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Monarch Butterfly ESA Listing Decision Deadline Extended

May 24, 2019


  • Population Trends

The U.S. Fish and Wildlife Service has been working to assess the monarch’s status in response to a petition to list the species under the Endangered Species Act. In an agreement approved by the court, the deadline to determine whether the species warrants federal protection has been extended to December 15, 2020.

The deadline extension was agreed to by the Center for Food Safety and Center for Biological Diversity, who had petitioned the Service to formally assess the status of the butterfly. The extension allows the Service to focus additional effort on obtaining the best available science, including data from the latest overwintering surveys.

“Conservation of the monarch and other at-risk species is a Service priority,” said Charlie Wooley, the Service’s acting Midwest Regional Director. “Properly assessing the status of the monarch butterfly is a vast and complex undertaking. It involves significant data collection and analysis across a huge swath of North America. We thank the petitioners for agreeing to the additional time to ensure we get this right.”

Recent and rapid growth in partnerships and conservation efforts across sectors have made great strides towards conserving monarchs and their habitats. With this extension of the proposed listing decision, we have an opportunity to ramp up our collective efforts.

It is critical to implement plans such as the Mid America Monarch Conservation Strategy, the Western Monarch Conservation Plan, the Rights of Way as Habitat CCAA, and the identified priorities in the Monarch Conservation Implementation Plan. Individuals can make an important difference for monarchs in their communities as well - find out how.

Eastern monarchs need an additional 1.3-1.8 billion stems of milkweed and abundant nectar sources to sustain a viable overwintering population size. Preliminary western habitat targets are 50,000 acres of habitat restored in the Central Valley, and an immediate Western Monarch Call to Action.

All hands on deck are needed to meet these ambitious goals. We must continue this critical work, and continue to track our efforts to inform the ongoing listing decision. MJV will strengthen our efforts to provide and monitor habitat through our Integrated Monarch Monitoring Program, and the USFWS will continue to receive and evaluate monarch conservation projects through the Monarch Conservation Database.  

The eastern monarch population estimate rose last winter to over 6 hectares of occupied overwintering forest. However, the western monarch population plummeted to an all-time low- less than 30,000 individual butterflies were recorded – a decline of more than 99% from estimates in the 1980s.

With at least one more year of overwintering data, and an opportunity to enact and expand committed monarch conservation strategies, the USFWS will issue an informed decision regarding whether or not the monarch butterfly is warranted for Endangered Species Act listing in December 2020.

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The Monarch Joint Venture is a national partnership of federal and state agencies, non-governmental organizations, businesses and academic programs working together to conserve the monarch butterfly migration. The content in this article does not necessarily reflect the positions of all Monarch Joint Venture partners. Header photo by Wendy Caldwell.