'Landmark Victory': US Proposes Endangered Species Protections for Monarch Butterfly

Biodiversity defenders on Tuesday welcomed a "long overdue" move by the U.S. Fish and Wildlife Service toward protecting the monarch butterfly under the Endangered Species Act—the result, the Center for Biological Diversity said, of a lawsuit filed by several groups to safeguard the pollinators and their fragile habitat.

The FWS proposed designating the butterfly as threatened with extinction, four years after monarchs were placed on a waiting list for protection.

"For too long, the monarch butterfly has been waiting in line, hoping for new protections while its population has plummeted. This announcement by the Fish and Wildlife Service gets this iconic flier closer to the protections it needs, and given its staggering drop in numbers, that can't happen soon enough," said Steve Blackledge, senior director of conservation campaigns for Environment America.

Monarch butterflies journey from Mexico each spring to points across the United States east of the Rocky Mountains to pollinate and reproduce. When cooler weather arrives they migrate back to the south for the winter.

But their populations have declined by more than 95% from over 4.5 million in the 1980s, leaving the western monarch with a 99% chance of becoming extinct over the next six decades, according to federal scientists.

The decline has been driven by the widespread use of herbicides like Roundup on milkweed, the monarch's sole food source, as well as the use of neonicotinoid insecticides. Millions of monarchs are also killed by vehicles annually during their migration, and in their winter habitats they face the loss of forests due to logging.

"The monarch butterfly is an iconic North American species and like other such iconic species, including the bald eagle and American peregrine falcon, it too deserves a chance at recovery."

Rising temperatures have also disrupted the monarch's reproduction and migration, with warmer weather tricking them into staying in the north later in the year.

"The species has been declining for a number of years," FWS biologist Kristen Lundh toldThe Washington Post. "We're hoping that this is a call to everybody to say this species is in decline, and now is our opportunity to help reverse that decline."

Western monarchs are down to an estimated 233,394 butterflies, while experts say there are several million eastern monarchs in existence.

"The protections that come with Endangered Species Act listing increase the chance that these precious pollinators will rebound and recover throughout their historic range," said Andrew Carter, director of conservation policy for Defenders of Wildlife. "The monarch butterfly is an iconic North American species and like other such iconic species, including the bald eagle and American peregrine falcon, it too deserves a chance at recovery."

The FWS is also proposing to designate 4,395 acres of the western monarch's overwintering sites as a critical habitat.

If the butterfly's protections are finalized—a process that could be completed by the end of 2025—landowners would be required to get federal approval for development that could harm the monarch.

During his first term, President-elect Donald Trump weakened the Endangered Species Act, limiting the definition of a "critical habitat."

"Today's monarch listing decision is a landmark victory 10 years in the making. It is also a damning precedent, revealing the driving role of pesticides and industrial agriculture in the ongoing extinction crisis," said George Kimbrell, legal director at the Center for Food Safety. "But the job isn't done... The service must do what science and the law require and promptly finalize protection for monarchs."