The population wintering in central Mexico's forests occupied 4.42 acres, up from 2.22 acres during the previous winter.

A study, published Thursday in the journal Science, found that 22% of butterflies in the United States disappeared between ...

The monarch butterfly population has rebounded from a near record low number in 2024, according to the latest annual survey ...

Butterfly populations across the United States are declining, a trend reflected in the Western monarch butterfly population ...

Monarchs from east of the Rocky Mountains in the United States and Canada overwinter in the mountains west of Mexico City.

MEXICO CITY (AP) — The number of monarch butterflies wintering in the mountains ... compared to only 2.2 acres (0.9 hectares) the year before. Last year’s figure represented a 59% drop from ...

The number of monarch butterflies wintering in the mountains ... The highest number recorded was 1.2 million in 1997. The organization announced in February that it counted just 9,119 monarchs ...