The forest was blanketed in butterflies. Huge, dark green pine trees looked like oaks in fall, covered in shades of orange and yellow. The air was so thin, it hurt to breathe, and the silence was so complete, my own breathing sounded loud enough to frighten the butterflies away. Entering a world of monarchs in Michoacan, Mexico can only be described as jaw dropping. Monarch expert Dr. Lincoln Brower, Research Professor of Biology at Sweet Briar College, says the actual number of monarchs that migrate to Mexico each fall is unknown, but he estimates more than a billion make the amazing journey.
Each remote monarch sanctuary (there are four) are part of a national forest in one region of central Mexico, and each sanctuary is the wintering ground for about 50 million butterflies. Each branch of each blanketed tree can hold around five thousand of these lantern-winged beauties. Their migration, only discovered in the late seventies, has captured the imagination of people all over the globe who, like me, have traveled to see them, but due to illegal logging in Mexico and the use of pesticides and herbicides in the US, they may not live through another winter, and one of the earth’s greatest natural wonders may vanish.
Dr. Brower chose to specialize in monarch butterflies during his graduate studies at Yale University. He has since led numerous research projects in Mexico, published over two hundred scientific papers, and produced two award winning documentaries. He has literally made saving the monarch his life’s work. As one of the scientists helping to lobby for sanctuaries while teaching anyone who is willing to listen how best to protect this species, he has bought them time. Just how much time is uncertain, and with so many complex problems to hurdle, Dr. Brower continues to forge a difficult trail through increasingly dangerous terrain.
The monarchs have a complex life cycle with very specialized and specific needs for survival. Their metamorphosis from egg to caterpillar to chrysalis to butterfly is probably what first captured my interest. The monarch’s larval stage is dependent upon one type of plant, the milkweed. According to Dr. Brower, there are about 108 species of milkweeds growing in North America, and this may be why the monarchs begin their move north each March, the females spreading out in search of milkweeds where they will lay their eggs.
When the eggs hatch, the larvae will eat the milkweed until time to build their cocoons and make the transformation into the adult butterfly. The “milk” from these weeds helps protect these creatures, as the sap of most varieties is toxic to predatory species like birds. The birds then learn to avoid eating the monarchs and thereby avoid being sick. These plants also camouflage the chrysalises under its leaves until time for the butterflies to emerge, and the flowers provide nectar to the young adults while they wait for their new wings to dry.
The second generation of monarchs will continue the journey north in search of wildflower nectar and more milkweed plants to lay their eggs upon. Most likely, it is the second or even the third generation that makes an appearance in my back yard in Virginia each spring. By then, less than half way through a complete life cycle of the species, they have already faced untold perils due to our freakish obsession with weeds.
The use of pesticides and herbicides does not just kill pests. It kills all insects, even those like the butterflies that are needed to pollinate our lovely flowers. Dr. Brower says, “Millions of acres of land is basically being sterilized for commercial agriculture” alone, not to mention the damage cause by roadside, lawn, and garden sprays. When asked to speak publicly about monarchs, he implores people to remember that much of what we call weeds are the very things butterflies need to live. Spraying kills more than the weeds, it kills the wildflowers, the milkweeds, and the pollinators who keep many of our plants reproducing.
Should the monarchs survive the spraying and the destruction of habitat here in North America, every third to fifth generation, precisely on the Autumnal Equinox, will go into what Dr. Brower calls a full migration. Rather than those earlier generations which migrated shorter distances and only lived a few weeks as a butterfly, this generation will live up to nine months and carry the species all the way back to the sanctuaries in Mexico in order to survive the cold of winter. They will fly thousands of miles, sometimes within just two days of hatching.
Recent research shows the monarchs are returning to the exact colony location the first generation left during the Vernal Equinox in March. No one knows why the equinox triggers these migrations, and no one knows why the butterflies return to one exact location each winter. Research on these and other questions about the species continues.
The monarchs return to the trans volcanic range of mountains in Michoacan, mountains formed millions of years ago in the Myacine era. Their colonies are found at altitudes of ten to eleven thousand feet in a very limited area of forest where, although it does get cold in the winter, the canopy of pine trees prevents it from getting too cold and provides enough shelter to shield them from freezing. Dr. Brower says the monarchs are, “fantastic glider pilots, who take advantage of the mountain thermals.” He suspects this is why they are able to migrate such great distances without expending too much energy.
Why these particular mountains? Brower says the winds come across the area carrying moist air which condenses. The cloud formations help keep the temperature up and also allow the monarchs to drink the condensation from each other’s bodies to avoid dehydration. They cluster together in the mountain ridges against the trees, under the canopy, but far from the ground, using their bodies and the cover of the trees for warmth to survive the cold.
Unfortunately, the sanctuaries set up as national parks by the Mexican government and conservationists are in jeopardy due to illegal logging. There are several large logging operations which have already clear cut a large percentage of the forest and are irreparably harming the monarchs even as they harm their own people in the surrounding villages where tourism has become a livelihood.
Dr. Brower and his research team chartered planes to fly over the forests last winter, hoping to discover new colonies, since several of the old habitats have already been destroyed. The colonies are easily seen from the air, where dark green forests look brownish orange. What they found, instead, is most disturbing. Monarchs had returned to clear cut areas to freeze to death. Even in thinned out forests where some trees were left, they found three foot deep piles of dead butterflies. Not one single new colony was discovered. Knowing the monarchs return to the same exact locations, that they are not forming new colonies, it has become even more critical that these illegal logging operations be stopped, because the destruction of the remaining sanctuaries will mean the destruction of the monarchs.
Stopping the logging, and protecting the forests is also a complex task, due to the complex system of government in Mexico. Each region is split into numerous “Ejidos,” or communities, each having their own governing bodies and each having communal rights to the land. Some of these governments, as witnessed in recent news in the fight to stop the drug trade, are either run by or threatened by the same crime syndicates who are making their money off a variety of illegal exports. Trying to get all of these “Ejidos” to work together to stop the logging when activists like Aldo Zamora are shot by the loggers is difficult at best, and has become an increaslingly dangerous task.
In addition, according to Dr. Brower, with each decree to set aside land for conservation, illegal logging has increased. As long as consumers keep buying illegally harvested wood, the largest majority of which is used to make pulp for paper products, plywood, and particle board, tongue and groove boards, other construction products, and wood furnishings, the monarchs, the people who live near their colonies, conservationists, and a large part of the Mexican tourism industry, will remain in imminent danger.
Although the prospects seem grim, Dr. Brower says, “You have to know that you still can be a part of the solution in saving monarchs.” This is not yet a hopeless cause and there is plenty to be done right here in North America. The first order of business is to stop the use of pesticides and herbicides on your property. There are a number of ways to fight pest insects in your gardens , fields, and roadside ditches and a number of products for use which are not harmful to the butterflies.
Dr. Brower cautions that just because a product pictures a butterfly on the label does not make it a safe product. Make sure you research the products you choose. Creating butterfly gardens in your yard, or at local community parks, even at places like Lynchburg’s Old City Cemetery, can help the cause. There are plenty of online sources for more information on butterfly gardening. Dr. Brower suggests visiting Monarch Watch or The Journey North for links and information.
Writing letters to our government officials couldn’t hurt. Urge them to continue pressuring the Mexican Government towards finding more effective ways to protect its citizens and its natural resources, and to continue their President’s efforts for a zero tolerance policy on organized crime. Also, be diligent in your buying practices, particularly with regards to paper and wood products. Be willing to research products before purchasing and stop buying those which come from questionable sources. Last, but most definitely not least, as always, reduce, reuse, and recycle.
For more information on how you can help with the efforts in Mexico to protect the monarchs and their sanctuaries, visit The Monarch Butterfly Sanctuary Foundation.
Special thanks to Dr. Lincoln Brower for his ongoing efforts to save these glorious creatures and for his willingness to share knowledge and information. All photos were provided by Amanda C. Sandos.