U.S. wildlife officials plan to list monarch butterflies as threatened species

MADISON, Wis. — U.S. wildlife officials announced a decision Tuesday to extend federal protections to monarch butterflies, following years of warnings from environmentalists that populations are shrinking and the beloved pollinator may not survive climate change.

The U.S. Fish and Wildlife Service plans to add the butterfly to the endangered species list late next year, after an extensive public comment period.

“The iconic monarch butterfly is cherished throughout North America and fascinates children and adults throughout its fascinating life cycle,” said Martha Williams, director of the U.S. Fish and Wildlife Service, in a news release. “Despite its fragility, it is remarkably resilient, like many things in nature if we give them a chance. The science shows that the monarch needs that opportunity, and this proposed listing invites and builds on unprecedented public participation in shaping monarch conservation efforts.”

The Endangered Species Act provides comprehensive protection for species listed by the Wildlife Service as threatened or endangered. By law, it is illegal to import, export, possess, transport or kill an endangered species. An endangered listing allows exceptions to this protection.

In the case of the monarch, the proposed listing would generally prohibit anyone from killing or transporting the butterfly. People and farmers could continue to remove milkweed, an important food source for monarch caterpillars, from their gardens, backyards and fields, but they would be prohibited from making changes to the land that would make it permanently unusable for the species. Occasional killings due to vehicle attacks would be allowed, people could continue to transport fewer than 250 monarchs and use them for educational purposes.

“We want people to continue raising caterpillars and monarchs in their homes and using them for education,” said Lori Nordstrom, assistant regional director for ecological services for the wildlife service’s Midwest region.

The proposal would also designate 4,395 acres (1,779 hectares) in seven coastal California counties where monarchs west of the Rocky Mountains migrate in winter as critical habitat for the butterfly. The designation would prohibit federal agencies from destroying or altering that habitat. The designation does not prohibit all development, but landowners who require a federal license or permit for a project should work with the conservation service to limit damage.

It’s been a long road to get a formal proposal from the wildlife agency.

The Center for Biological Diversity petitioned the agency in 2014 to list the monarch as endangered. The agency launched an investigation into the butterfly’s status in late 2014 and concluded six years later that listing was warranted but that other species were prioritized. The center filed a federal lawsuit and won a settlement in 2022 that called for the government to decide by September 2024 whether to list monarchs. The government provided an extension until December.

Monarchs are found throughout North America. They are known for their striking orange-black wings and are symbolic of sunny summer days. But conservationists have been concerned over the past decade that monarch numbers are declining.

Monarchs in the eastern United States spend winters in Mexico. Monarchs west of the Rocky Mountains typically migrate to coastal California, where their colorful clusters in orchards attract nature lovers and tourists.

World Wildlife Fund Mexico, a division of the independent global conservation organization, follows the monarch migration in that country. The group released data in February showing the species occupied just 2.2 acres of their traditional wintering groves in 2023-2024. That’s a 59% decrease in area from the previous year, when the organization observed monarchs on 2.2 hectares.

The Xerces Society for Invertebrate Conservation collects data from wintering locations along the California coast, northern Baja California and some inland locations in California and Arizona. The number of monarchs volunteers counted in November – the peak of the migration season when most butterflies are present – ​​has fallen by a whopping 81% over the past quarter century, from 1,235,490 monarchs at 101 sites to just 233,394 at 257 sites last year .

Environmentalists say monarch populations are shrinking due to warmer temperatures brought on by climate change, agricultural expansion and herbicides that have stunted the growth of milkweed — the main food source for monarch caterpillars.

The Convention on the Conservation of Migratory Species of Wild Animals (CMS), which is committed to the conservation of migratory animals worldwide through treaties and regional agreements, has warned that as the planet warms, milkweed could shift poleward to find more favorable growing conditions. That could force monarchs to migrate longer distances, reducing the time spent breeding.

Temperature changes due to climate change can also wreak havoc on monarch migration. According to the convention, warmer temperatures could delay or prevent the monarchs’ return north.

Monarchs also need to hibernate in forests where the temperature is cold enough to slow their metabolism, but not so cold that they freeze. That’s why the CMS has warned that temperature shifts could spell doom for the insects.

Kristen Lundh, a biologist with the wildlife agency, said the agency chose to list monarchs as threatened rather than endangered because they are not in immediate danger of extinction throughout all or a significant portion of their range. Monarchs west of the Rockies have a 95% chance of becoming extinct by 2080, she said, but most of the U.S. monarch population — 90% — is east of the Rockies and that population has a 57% chance up to 74% of extinction. by then, she said.

Tuesday’s announcement begins a 90-day public comment period. The wildlife agency will then decide whether to adjust the proposal, publish the list or discontinue the effort. The agency has until December 2025 to publish the list if progress is made.

___

Follow Todd Richmond on X, formerly Twitter: @trichmond1