More Monarch butterflies return to Mexico

A monarch butterfly perches on a branch in the Piedra Herrada sanctuary near Valle de Bravo, Mexico, last week. CHRISTIAN PALMA AP

PIEDRA HERRADA, MEXICO

More Monarch butterflies appear to have made the long flight from the U.S. and Canada to their winter nesting ground in western Mexico, raising hopes after their number dropped to a record low last year. But experts still fear that unusual cold temperatures will threaten the orange and black insects.

While an official census won’t be ready until mid-January, observers are seeing healthy populations of butterflies bunched together on fir and pine trees in protected sanctuaries, said Gloria Talavera, director of the official monarch butterfly reserve.

“We’re encouraged, because we’ve seen more,” Talavera said Monday.

But cold forecast for this winter, she said, “could put at risk the whole migratory phenomenon. … We will be saying a prayer each day until mid-February.”

More Monarch butterflies return to Mexico