Monarch Butterfly Population in Mexico Doubles After Record Lows

The Monarch butterfly population in Mexico has doubled this winter compared to last season, marking a major rebound after a troubling 2024. The Ejido El Rosario sanctuary in Michoacan recorded the highest concentration, with colonies covering 1.79 hectares, up from 0.90 hectares last year.

Perched at 3,000 meters above sea level, El Rosario is the largest Monarch hibernation forest in the world, hosting half of all Monarchs migrating to Mexico. Conservation efforts, including forest protection and fire prevention, have played a key role in this increase.

Despite the rise, climate change and pesticides remain serious threats. Since 2022, Monarch butterflies have been classified as endangered, with habitat destruction endangering their migration from Canada and the U.S. to Mexico’s 56,000-hectare Monarch Butterfly Biosphere Reserve.

While this year’s population surge is promising, experts warn more action is needed to ensure the survival of one of nature’s most extraordinary migrations.