don Davis can help it. Davis is an unassuming, compact, middle-aged man who is almost as likely as a monarch to be found in Presquile Park. If the monarch is the king of butterflies, Davis is its most loyal liege. For the past forty years, since he was a seventeen-year-old high school student working on a science fair project, Davis has been tagging monarchs, raising monarchs, educating the public about monarchs, and advising the governments of three countries about monarchs – and he’s not even a scientist. Not in the traditional sense, anyway. By day, and sometimes by night, Davis makes his living as a social worker – at one time he ran a facility for juvenile offenders. But he has made his life on the shore of Lake Ontario, net in hand.

In 1968, when Davis began volunteering with Toronto naturalists Fred and Norah Urquhart, no one knew much about the monarch’s remarkable journey. The Urquharts developed a tiny tag with identifying information that could be glued to a monarch’s forewing, which they gave to Davis and a few others. Pretty soon, people in the United States began to find these tagged butterflies and before long patterns started to emerge: the monarchs were traveling south, through farmers’ fields, along highway median strips, and hugging the Atlantic coast, typically covering forty miles a day. It would be a decade, though, before anyone figured out where exactly they were going, when a monarch tagged in Minnesota was recovered in the mountains northwest of Mexico City by another Urquhart volunteer (who, when he wasn’t chasing butterflies, worked in an underwear factory).

Ten years after that, a monarch tagged by Don Davis in September was found flying around Texas in April. It had been alive for at least six months, maybe longer, and earned both Don and the butterfly a place in Guinness World Records. Since then, more of “his” butterflies have been recovered, both in Mexico and along the flyways, than those of any other “citizen-scientist.” This may have something to do with sheer numbers: no one person in the world has tagged more monarchs – something like 30,000 – than Don Davis.

These days, Don Davis tags butterflies as a way to introduce people to the wonders of monarch migration, and to the threats posed to it by overdevelopment in the United States and Canada, and by logging in the Mexican mountains. He encourages them to create monarch “way-stations” by planting gardens where migrating butterflies can stop to nectar. “This doesn’t just benefit monarchs,” he tells the people who stop by his display in Presquile Park. “It helps other pollinators as well.” Davis hands out tags from Monarch Watch at the University of Kansas and demonstrates how best to put them on a butterfly’s wing. “You do this,” he tells people, “and you can make a meaningful contribution to science.” He should know.

About the Author

Sue Halpern is the author of Four Wings and a Prayer: Caught in the Mystery of the Monarch Butterfly and four other books.