Tuesday, February 18, 2014

Admiring the monarch butterfly

I have a reader of The News to thank for my wonderful trip to visit overwintering monarch butterflies near Valle de Bravo last week. Millions of butterflies fly from the U.S. and Canada to Central Mexico every November, and fly back north in March. Modern scientists have known for less than 40 years where they stay in Mexico.
Canadian zoologist Fred Urquhart and his wife Norah searched for decades before announcing the discovery in the August 1976 issue of National Geographic. In 1952 the Urquharts had developed a tag light enough to allow monarchs to fly unencumbered. Within 20 years they had recruited 600 volunteer taggers in the U.S. and Canada. The tags pointed to a Mexican overwintering spot, but where?

A breakthrough came when the Urquharts asked readers of Mexican newspapers to help them. One reader of The News, Kenneth Brugger, set out in his camper to find the Monarchs with his wife Cathy, sending back regular reports to the Urquharts.

In January 1975 Brugger made the call the Urquharts had been waiting for. Brugger had found millions of monarchs clinging to evergreens beside a mountain clearing.

Dr. Urquhart describes his first visit to the overwintering grounds in his National Geographic article. “Then we saw them. Masses of butterflies — everywhere! In the quietness of semi-dormancy, they festooned the tree branches, they enveloped the oyamel trunks, they carpeted the ground in their tremulous legions. Other multitudes — those that now on the verge of spring had begun to feel the immemorial urge to fly north — filled the air with their sun-shot wings, shimmering against the blue mountain sky and drifting across our vision in blizzard flakes of orange and black.”

Urquhart’s article intentionally didn’t disclose the location of the butterflies but gave enough clues that the next spring I went out in search for them. At the very first place I chose, Angangueo, Michoacán, I found people who led me to the butterfly sanctuary — now the best known of them all. 

On that first visit I was free to walk between the trees where clumps of butterflies were so heavy branches drooped with their weight. The sound of thousands of butterflies beating their wings is ethereal. I’ve tried several times since then to record it; it’s never the same.

Since then a number of monarch wintering sites have been discovered in Michoacán and more recently in the state of Mexico. What the sites have in common are three things: oyamel fir trees the butterflies cling to, milkweed the caterpillars eat, and an elevation close to 9,000 feet where winter temperatures hover from just below freezing to just above. Inactivated by the chill, the monarchs burn up almost none of the reserve fat they’ll need on their northward flight.

To celebrate her birthday this month, Digs collaborator Carol Hopkins invited her brothers and sister to come to Mexico to see the butterflies. Within two hours of departing Mexico City our group was starting up the trail to the preserve near San Francisco Oxtotilco. An hour and a half later — far from the closest parking lot or food vendor — we entered a wondrous bit of forest with the tall, gray-green oyamel trees with branches drooping with the weight of butterflies.

Our delightful guide, 23 year-old Ignacio Velázquez Vera, has led groups since he was 10 and loves the monarchs. He enthusiastically taught us how to tell the difference between male and female. He gently extended the long probiscus of a butterfly to demonstrate how it allows the monarch to reach deep to drink nectar or water. Sadly, he told us that there were only half as many oyamel trees covered with butterflies this year.

This may be a topic when President Obama and Canadian Prime Minister Harper meet with President Peña Nieto tomorrow in Toluca.

Environmentalists have identified the problem as a combination of genetically modified crops in the U.S. and Canada which are displacing milkweed and illegal logging in Mexico.

A key to preserving the world’s natural treasures is making their preservation a reliable source of income for local people. The monarch butterfly reserve near Valle de Bravo is doing just that. We paid Ignacio, his mother and his sister for horse rental and guidance to the preserve.  Another family member watched our van. We paid an admission fee to the ejido on whose land the monarchs winter.

The Velázquez Vera family and the ejidatarios receive a higher income from the butterfly reserve than they would from cutting the forest and selling the lumber. Ignacio works the rest of the year in Valle de Bravo hotels but says his heart is always in the mountains.

Thanks to the new Supervia Poniente expressway, all of this is possible in a two-hour drive from southern Mexico City. The butterflies usually leave in early March so you still have time. Send me an email for detailed instructions on how to get there.

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