Small communities in rural Mexico join together to restore Monarch Butterfly habitat.

Photos and story by Sue Sill, PhD

Monarchs like these spend their winters in the oyamel forests of Mexico.

When they migrate south, monarch butterflies travel up to 2,500 miles from the north-central and northeastern United States and southeastern Canada to Mexico to spend the winter on forested mountaintops in the state of Michoacán. There they spend the cold months amid the boughs of oyamel fir trees, hanging in bunches so large and dense that the branches bend under their weight. It is estimated that hundreds of millions of butterflies arrive on these mountaintops each winter. This amazing natural phenomenon draws thousands of tourists from around the world, who flock to the sanctuaries when the butterflies are present. As each butterfly huddles in the warmth of its neighbors for protection against the chill of 10,000 feet of elevation, their clusters resemble little more than dead leaves on the branch. However, when a ray of sunlight breaks through the clouds and warms them, millions of butterflies take to the air and a gentle rustling sound can be heard – the beating of millions of tiny wings.

No one knows for sure how long the butterflies have been coming to these mountaintops, or how long indigenous people have lived in their midst. What we do know is that the butterflies have influenced the culture of these people for centuries, as evidenced by the myths and folklore that surround them. The monarchs arrive on or near November 2, when Dia de los Muertos (The Day of the Dead, known as All Souls Day by Christians in the US) is celebrated across Mexico as a time to remember loved ones who have passed on. Because the two events have coincided for so long, many in these mountains believe that the butterflies carry with them the returning souls of their ancestors.

In the cold mountain air, the monarchs huddle together in the trees for warmth.

Although monarchs stream across the US each fall as they head to Mexico, it wasn’t until the winter of 1975-76 that their final destination became known to the outside world. That’s when Canadian scientists Fred and Norah Urquart discovered over-wintering colonies near Zitacuaro, Michoacán.

Since the discovery of the monarch’s winter home, scientists have focused greater effort on trying to understand these amazing insects and their unique migration, which takes two to three generations to reach the limits of their journey north but only one to return south. This means that the butterflies heading to Mexico each fall are new generations that have actually never been there. How they find their way is a mystery that science has so far been unable to unravel.

The unique migration of North American monarchs is gravely threatened by loss of habitat across all of its range, which includes the U.S. and southern Canada. The forested mountains of Michoacán, the place the insects are most vulnerable, is absolutely key to their survival. Only there is the entire North American population compressed into a small geographic area for four to five months. In 1986 the Mexican government established the Monarch Biosphere Reserve, a protected area of nearly 140,000 acres, in an attempt to maintain the habitat. However, illegal logging in the area continues, claiming more acres of forest in and around the reserve every year.

The La Cruz Habitat Protection Project grew out of one man’s frustration with the rampant deforestation in the over-wintering grounds of monarch butterflies. Loss of forest was putting the entire annual monarch migration phenomenon at risk. And not only was it continuing unabated; it was accelerating.

Jose Alvarez works in his tree nursery to ensure a steady supply of trees for LCHPP’s reforestation efforts.

In 1996 a Mexican tree nurseryman by the name of Jose Luis Alvarez Alcala was growing seedlings for the Mexican government’s reforestation efforts. “It was heartbreaking to see how fast the forest was being cut down, and how few trees were being planted to replace it,” he confides. Yet he had an idea that if he could find the financial support to produce large numbers of tree seedlings to give away, he could convince local farmers and other members of rural communities to plant them on portions of their land. This would get more trees in the ground, and would also provide impoverished communities with their own forests from which to harvest wood.

The forest people who live among the butterflies eke out a living from what they are able to harvest. They need firewood for cooking and heating as well as building houses and fences. Sometimes they also sell wood to provide a much-needed source of income. If new forests could be planted on the denuded mountainsides in the buffer zone of the biosphere reserve, the trees could be legally managed for economic needs. This approach to community forestry takes pressure off the existing forests as a source of wood for the rapidly growing human population that lives in the shadow of the monarchs, and also has the potential to help those people out of the cycle of poverty. The new forests are managed in such a way that they can be sustained for generation after generation.

Cerro Altamiro is the site of one of the La Cruz Habitat Protection Project’s many reforestation efforts.

The increased forest cover in and around the sanctuaries helps to restore the climate for the butterflies and maintain the water balance in mountain springs, which are critical water sources for all life in the area. Trees inside the core zone of the reserve cannot be legally cut, but people in the communities are often willing to donate time and energy in planting trees there. This is no small sacrifice for these families and individuals, but they do this because they understand that it makes their region a safer habitat for butterflies and humans alike. Reforesting bare slopes can prevent erosion, which in turn prevents natural disasters such as landslides. Reforestation also helps restore the land’s hydrology; within a few years after adjacent slopes had been planted, previously dried and degraded springs begin to flow again.

In 1997 Alvarez, having turned his efforts into the official La Cruz Habitat Protection Project (LCHPP), and using funds from a donation made by Robert L. Small, convinced four families from Ejido El Rosario to donate their time and labor and dedicate a portion of their limited parcels of land to growing forest trees instead of corn or oats. As a result, 7,000 new trees were planted that first year on over eight acres of land. The following year 40,000 seedlings were given to 20 more families that Alvarez was able to convince. The funds for this undertaking came from the efforts of Robert Small, D.J. Agnew, and Ed Rashin, who organized the Michoacán Restoration Fund. From there, the project continued to grow. In 2007 the project’s territory was expanded into new and important areas of the monarch region. These include the slopes of Cerro Altamirano in the northernmost part of the reserve, and the site of the previously destroyed El Cedral monarch colony near Tlalpuhahua. The El Cedral colony had been part of the original reserve but was denounced when its forests were lost to wildfires, pine beetles, and logging, and the butterflies stopped returning there. With the progress the project has made in the region, monarchs have slowly begun to return to nearby reforested regions, nestling in the much younger oyamel firs. This development gives hope that the entire colony will return if the forest is fully restored.

With encouragement and support from the October Hill Foundation, Alvarez was recently able to initiate a long-held plan to expand LCHPP’s reforestation efforts to include the watersheds of two important highland lakes. The expansion began in 2008 with the planting of 100,000 trees around the watersheds of Lake Patzcuaro and Lake Zirahuen. Pollution from development and agricultural chemicals has tainted one lake and threatens the other, as each rainfall brings the pollutants running down the nearby mountainsides. Planting trees on mountainsides reduces runoff and would ensure that fewer contaminants end up in the lakes.

Enthusiastic volunteers plant trees with LCHPP.

In 2008 Alvarez and his supporters managed to get 740,000 trees planted, bringing the project’s total tree count to roughly 4 million. None of this could have been accomplished without generous support from the October Hill Foundation, U.S. Fish and Wildlife Service, National Fish and Wildlife Foundation, Reforestámos Mexico, and numerous other organizations. American Forests’ Global ReLeaf program, which has planted millions of trees in deforested areas around the world, has sponsored the planting of 350,000 trees.

Those wishing to help restore Michoacán forests for the monarchs, or to save the highland lakes, can do so through American Forests. Every dollar plants a tree that contributes to clean water and air, stable landscapes, and a habitat for creatures like the beautiful monarch butterfly.

Sue Sill, Ph.D. is the Executive Director of La Cruz Habitat Protection Project, Inc.

This article was published in the Winter 2009 issue of American Forests magazine.