Decline in number of monarch butterflies wintering in Mexico

By MARK STEVENSON
Associated Press

MEXICO CITY (AP) — The number of monarch butterflies wintering in the mountains of central Mexico dropped by 22%, and the number of trees lost in their favored wintering ground more than tripled compared to last year. Humberto Peña, the director of Mexico’s nature reserves, says frosts and “extreme temperatures” in the United States may have played a role in the butterfly’s decline. The area occupied by the monarchs in the mountains west of Mexico City dropped to 5.4 acres (2.21 hectares) from 7 acres (2.84 hectares) last year. Each year the monarchs return to the United States and Canada on an annual migration.