Good news for biodiversity: the presence of the monarch butterfly in Mexican overwintering forests increased by 64% during the 2025–2026 season. This was reported by environmental authorities such as Semarnat and Conanp, in collaboration with WWF Mexico.
This increase translates to an occupation of 2.93 hectares of forest, compared to the 1.79 hectares recorded the previous year. A key figure confirming that the recovery trend for this species continues for the second consecutive year.
The monarch butterfly undertakes one of the most impressive migrations on the planet: it travels up to 4,000 kilometers from Canada and the United States to the forests of Michoacán and the State of Mexico, where it spends the winter.
Why has the monarch population increased?
The increase is mainly due to better weather conditions during their breeding season in the United States. There was more rainfall in the spring and summer, which favored the growth of plants and, consequently, a greater number of eggs and larvae.
Additionally, during their journey to Mexico, there was less drought, which allowed them to find more nectar-bearing flowers along the way. This was key to enabling more butterflies to complete their migration.
During this season, nine colonies were recorded: five within the Monarch Butterfly Biosphere Reserve and four outside it. The largest was located in the El Rosario ejido, in Michoacán.
Although the data is encouraging, experts warn that significant risks remain, such as climate change, pesticide use, and the impact of tourism. For this reason, a new Action Plan for their conservation was announced.
In addition to its beauty, the monarch butterfly plays a vital role as a pollinator, and its habitat even benefits our beautiful Mexico City, as these forests help capture water for the Cutzamala System.
