Monarch butterflies return to Mexico on annual migration
A monarch butterfly takes off from a tree trunk in the winter nesting grounds of El Rosario Sanctuary, near Ocampo, Michoacan state, Mexico, Jan. 31, 2020. The first monarch butterflies have appeared in the mountaintop forests of central Mexico where they spend the winter. Mexico's Environment Department said Saturday, Saturday, Nov. 5, 2022, that the first butterflies have been seen exploring the mountaintop reserves in Mexico State and Michoacan. Credit: AP Photo/Rebecca Blackwell, File

Mexico's Environment Department said Saturday that monarch butterflies have appeared in the mountains of central Mexico.

The first butterflies have been seen exploring the mountaintop reserves in the states of Mexico and Michoacan.

The monarchs did not show up for a few days. They usually arrive for the Day of the Dead in November. The orange and black butterflies were associated with the souls of the dead.

The largest traditional wintering grounds are Sierra Chincua, El Rosario and Cerro Peln.

Depending on the weather, the main group of butterflies is expected to arrive in the coming weeks.

It's too early to say how big this year's migration will be from the US and Canada. The counts are usually done in January when the butterflies have settled into the trees.

The number of butterflies doesn't correlate with the number of acres they cover when they clump together.

More monarch butterflies arrived last year. The butterflies may be able to adapt to more extreme bouts of heat or dry weather by changing their departure date.

monarchs migrate back to the US and Canada in March

The milkweed where the monarchs lay their eggs and the loss of habitat north of the border are all threats to the species' migration. There are illegal logging and loss of tree cover in Mexico.

The monarch butterfly was added to the "red list" of threatened species and categorized as "endangered", two steps away from extinction.

The population of monarch butterflies in North America has fallen between 22% and 72% over the last 10 years according to the group.

The monarch's migration is the longest of its kind.

The butterflies travel thousands of miles after wintering in Mexico. At the end of summer, the offspring return to Mexico.

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