Mar 25, 2002 — The monarch butterflies that spend the summer here in the North Country winter over in the mountains of central Mexico. Their annual migration is one of the world’s natural wonders. But this winter, an ice storm blasted Mexico's butterfly sanctuary. Tens of millions of monarchs died. Scientists say logging and subsistence farming have damaged the sanctuary's tree canopy, leaving the butterflies vulnerable. Now, the World Wildlife Fund and the Mexican government are spending millions of dollars, hoping to convince locals that the forest should be saved. North Country Public Radio's Brian Mann visited the mountain region. He found that many researchers see this effort as the monarchs' last chance.