The dead butterflies came up to his ankles, an ocean of orange and black that extended as far as he could see.
On a mountaintop in central Mexico, Bill Toone stepped lightly. He had helped save the California condor. He had protected species around the world. But he was not prepared for this. The piles of monarch butterflies -- estimates would put the figure at 250 million dead -- were so thick that they were composting at the bottom.
The butterflies in El Rosario sanctuary froze to death that winter of 2002, victims of a cold brought on not only by the vagaries of weather but also, Toone says, by illegal logging that is systematically destroying their habitat.
The forest acts like a blanket, protecting the butterflies from extremes in temperature. Without it, they freeze.
But the forest, like the butterflies, is disappearing. More than a thousand acres were cut in the butterfly sanctuary last year, and in the last decade the number of monarchs migrating to Mexico declined from 900 million to 340 million, according to scientists and the World Wildlife Fund.
The butterfly is a harbinger of larger human troubles facing rural communities in the mountains of central Mexico: extreme poverty, scarce water, few jobs. The loss of the forest, and the monarchs, also could mean the end for these communities. The forest traps moisture and releases it into canals built along the mountainsides. The communities use the water for cooking, washing, drinking and irrigating crops.
There is no other source of water. As deforestation has accelerated, communities have seen their water supply cut by at least half. Canals that once gushed now trickle.
"There's this realization that the end is in sight," says Toone, a 51-year-old conservationist from San Diego. "There's only so much land they own, and they're watching it go empty. This can't go on forever."
Several of the communities that make up the Monarch Butterfly Biosphere Reserve, a rugged 139,000-acre sanctuary, are not waiting for the government's help. They are arming themselves, forming patrols and confronting the loggers.
On a bright morning this spring, Vincente Guzman Reyes gathered his horses and his guns. He packed soda bottles, tortillas, meat and vegetables into a bag. He tucked a 9mm under the waistband of his jeans. Then he climbed onto his horse and set off into the forest.
Every man older than 18 in his community, Donacio Ejido in the central Mexican state of Michoacan, is required to participate in the patrols. They are not paid. Several times a year, each man goes up the mountain in a group of seven. For 30 hours, they watch over their 3,000 acres -- looking for tire tracks, for cuts in the barbed-wire fence that marks their land, for any sign of logging.
"If we stopped patrolling for a day or two, nothing would happen," Guzman says. "But if we stopped for a week, 100 trees would be gone."
A few years ago, because of a miscommunication, the forest wasn't patrolled for three days. In that time, an area the size of a football field was clear-cut.
One night on patrol this spring, the buzz of a chain saw pierced the air. Guzman and six other men were warming themselves around a campfire, telling ghost stories. (One man insisted that if you point a gun at a coyote, it won't fire.) But at the faint sound of the saw, the storytelling stopped and the men listened.
"It's too far," Guzman said finally, meaning whoever was cutting trees in the dark was not cutting their trees. There was nothing the men could do.
The lure of logging is easy to see. In the mountainous region between Mexico City and the Pacific, jobs are scarce. Some people grow avocados, mangoes and corn, but the cost of getting the produce to market makes it almost impossible to turn a profit.
The tall fir and pine trees are more valuable and, at one time, were plentiful. But many mountainsides are now bare. From the road, they look naked and exposed against the blue sky. Communities sell their trees to paper companies, but also use them to build homes and for firewood. In the butterfly reserve, 100,000 trees are cut every year for personal use.
The World Wildlife Fund reports that 183 acres were deforested in the reserve in 2001. That figure rose to 1,139 acres last year. In the last six years -- the only period for which there is data -- more than 3,000 acres of the reserve's 33,000-acre core zone were lost to logging.
The loggers have become more aggressive, moving onto protected lands as other areas are clear-cut, and bribing officials to gain access and escape punishment, according to Toone and other advocates.
Other communities are following Donacio Ejido's lead. They have planted thousands of trees. Several have begun patrols of their own, and at night the patrols from each community greet each other with a shotgun blast. Partly because of this vigilance, the acres of trees lost to logging fell to 603 for the last 12-month period.
Toone also has helped, using his San Diego-based EcoLife Foundation to organize the communities to protest en masse. He has distributed efficient stoves that require less wood than traditional ones. Some communities at first distrusted outsiders, and some of the 200 stoves that were distributed were vandalized.
But now, Toone says, communities welcome the help.
"Every time a forest is cut to completion or a monarch butterfly colony disappears," he says, "it's a job that ends. And it means that fathers will leave their families and children to make money somewhere else."
Lincoln P. Brower remembers the first time he came upon a monarch colony in Mexico. It was 1977, and Brower had been studying the butterfly for two decades. When he learned that millions of them clustered together each winter in these mountains, he went to see for himself.
In 1974, a U.S. businessman in Mexico read about butterflies sighted in the nearby mountains and passed word along to National Geographic magazine, which sent a reporter. The story ran in August 1976, and scientists finally learned where the monarchs spend the winter.
"You just couldn't believe it," Brower says, describing the thick clouds of butterflies he encountered on his first trip. When the sun warmed them during the day, they would alight from the trees, the cumulative sound of their beating wings creating an audible buzz. "It was just the most incredible, amazing thing I had ever seen."
But to get to that colony, he had to drive up a logging road. Even then, 30 years ago, he could see that the forest was disappearing. Brower, now 75 and a professor at Sweet Briar College in Virginia, had been fascinated by the monarch's migratory pattern.
A complete migration -- from southern Canada and the northern United States to the central Mexico sanctuary and back -- takes three or four generations of butterflies. One of these is a "super-generation" that lives seven months -- five times longer than the other generations -- and travels 2,800 miles on the strength of its five-inch wingspan.
"There's nothing like it anywhere in the world," Brower says. "Unlike birds, the monarch is going back to the same exact spot, as if there's some kind of computer program in their brain."
But that amazing ability to return to the same place each year also may doom the butterflies, because those places have fewer and fewer trees.
"And then," Brower says, "they freeze."
He lobbied the Mexican government to protect the butterflies, and in 1986 a presidential decree created the butterfly reserve, an area about the size of Chicago. In 2000, Brower helped revise the plan to protect the reserve. But he said enforcement had been lax.
"I frankly think the Mexican government has proven themselves over 30 years of not being able to protect these butterflies," he says.
The country's forestry police is stretched thin and susceptible to bribes, say local officials.
The locations of checkpoints to stop logging trucks are widely known and easily evaded.
The army is busy fighting the drug cartels.
The butterflies suffered two major die-offs in recent years -- in 2002, when 250 million froze, and two years later, when more than 100 million froze.
Brower said a perfect storm of events -- a poor migration year in the U.S., followed by a cold winter in Mexico and then dry weather for the migration back north -- could wipe out the monarchs entirely.
A lifetime in conservation has taken Bill Toone from Antarctica to Paraguay to Papua New Guinea. He helped develop and run the San Diego Zoo's California condor recovery program, collecting eggs in the field and raising condors in captivity.
Ultimately, he says, he realized that his work had to be about more than protecting animals and resources.
"Conservation is about nothing," he says, "if it's not about people in the end."
In Escovales, a few mountaintops away from Guzman's community, the swarms of butterflies are gone. Loggers took thousands of trees from this community in the last 15 years, without paying or asking permission.
"There is no forest," says Alejandro Salgado Flores, 48, "and there are no butterflies."
Salgado, who has lived in the community most of his life, says the butterflies were considered gifts from the spirits, and good luck. But they have vanished, and the water is going too.
"There is going to be a war over the lack of water," Salgado says. "And it is caused by the logging."
Stephen Kiehl traveled to Mexico on a fellowship from the International Reporting Project at the Johns Hopkins University.