Conservationists demand feds list monarch butterfly as threatened

SAN FRANCISCO (CN) — Two nonprofits sued the Trump administration Thursday to put pressure on officials regarding federal protections for monarch butterflies, a species that has seen rapid decline in population numbers in the last few decades.

The Center for Biological Diversity and the Center for Food Safety seek official protections through a finalized listing and comprehensive protection plan for the well-known insect, under the U.S. Endangered Species Act. The orange and black butterfly was first proposed for protection by the U.S. Fish and Wildlife Service in December 2024 as a threatened species, with its final listing due in December 2025.

The environmentalists say Fish and Wildlife has stalled its final listing rule, which may increase the species’ extinction risk. Threats from pesticides, habitat degradation, development and climate change continue to affect the butterflies.

“In lieu of finalizing the rule, the Trump administration moved publishing the monarch rule to ’long-term actions’ and did not set a date for issuance,” Tierra Curry, endangered species co-director at the Center for Biological Diversity, said in an email. “This administration has not listed a single species under the ESA, and has instead recategorized hundreds of needed actions as ’long-term’ with no deadline.”

The lawsuit, filed in the U.S. Northern District of California, names the U.S. Fish and Wildlife Service, its director Brain Nesvik, and U.S. Department of the Interior Secretary Doug Burgum as defendants.

“Plaintiffs’ members’ interests in protecting and recovering the butterfly and its habitat are directly harmed by the service’s failure to issue a timely final rule, delaying critical protections under the Endangered Species Act that can put the monarch butterfly on a path to recovery,” the organizations say in their complaint.

They say the monarch has lost over 165 million acres of breeding habitat, mostly grasslands, to agriculture and the industry’s need to use herbicide. Monarch caterpillars eat only one plant, milkweed, which is often sprayed with toxic neonicotinoid insecticides.

Monarch butterflies pollinate a variety of flowers and plants, and are a crucial components of their ecosystem.

“All stages of the monarch life cycle are important in the food web with hundreds of different animals consuming monarch eggs, caterpillars, and adults, despite the toxicity they acquire from milkweed,” said Curry. “In their wintering groves in Mexico, they are an important food source for migratory songbirds.”

In 2014, the environmental nonprofits and the Xerces Society for Invertebrate Conservation petitioned for the monarch to be added for protection under the Endangered Species Act. The species was put on the candidate waiting list in 2020. To get an official date for listing, the groups sued the service.

Monarch butterflies undertake vast migrations, some up to 3,000 miles, from eastern North America to their overwintering lands in Mexico. The butterflies that make the journey are known as a “super generation,” delaying reproduction and living up to nine months to fly the distance. Those that do not make the epic crossing live approximately four to six weeks.

“Comprehensive protections are urgently needed to ensure a future for these migratory wonders,” Curry said. “Monarchs unite us and it’s disgraceful that their future is being sacrificed to political nonsense.”

The Interior Department declined to comment on pending litigation and Fish and Wildlife did not immediately respond to a request for comment.