MADISON, Wis. (AP) — U.S. wildlife officials announced a decision Tuesday to expand federal protections for monarch butterflies after years of warnings from environmentalists that populations are declining 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 by the end of next year, after a lengthy public comment period.

“The iconic monarch butterfly is cherished throughout North America, captivating children and adults throughout its fascinating life cycle,” said Martha Williams, director of the U.S. Fish and Wildlife Service, in a press release . “Despite its fragility, it is remarkably resilient, like many things in nature when you just give them a chance.”

The Endangered Species Act provides broad protections to species that the Wildlife Service considers endangered or threatened. Under the law, it is illegal to import, export, possess, transport or kill an endangered species. An endangered listing allows for exceptions to these protections.

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, a key 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 them permanently unusable for the species. Accidental killings resulting from vehicle collisions would be allowed, people could continue to carry fewer than 250 monarchs and still use them for educational purposes.

“We want people to continue to raise caterpillars and monarchs in their homes and use them for educational purposes,” said Lori Nordstrom, deputy regional director of 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 for the winter as critical habitat for the butterfly. The designation would prohibit federal agencies from destroying or modifying this habitat. The designation does not prohibit all development, but landowners who need a federal license or permit for a project should work with the wildlife department to mitigate damages.

It was a long road to obtain a formal proposal from the wildlife service.

The Center for Biological Diversity and other conservation groups asked the agency in 2014 to list the monarch as threatened. The agency launched a review of the butterfly’s status in late 2014, concluding six years later that listing was warranted but that other species took priority. The center filed a federal lawsuit and won a settlement in 2022 calling on the government to decide whether to list monarchs by September 2024. The government was granted an extension until December.

“The fact that a butterfly as widespread and beloved as the monarch now faces an extinction crisis is a distress signal that warns us to take better care of the environment we all share,” said Tierra Curry, senior scientist. in the center.

Monarchs are found throughout North America. Known for their distinctive orange and black wings, they are the symbol of sunny summer days. But conservationists have been concerned about declining monarch numbers for a decade.

Monarchs from the eastern United States spend the winter in Mexico. Monarchs west of the Rocky Mountains typically migrate to coastal California, where their colorful flocks in groves of trees attract nature lovers and tourists.

World Wildlife Fund Mexico, a branch of the independent global wildlife conservation organization, follows the migration of monarchs in this country. The group released data in February that showed the species occupied only 2.2 acres (0.9 hectares) of its traditional wintering groves in 2023-2024. This represents a 59% decrease in area from the previous year, when the organization observed monarchs on 5.5 acres (2.2 hectares).

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

Environmentalists say monarch populations are declining because of warmer temperatures brought on by climate change, agricultural expansion and herbicides that have hampered the growth of milkweed, the monarch caterpillars’ main food source.

The Convention on the Conservation of Migratory Species of Wild Animals (CMS), which works globally to conserve migratory animals through regional treaties and agreements, warned that as the planet warms, milkweed could move toward the poles to find more favorable growing conditions. This could force monarchs to migrate longer distances, reducing the time spent breeding.

Temperature changes caused by climate change could also disrupt monarch migration. Warmer temperatures could delay or prevent the monarchs’ return north, according to the convention.

Monarchs must also overwinter in forests where temperatures are cold enough to slow their metabolism, but not so cold that they freeze. The CMS therefore warned that temperature changes could spell doom for insects.

Kristen Lundh, a wildlife service biologist, said the agency chose to propose listing the monarchs as threatened rather than endangered because they are not in immediate danger of becoming extinct all or any of them. significant part of their range. Monarchs west of the Rockies have a 95% chance of going extinct by 2080, she said, but most of the U.S. monarch population — 90% — is in the east of the Rocky Mountains and this population faces a 57% to 74% probability of extinction. at that time, she said.

Tuesday’s announcement kicks off a 90-day public comment period. Then the wildlife agency will decide whether to modify the proposal, publish the list or abandon the effort. The agency has until December 2025 to release the announcement if it moves forward.

The proposal raises questions for groups that advocate for voluntary conservation in hopes of avoiding federal listing — and the potential restrictions that could come with it.

Matt Mulica is the lead convener of Farmers for Monarchs, a group of farmers, ranchers and agricultural businesses that includes the American Farm Bureau Federation and the American Soybean Association.

Mulica said farmers have worked alone for years to maintain the monarch’s habitat. It’s too early to know what a threatened agricultural listing would mean for agriculture, he said.