The road that descends into Valle de Bravo, a town deep in the mountains of central Mexico, is as steep as any. We all leaned back in our seats as the van rolled down toward the lake on which this municipality sits. But soon we were climbing back up, rounding hairpin turns on old cobblestone roads, until we came to our rental house.
Valle de Bravo is located two hours southwest of Mexico City, positioned at the intersection of several mountain ranges. It’s where millions of monarch butterflies spend each winter while their milkweed plants in the north sit under snow.
It was my 74-year-old mother’s dream to see where they wintered. She’d been trying to figure out how to make that happen for years and finally connected with an American who’d lived in Mexico for four decades (and whose house we rented). This was lucky as there is no established circuit for foreign travelers, even though busloads of tourists traverse from Mexico City to behold the creatures every weekend January through March.
This is one of the great wonders of the natural world: Each year, nearly all the monarchs in the eastern United States and Canada migrate more than 3,000 miles south, first to Texas then along the Sierra Madre Oriental mountains until they reach these peaks near Valle de Bravo, where they cover entire trees and cluster for warmth. They gather in about 14 colonies, which have numbered as high as 380 million butterflies in 1997 and as low as 14 million in 2014.
In 1980, Mexico established the Monarch Butterfly Biosphere Reserve, and in 2008, it was declared a UNESCO World Heritage Site. But despite these measures, the monarchs’ problems are far from solved. Most of the winter colonies are located in Michoacán state, where organized crime and illegal logging are serious threats. A few weeks before we arrived in Mexico last January, the director of El Rosario sanctuary was killed for trying to stop criminal logging in the area. Valle de Bravo and the sanctuary we planned to visit, Piedra Herrada, are situated in México state, which is more stable.
Besides local problems, there are global ones: Experts warn that with climate change, more powerful and erratic storms are making the gauntlet the monarchs have to run ever more challenging. Temperatures in the U.S. Midwest and South are rising. Milkweed is drying up. The narrow path these creatures fly gets narrower every year.
Nonetheless, there have been successful efforts in Michoacán to restore some of the illegally logged forests, and plans are underway to plant more drought-resistant trees. In 2019, the wintering population rebounded somewhat, with an estimated 127 million butterflies, but then that number dropped to 59 million in 2020.
Given the security risks, we were happy to stay in México state. Valle de Bravo is a picturesque town, offering paragliding, mountain biking and hiking trails cut high into the hills that overlook the lake. On our first day, the forecast called for rain, which meant the butterflies wouldn’t be flying, so we hung around town.
We were a big group — 11 altogether, including five kids and two still-ambulatory grandparents with trekking poles. We walked (slowly) to a local ceramic market, then on to the “artisan market,” a small building lined with shops selling handmade wares. As we sat in the courtyard, a lone butterfly flew among us. “Look,” my niece said. “It’s a sign we’re going to see the monarchs!”
The next day, our van came at 9 a.m. We piled in and drove up into the mountains. The road was winding. The pine trees towered a hundred feet overhead. In back, the children chattered.
“Are we in Wisconsin? It feels like we’re in Wisconsin.”
“How many monarchs do you think there will be?”
“That’s not even a number!”
We arrived at Piedra Herrada midmorning. The parking lot was covered with a layer of hail, which was melting in the sun. The air was cool. The amenities were basic, including a ticket booth, an old playground, a corral for horses, and a few open shelters, including one where women cooked cheese and mushroom quesadillas in blue corn tortillas.
We paid our 50 pesos (about $3) to get in and found a guide to lead us to the top. At first, the grandparents wanted to walk. But after five minutes — at an elevation of 10,000 feet with a mile left to go — we sent back for horses for them.
The rest of us walked. Most of the way, the trail was wide and easy. The forest near the bottom of the mountain felt like the Pacific Northwest, with moss clinging to the trunks of trees. As we climbed higher, it got drier and more open. Large hummingbirds darted among the flowers. Soon we started seeing a few butterflies. “There’s another one!” shouted one of the kids. “That’s my 13th monarch!”
Near the top, we came to a spot the horses couldn’t pass. The grandparents dismounted, and we made the steep final ascent on foot. After 20 minutes, the path flattened. The air filled with orange and black wings. Our guide paused, instructed us to whisper and cautioned “No flash” as he pointed to our cameras.
“It’s like going into a church,” my dad said. And it was. It felt like a sacred space. As we walked along the path, we were surrounded by monarchs. They covered the trees, hanging in huge clumps. Their beating wings sounded like a soft rain. We stood for a long time transfixed by this swarm of small creatures, a migration so intimately connected to our lives, to our own backyards. They’d traveled so far on such fragile wings.
Eventually the guides said it was time to go. None of us wanted to. We could have stayed on that mountaintop forever, suspended in a sea of soft wings. We knew we were witnessing something grand and rare on that hill, something we could only hope our children’s children would see.
The guides called again. More visitors were hiking up the path. The time had come. Because as these butterflies know all too well, sooner or later you must begin the long journey home.