The first monarchs arrive in Mexico's wintering grounds

The first monarch butterflies arrived in their wintering areas in the mountains of central Mexico, almost a week later than usual.

Millions of monarchs annually migrate 3,400 miles (5,500 km) from the United States and Canada.

Butterflies usually arrive in Mexico on November 1, the day of the death holiday.

The Ministry of Environment announced Wednesday that the first butterflies were not seen in the reserve in the west of Mexico before November 6.

The ministry said the butterflies were delayed as they waited for rainy weather around the US-Mexico border.

They spend the winter grouped in fir trees and pines. Last year, monarchs covered about 2.48 hectares (6.12 acres), down about 14.7% from the previous winter. In 1996-97 they covered an area of ​​18 hectares.

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