Visiting the Monarchs in Mexico
By Suzanne Holland, Naturalist Hidden Oaks Nature Center
Flights of fancy take many forms during the chilly days of winter. In late February two years ago, I winged my way to Mexico to witness one of the nature’s miracles, the overwintering of the eastern North American monarch butterflies. What my party and I discovered was a new, but foreboding, twist on the age-old struggle of civilization versus insect. This struggle is threatening the future of the monarch butterfly migration.
The current scientific belief is that all the monarchs east of the Rockies throughout North America migrate in late summer to an 18-by 36 square mile cloud forest region approximately 80 miles northwest of Mexico City. This area was discovered by entomologists 25 years ago when a tagged monarch from Minnesota was found among the millions of monarchs clustered on the oyamel fir trees there. Through years of international effort, five sanctuaries have been established in the region to protect the millions, if not billions, of monarch butterflies overwintering from December through early March. The El Rosario sanctuary in Angangueo opened 18 years ago and now has 10,000 visitors during the three months, mainly Mexican families on weekends and schoolchildren on weekdays. A second preserve opened five years ago, Sierra Chincua, and the third, Capulin, just opened early that year.
To travel to any of the preserves takes, well, perseverance. The oyamel fir forests are in the transvolcanic mountain range. The roadbeds are strewn with volcanic rock, and dust coats the vegetation for several feet above ground level. The drive up the steep mountain roads is to be a one-lane road into two-way traffic. Two representatives of the "ejidos," the communally owned area that is managed by the local inhabitants, hold a thin rope across the road. The offer is made to each group to forgo their own transportation, leave the driving to a native driver and enjoy the exhilarating (albeit dust-infused) view from the benches in the open-backed cattle truck.
The treacherous drive runs straight up the mountainside to the base of the sanctuary, El Rosario. The rock walkway is fronted on each side by wooden sheds, each housing a vendor of T-shirts, monarch knickknacks, or quesadillas. Our guide ushered us into a stall and swung a loose board aside.
Stepping through, we thought on first blush we had found Shangri-la. Hundreds of monarch butterflies flitted in the sunshine from mud puddle to wildflower. On closer inspection, we found that the locals use this beautiful haven as a dump. Trash competed with the flowers for monarch alighting spots!
Returning to the walkway, we found a true haven awaited us within a few hundred yards of the entrance, a basking garden. For just under ten American cents, visitors could enter a cleared area that was a sunning site for thousands of butterflies. In their efforts to warm their bodies for flight, the monarchs were densely packed on a grassy area measuring 4 feet by 10 feet. We reveled in the sight of such glorious color. Upon close inspection, we noticed more than a dozen monarchs with rosy pink patches on their forewings—mutant monarchs perhaps?
While searching the trees for life, we noticed clumps of rusty-looking Spanish moss. With the sun’s rays warming the trees, the "moss" revealed itself to be butterflies beginning to stir their fluttering wings. At first tens, then hundreds of butterflies did a free fall from the trees, only to swoop high again to their perches. The temperature was right for males to find a mate. The mating process is a lengthy one and couples tumbled in the dust at our feet. When disturbed, the male would hoist them both high into the trees while still coupled. This mating frenzy continues for a short while, for the male gives all his protein to the female and then perishes.
The clustering of the insects on the trees is reminiscent of draperies that unfurl in the heat of the sun. The site is dazzlingly bright with the orange, black, and white flecks erupting like firecrackers off the trees. Still more startling is the sound; the rush of the butterfly wings recalls a gentle summer rain as independent bunches explodes into the sky.
Sierra Chincua, a sanctuary 10 miles to the southeast of El Rosario, offers a completely different experience. Arriving on a well-maintained highway, visitors mount ponies for a 45-minute saunter up the dusty mountainside. At the summit, we left the ponies and walked down into the valley where the monarchs were just beginning to stir. The numbers were dramatically lower here, too. Typically there are three colonies, or groupings, of monarchs. This year there is only the one.
Instead of hiking around a path, we luxuriated in being able to lie on our backs at the end of the trail to see monarchs draping all around us. At mid-morning, the temperature was just right. Being at 10,000 feet is not all that leaves one breathless. New Year’s Eve at midnight was never more joyous than when the living confetti of the butterflies took flight, swooping down to feed on the nectar of the profusion of blossoms. Mating pairs abounded and the sky was dense with bright-orange wings. Just as fireworks can highlight a New Year’s celebration, the monarchs burst forth accompanied by "oohs" and "aahs" as the visitors watched various clumps expectantly, hoping to catch the first movement that preceded the muted explosion.