ROANOKE TIMES
Copyright (c) 1996, Roanoke Times
DATE: Sunday, January 7, 1996 TAG: 9601110042
SECTION: NATIONAL/INTERNATIONAL PAGE: A-3 EDITION: METRO
DATELINE: EL ROSARIO, MEXICO
SOURCE: MOLLY MOORE THE WASHINGTON POST
AS MUCH AS 35 PERCENT of the monarch population in the central highlands was killed by a rare freeze. The deaths have environmentalists up in arms.
High on the snow-capped ridges of the central Mexican highlands, thousands of tiny orange-and-black corpses litter the ground, their lacy wings in tatters and their velvety black bodies crumpled.
Above the melting snows, tens of thousands of surviving monarch butterflies cling to fir branches in mammoth clumps of orange to auburn wings, seeking warmth in a mass of fragile bodies.
The plight of the migrating monarchs - brought on by rare snows in their Mexican winter resting grounds - has sent Mexico into an uproar, stirring widespread hand-wringing and an acrimonious debate among environmentalists from three nations over the extent of the disaster.
``Butterflies are falling from the trees,'' said Homero Aridjis, leader of the Group of 100, a Mexican environmental lobbying organization that first reported the monarch kills and estimates that as much as 35 percent of the winter population - about 20 million butterflies - have died in an unusual cold snap during the past week. ``This is just devastating.''
But the Mexican government, weary of bad economic news, has tried to play down the monarch kill as one of its most popular natural tourist attractions enters the high season.
Government agencies, and some private groups that have sent investigators trekking into the butterfly sanctuaries 11,000 feet up the rugged mountains 100 miles west of Mexico City, place the snow-related death toll at somewhere between 10 percent and 15 percent of the monarch population.
The fragile creature is a ubiquitous symbol of summer in gardens across the United States - and an important barometer of environmental degradation across three countries.
In recent years monarch populations have been diminished by agricultural pesticides that poison the flowers on which they feed, deforestation of their mating grounds, pollution and urbanization.
Even without the manmade problems, the life of a monarch has never been easy. Some years, in some sanctuaries, birds gobble up to 40 percent of the butterflies, according to Juergen Hoth, a butterfly expert for the World Wildlife Fund.
``And that's only birds,'' said Hoth. ``Then you have to add mice. Then you have to add winter...and exhaustion and the depletion of food.''
But, Hoth said the unusual snow kills this year are worrisome.
``Butterflies seem to cope with large reductions in population,'' he said. ``We don't know how large, however.''
Long before the advent of continental free trade, the monarch butterfly has been freely making the 3,100-mile trip from Canada, through the United States to the mountains of central Mexico, requiring up to five generations of butterflies to complete the round trip.
New generations of butterflies often return to the same tree as their parents and grandparents, according to scientists. But in recent years, population growth, logging and agriculture have eaten away at the wintering grounds of the monarchs in central Mexico and the southern United States. Under pressure from environmental groups, the Mexican government a decade ago designated five monarch sanctuaries in the high elevations of the fir forests in the state of Michoacan.
Even so, illegal logging continues in the forests, and villagers have planted corn and other crops in the buffer zones surrounding the sanctuaries, depleting the tree cover that serves as umbrella-like protection for the butterflies.
``It is like punching holes in their blankets,'' said Aridjis, the Group of 100 leader, who grew up in a village near the monarchs' wintering grounds where he developed a special affinity for the butterflies.
The melting snows from this past week's storm - which occur only about twice a decade in this region of Mexico - have left rivers of mutilated monarch wings, bodies and broken antennae on the forest floor. Injured butterflies make futile attempts at flying with their crushed wings.
But, environmentalists and government scientists don't even agree on how many butterflies populate the sanctuaries. Some environmentalists put the number at 60 million, while government agencies estimate 124 million.
Regardless of the numbers, the monarch population had only just begun to recuperate from an unusually cold Mexican winter in 1992 when millions of the insects froze to death. Scientists fear that the combination of the two deadly winters could devastate the monarch population.
The survivors - and there are tens of millions of them - still cover dozens of huge fir trees in the high mountain forest of the largest sanctuary, coating the trees with a shell of orange wings in a spectacular, but somewhat-subdued version of the display that draws thousands of tourists up these mountainsides in the winter months.
In the cold weather, the butterflies move little, preferring to clump together in giant nests of bodies so heavy that the branches of the fir trees droop under their weight. As the weather warms in late January, great swarms of millions of butterflies will begin floating through the forests in search of places to lay their eggs.
When the eggs hatch and the larvae mature into butterflies, the youngsters will begin the migration north through the United States and into Canada, stopping along the way to lay new eggs and start new generations to continue the northward journey.
But many environmentalists now fear that with the deaths of millions of monarchs here, far fewer butterflies will be populating U.S. and Canadian gardens this summer.
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