Four Wings and a Prayer (9 page)

What this told him was that if trees were cut down and the canopy was opened up, and it rained or snowed and the butterflies got wet, they would “lose their cryoprotection.” Big trees—that is, trees with bigger trunks—are more protective than small trees. In winter they are warmer than the ambient temperature, and they also hold their warmth even as the air temperature falls. In summer they are cooler. In both cases this explained why so many monarchs could be found clustered on tree trunks.

“That’s a complicated, nifty adaptation that’s interesting in its own right,” Brower exclaimed after describing it.

Nifty as it was, it wasn’t nifty enough to stop the illegal loggers, who were paid a premium for big, old trees. Their taking them out meant that the monarchs were losing not only their heater effect but their overhead cover as well—what Brower called their cryoprotection. But this—the cryoprotection theory—was speculative. Taking out trees was not. It produced real, hard cash.

And then it snowed. Up in the highlands in the last days of 1995, on the flanks of the Neovolcanics, the snows fell, and then they accumulated. This was unusual. More typically it stayed cold in the mountains and sometimes rained, creating the right microclimate, with sufficient moisture, for monarchs
to spend the winter without drawing down all their lipid reserves. Snow was disastrous to the monarch colonies, especially colonies sequestered in forests that had been thinned. And this was a big snow.

The reports from Mexico were dire. Butterflies were dying in numbers that were exponential. They were falling off trees, frozen. They were lying on the ground, frozen. Everything Brower had been saying for years about the dangers of cutting the oyamel trees was, sadly, coming to fruition. The forest, which had been the winter home of the monarch for ten thousand years, was suddenly no longer able to sustain it. There were reports in the
Houston Chronicle,
the
Mexico City Times,
Toronto’s
Globe and Mail,
the
New York Times.
On the D-Plex list the mood was somber. People shared what bits of information they could glean from Reuters and sources in Mexico. They were like people whose loved ones might have gone down in a crash, waiting for some kind of confirmation. And then it came. Brower and Aridjis published their article in the
New York Times.
The first line said it all: “As many as 30 million monarch butterflies—perhaps 30 percent of the North American monarch population—died after a snowstorm hit their sanctuaries in Mexico on December 30.”

Thirty million butterflies. Thirty percent of the North American monarch population. The numbers were staggering.

But then the sun came out. The snow began to melt. And millions of butterflies that had been lying on the ground began to warm up and wake from the dead. Not just millions—tens of millions. An estimated thirty million had fallen and been left for dead when the researchers first hiked in during the storm, but when they returned and the final count
was done, it was estimated that the winter storm had actually killed far fewer—about ten million butterflies. It was not an inconsiderable number, to be sure, but it was so much less than thirty million that it seemed, by comparison, negligible. Brower looked like a hysteric, the biologist who cried wolf.

Fifteen months later, here he was again, raising his voice, questioning the health of the fecund and apparently robust spring migration. This time his concern was perceived as a kind of intellectual tic, something he could not help himself from doing, and not a serious biological problem at all.

To Lincoln Brower’s studied eye, however, the numbers suggested real trouble in Mexico. As he saw it, the butterflies had left Mexico early, unable to find sufficient water and nectar because land clearing right up to the edge of the preserves had eliminated their sources.

“In February they started moving down the mountains to get closer to moisture, but instead of finding a mixed pine zone with a rich understory, they found the land cleared out,” Brower speculated. “On hot days they would be coming down in droves and there would be no place for them to spread out. With their usual staging ground for the spring migration disrupted, the monarchs simply took off and went much farther than usual.

“It’s my hypothesis,” he added, “and I can’t prove it.”

Because of their early departure, the monarchs were able to produce more generations in the north prior to the return trip—hence the unusually high numbers. To Brower, then, those numbers spoke not of health but of a decimated habitat. It had been an uncommonly mild spring, ideal for breeding monarchs. But what if it hadn’t been? What if there had been hurricanes and tornadoes and late snowfalls? What would have happened to that early generation of monarchs then?
These were the questions Brower was raising, and nobody, it seemed, wanted to answer them.

“I
REJECT
the argument that since we have starving people, we can’t save the butterflies. I totally reject that. Save the butterflies, and you improve the quality of life for those people. And they’re going to starve anyway.” More vintage Brower. It was getting on to the end of the year. The massive spring migration had turned into what appeared to be a massive fall migration, and now Brower was back in the Mexican mountains, astride an impatient brown mare, waiting to begin an ascent of Cerro Altamirano with Homero Aridjis, the poet laureate of monarchs and the coauthor, with Brower, of the much-maligned article in the
Times.
Aridjis was also on horseback, as was his wife, Betty. Aridjis had grown up in Contepec, a market town that sits at the bottom of the ten-thousand-foot mountain. As a boy, he would hike with his friends up to a field called Llano de la Mula—the “Plain of the Mule”—to picnic and watch the butterflies, which were so thick they bowed the trees. Later he convinced the president of Mexico to protect Cerro Altamirano as well as four other overwintering sites. It had been protected since 1986 because of his efforts; now he wanted to show it to his friend Brower.

The region had been experiencing a drought, and the trail up the mountain was dry and soft as ash. If dirt could be ephemeral, this dirt was, eroding one step at a time so that it disappeared as soon as you touched it. Dust rose like smoke, so much dust you could draw your name in it on the flank of your horse. The animals were walking slowly, losing their footing as the scree dropped out beneath their hooves and
rattled away, small avalanches falling behind them, loosening other rocks, making more dust. There were eleven in our party. The trail was disappearing, but we were leaving our mark.

Then the path leveled out, and we scanned the air, the trees, the ground for evidence that this was the way to the monarchs. We saw none. No butterfly wings, no dead butterflies, no butterflies overhead. The oak forest gave way to oyamel fir, and still nothing. Even the birds were still. Homero was somber. He had come to revisit the past but found instead what he imagined to be the future.

And it wasn’t just butterflies, the poet said later, when we were resting at Llano de la Mula, a slightly canted alpine meadow ringed by tall oyamel trees. This place used to be full of coyotes, skunks, and rabbits. Armadillo, too. All we were seeing now was ladybugs—thousands of them, crawling and flying in great clusters. Wrong biomass: no one was interested. Homero got up and walked around, back into the forest, looking for the clusters of butterflies he’d been expecting to find. No butterflies, but evidence everywhere of the fires that had devastated this forest fifteen years before, fires started by people attempting to clear land for agriculture, fires that had happened to get out of control. Since then the local monarch population had been smaller and less reliable, Homero said; it was perhaps a direct result of the fires, as well as of logging.

“I feel very frustrated,” he admitted, mounting his horse for the ride down. “Every time I come, there are fewer and fewer trees.”

“It is very depressing for Homero to see what has happened year after year,” Betty added. In his work she often served as his translator, but this was beyond words.

T
HE TRIP DOWN
the mountain was no less treacherous than the trip up. The horses slipped. The trail kept crumbling away till there was no trail, just dust and rocks. Homero had gone on ahead; Brower was walking and pointing out trees that had gashes in their trunks the size and shape of ax blades. There were many: it was nearly epidemic.

“These flesh wounds will invite disease,” Brower explained, “and eventually the trees will die.” When they do, they may be hauled out legally, for though it is illegal to take down living trees in this forest because it is protected by the 1986 presidential decree, there is no such injunction against moving dead or diseased timber.

Later, at about five thousand feet, we heard the sound of a chain saw, distant but distinct. A whine, a pause, a whine again. Wood cracked and a tree crashed through the understory. Half an hour farther down the mountain and there was the tree, cut in thirds and tied to the flanks of five donkeys. The donkeys were being led by two men and a boy. “How much will you get for these?” Homero Aridjis asked them.

“Fifteen pesos per donkey,” they said. Two dollars.

Chapter 4

I
T WAS DRY UP
on Cerro Altamirano, but it was dry in Contepec, too—so much so that the authorities declared a water emergency. Showers were forbidden. Flushing the toilet was not looked upon kindly. There were times of the day when tap water was not available at all. There were fires—small ones, but even so, their smoke signaled what lay ahead if the drought did not end. The forests at the edge of town had become tinder, and everyone feared they would ignite. The overwintering sites were at risk, like everything else, but the drought could not be blamed on illegal logging practices there, or on the presidential decree, or on the butterflies themselves. This was an endemic problem, a national problem, having to do with changes to the land, and with population growth, and with the vagaries of weather. So even as the land parched at ten thousand feet and the water-shed
diminished, Lincoln Brower’s hypothesis, that the butterflies were leaving the overwintering colonies early because they lacked water, remained unprovable.

This was of no consolation to Homero Aridjis, who rode back to town brooding. And neither was this: the absence of monarch butterflies at one of their traditional wintering grounds was not meaningful. No one could say that the butterflies weren’t somewhere else on Cerro Altamirano; they often changed locales from year to year. Llano de la Mula might not be the St. Tropez, the Aspen, of 1997. And no one could say that monarchs were on the mountain at all. Some years particular overwintering grounds were just not used, and this might be one of those years. But this, too, was of no consolation to Aridjis, who knew that the forests of his boyhood were changing, had changed.

E
LSEWHERE THERE WERE
reports of heavy concentrations of monarch butterflies, of air viscous with
Danaus plexippus,
places where you could not breathe with your mouth open. Sierra Chincua, near Angangueo, was one of these.

“How many?” I asked Bill Calvert, who brought me there after the conference in Morelia. We were standing on a rock outcrop watching butterflies stream past like spawning salmon. To me their numbers were incalculable, like snow-flakes in a blizzard.

Calvert didn’t hesitate. “Fifteen million,” he said.

This was our last day together. Bill had dragged his groaning, bucking truck up the steep and rutted jeep trail and stashed it in the woods. We didn’t have the necessary permits to be anything more than tourists, but out came the scale and
the ruler and the logbook anyway. The butterflies were here, and Bill Calvert was eager to know how they had fared after thousands of miles of wind and predators and rain and pesticides and spotty food supplies.

Calvert knew this place. He had spent the better part of fourteen winters camped in these woods, often living by himself in a tent, carrying out his field studies. No one had spent more time here, and even as he walked us farther off the trail, I knew he knew exactly where we were, as if the dense underbrush were macadam marked clearly with a street sign. We turned left, then right, then went straight, losing vertical feet. We were going someplace, though it all looked alike. There were monarchs overhead, clinging to the oyamel trees, and monarchs on the ground, dead. Then the trees gave way to sky and we were standing on bare rock and the sky was a river of orange and black and it was fine that we could not open our mouths because there was nothing, really, to say. After a while we moved off the rock and back through the woods to a clearing and set up shop. Bill snagged about fifty butterflies; I found a clean piece of paper and made a matrix for recording the information. We got back to work, only vaguely conscious of the foot traffic nearby. Sierra Chincua had only recently been opened to the public and was popular with American visitors. We had seen an Audubon tour group earlier in the day.