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Monarch butterfly annual migration

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2026-10-16 08:15 UTC → 2026-10-17 23:22 UTC · added ~~removed~~

Monarch butterflies are undergoing their annual migration from southern Canada and the northern United States toward central Mexico, a journey exceeding 2,000 miles toward mountain forests for the winter. The migration typically sees its largest wave through September and October. In Texas, the migration has reached areas such as San Angelo. San Angelo State Park hosted a free monarch migration event on October 10, which included a presentation and a guided hike to a monarch waystation at the Bell’s Trailhead to observe the seasonal movement. As the migration progresses into October and November, butterflies arrive in Mexico, coinciding with Day of the Dead celebrations. In Mexican indigenous cultures, such as the Purépecha, Mexica, and Zapotec, the butterflies hold sacred significance and are often viewed as “the souls of the deceased or messengers of the gods,” arriving to visit the living in early November. ~~While~~ Some communities continue to honor them with offerings of flowers and copal. Recent sightings indicate thousands of butterflies have ~~been sighted entering Mexico via~~ begun arriving in northern Mexico. In the state of Coahuila, ~~travelers~~ significant numbers have been reported in municipalities including Sabinas, Ciudad Acuña, Piedras Negras, and Nava, with similar sightings noted in Nuevo León. Cold front number two and northern winds have reportedly acted as environmental catalysts, providing aerodynamic assistance to accelerate the southward journey. Monitoring efforts by the Profauna Association’s ‘Correo Real’ program and the ‘Project Monarch’ mobile application are documenting specimens. Researchers continue to utilize BlūMorpho ultra-lightweight solar transmitters weighing approximately 60 milligrams to track migration routes. Travelers heading to the oyamel forests of the Monarch Butterfly Biosphere Reserve in Michoacán and Estado de México are advised to confirm specific opening dates and schedules for sanctuaries like El Rosario, Sierra Chincua, El Capulín, or Macheros, as seasonal arrival does not always guarantee immediate access. Environmental guidelines recommend using specialized guides and strictly adhering to the prohibition against removing any butterflies. To track these movements, researchers are utilizing BlūMorpho, ultra-lightweight solar transmitters weighing only 60 milligrams. The official 2025–2026 season for the Monarch Butterfly Biosphere Reserve is scheduled from November 22, 2025, to March 31, 2026. Macheros.

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