Pacchiano and Jewell at the butterfly reserve this week Pacchiano and Jewell at the butterfly reserve this week. milenio/nelly salas

Big increase forecast in monarch butterflies

At least three times as many are forecast to make the annual migration

It’s monarch butterfly season in the forests of Michoacán and the State of México, where experts are anticipating a massive increase — at least three times as many as last year — in the number of butterflies that make the annual migration from the U.S. and Canada.


The importance of the migration to U.S. authorities was enunciated Thursday during a visit by U.S. Interior Secretary Sally Jewell.

“Mexico, the U.S. and Canada have many species that don’t know our political borders, that cross the borders freely,” she said during a conference at the Piedra Herrada research reserve, adding that the United States is working on replanting milkweed on three million hectares of land and designating pesticide-free areas.

Jewell also asked for the cooperation and help of Mexico and Canada, “because we can’t protect the monarchs by ourselves; their habitat must be protected to ensure their survival.”

The goal, she said, is “225 million monarch butterflies returning right here to Mexico every year. We believe we can get there by working together and it sounds like we may be on our way, we hope.”

That goal means that the butterflies will have to cover an area of six hectares by 2020. This compares to a record high of nearly 19 hectares during the 1996-1997 winter season, a figure that has been in decline since.

The decline has been blamed on illegal logging in the butterflies’ Mexican wintering grounds and the drop in milkweed on which they feed due to the use of pesticides in the United States.


Mexican authorities have launched operations to combat the logging, announcing arrests of loggers in recent months, but the World Wildlife Fund (WWF) reported in August a drastic increase in clandestine tree cutting in some reserves.

Jewell’s visit was to the part of the Monarch Butterfly Biosphere Reserve that lies in the State of México, where she was accompanied by Environment Secretary Rafael Pacchiano, just as the first specimens started arriving. Both politicians agreed that this season will see triple the number of monarchs wintering in their Mexican reserve.

Last year they covered more than 1.13 hectares, an improvement over the sharp decrease recorded during the 2012-2013 season, where the monarchs’ coverage barely surpassed half a hectare.

“We are very glad to report that calculations done before the landfall of Hurricane Patricia showed the monarch presence could cover up to four hectares, a clear indication that the efforts mentioned by Secretary Jewell are having a positive effect,” said Pacchiano.

On that note, the head of the nation’s protected areas commission said that few butterflies succumbed during the category 5 hurricane, although it — along with a cold front — delayed their arrival by a few days.

“The reserve is also ready to receive visitors in six different shelters, and officially the season will start on November 21,” added Alejandro del Mazo.

The arrival of monarch butterflies means jobs for 250 families at the Piedra Herrada sanctuary alone.

The Monarch Butterfly Biosphere Reserve is a world heritage site containing most of the over-wintering sites of the eastern population of the monarch butterfly. The reserve and its 56,000 protected hectares was established in 1980.

Source: Milenio (sp), Discovery (en)

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  • Güerito

    The hyperlink to the August WWF report is not working. Here’s an AP article on that report:

    • Thank you for the heads up and that link, Güerito.

      We have edited the hyperlink and it now correctly leads to a story we published in August.

  • PintorEnMexico

    Happy to hear some good news!

  • Ward Johnson

    Two years ago, my wife, and and I started a foundation to help to save the monarchs.

    It is called SaveOurMonarchs Foundation and is devoted to helping to save the monarchs by distributing FREE Milkweed Seed Packets to anyone requesting them. You can get Swamp Milkweed seeds at

    No Milkweed, No Monarchs!

    Ward Johnson

  • Jared Buker

    Wonderful news! I worked hard this past summer in my small town of Lincoln, VT to make sure people knew when to and when NOT to mow their milkweed, and am proud to have raised about 15 that were all released.

  • Kathleen Crouse-Bradley

    Plant milkweed, no pesticides, you can even help protect a chrysalis 🙂