Monarch Butterflies in North America Found to be Vulnerable to Extinction

For Immediate Release

March 10, 2015

Sarina Jepsen, Endangered Species Program Director, Xerces Society for Invertebrate Conservation; (971) 244-3727, [email protected]
Bruce Young, Director of Species Science, NatureServe; (703) 908-1805, [email protected]

Monarch Butterflies in North America Found to be Vulnerable to Extinction

Conservation Status and Ecology of the Monarch Butterfly in the United States

PORTLAND, Ore.—A newly completed assessment has found that monarch butterflies in North America are vulnerable to extinction. The assessment was undertaken by NatureServe and the Xerces Society for Invertebrate Conservation, and results were published in a report released by the U.S. Forest Service yesterday.

NatureServe and the Xerces Society used NatureServe’s conservation status assessment methodology to determine the level of imperilment of the monarch. The methodology has been successfully applied to hundreds of species of animals. Using data on population abundance, trends, and threats, the team of scientists determined that while the monarch butterfly species as a whole, Danaus plexippus, is apparently secure, the subspecies occurring in North America, Danaus plexippus plexippus, is vulnerable to extinction. Under the assessment, the North American monarchs were split into an eastern population that migrates from as far north as southern Canada to central Mexico each fall, and a smaller western population, that largely migrates to coastal California to spend the winter. The eastern monarch population was assessed as “critically imperiled” due to recent rapid decline and widespread threats. The western population, with a slightly slower rate of decline and less widespread threats, was categorized as “vulnerable to imperiled.”

“Our findings show that even a widespread and common insect can face dramatic population declines in an alarmingly short period of time,” said Bruce Young, NatureServe’s Director of Species Science. “The time is now to intensify continent-wide efforts to reduce the threats to this iconic species and prevent it from succumbing to the fate that has befallen far too many other species.”

The assessment was done as part of a report prepared for the U.S. Forest Service. The report, Conservation Status and Ecology of the Monarch Butterfly in the United States, summarizes the monarch’s North American distribution, life history, population, current conservation status, and potential causes of decline. In addition, the authors include a set of breeding and overwintering habitat management recommendations. This report aims to inform government agencies charged with biodiversity protection, as well as conservation organizations and the public in general, about the threats to and current conservation status of this much-loved, iconic insect.

“The conclusions of this assessment are consistent with the widespread reports that the monarch population has declined,” said Sarina Jepsen, endangered species director at the Xerces Society. “We now need to restore vast areas of the landscape with milkweed – the monarch butterfly’s essential host plant – and nectar plants if we hope to save this spectacular migration.”



The images below can be used by any media outlet. Please include a photo credit with any use.


Credit: Courtesy hspauldi/Wikimedia Commons

Monarchs Clustering on Redwood Tree at Private Property in Monte

Credit: Carly Voight/The Xerces Society for Invertebrate Conservation


For More Information

Download Conservation Status and Ecology of the Monarch Butterfly in the United States.

Read more about Xerces’ Monarch Conservation Campaign, including efforts to conserve overwintering sites in California and restore breeding habitat in key regions of the United States.

The Xerces Society for Invertebrate Conservation
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