The number of monarch butterflies wintering in Mexican forests declined for a second consecutive year, a government official said Monday.
Alejandro Del Mazo, Mexico’s commissioner for protected areas, said the monarchs clumped in trees covering about 6.12 acres (2.48 hectares) this winter. That was down about 14.7 percent from the 7.19 acres (2.91 hectares) the previous winter.
The monarch butterflies’ migration is measured by the area they cover in pine and fir forests west of Mexico City. Millions of the butterflies make the 3,400-mile (5,500-kilometer) migration from the United States . . .
