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 on March 9.

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.”

Read More | The Xerces Society | NatureServe

Previous Coverage: Monarch Butterfly Moves Toward Endangered Species Act Protection