Beloved Minnesota visitors, monarch butterflies could join the list of threatened species

Thousands of monarch butterflies are making their annual arrival in Minnesota — one of the final destinations on the insects’ migration from Mexico.

Fewer of the beloved butterflies are showing up in the Midwest compared to two decades ago. But the region has seen less of a drop compared with an 80% decrease nationally, a phenomenon blamed on habitat loss, widespread pesticide use and climate change.

That decline prompted the U.S. Fish and Wildlife Service under President Joe Biden last year to recommend listing the butterfly as “threatened” under the Endangered Species Act. Whether that listing moves forward remains uncertain, now that President Donald Trump’s administration has proposed changes to the act and cut the agency’s workforce.

Those passionate about monarchs aren’t counting on federal support to save the insects. They say Minnesotans can help monarchs in two vital ways: planting milkweed and reducing pesticide use.

“Monarchs are probably the most charismatic insect, and people love them, and people know them,” said Emilie Snell-Rood, professor of ecology, evolution and behavior at the University of Minnesota. “And so they are very important flagship species for insect conservation.”

At the end of the summer, emerging monarchs from Minnesota fly to Mexico and overwinter there. In spring, it takes one to two generations of monarchs to migrate to Minnesota, where additional generations are born.

The breeding population in the Midwest is faring better than the overwintering population in Mexico. No one knows the exact reasons, but certain gardening practices and climate events in the southern U.S. may be factors in the overwintering population’s predicament, Snell-Rood said. For example, some gardeners plant tropical milkweed which stays green into the winter, triggering monarchs migrating south to stop moving and start reproducing. This also tends to increase disease spread in those butterflies.

After their spring migration, monarchs are likely revamping their numbers when they reproduce in the northern states, she explained. This is why summers in Minnesota are key to the resilience of the entire Eastern monarch population.

In the Midwest, one of the main drivers of that regional decline is the widespread disappearance of milkweed. Monarch caterpillars exclusively feed on the plant’s leaves — and female monarchs only lay eggs on milkweed, said Vera Krischik, associate professor in entomology at the University of Minnesota.

Starting in the early 2000s, the planting of herbicide-resistant crops led to a surge in chemical use that wiped out milkweed from large swaths of farmland, said Tierra Curry, endangered species codirector at the Center for Biological Diversity, a nonprofit advocacy group.

Snell-Rood and Krischik believe that listing the monarch as a threatened species is crucial for the species’ recovery. Federal agencies would create a national recovery plan and funding for monarch conservation that would provide farmers, land managers, and homeowners with the tools and information to support monarchs, Krischik said.

Moreover, the monarch’s listing would prohibit the butterfly’s “take,” meaning anything that harms the species’ survival, such as habitat destruction. Listing the monarch would prompt the agency to designate critical habitat in seven California counties essential for the monarch’s conservation and mandate that federal agencies consult with the Fish and Wildlife Service before undertaking activities that might harm the monarch and its habitat.

Curry expects that the monarch listing will eventually go through. But policy changes and federal layoffs could weaken its effectiveness, she said.

Since a Supreme Court ruling in 1995, “significant habitat modification or degradation that actually kills or injures wildlife” has been widely interpreted to be harmful to listed species. This April, the Trump administration proposed rescinding the definition of “harm” to include only instances of direct harm.

The change would gut protections for native grasslands, clearing the way for farmland conversion that could destroy key milkweed habitat — even with a finalized listing for monarchs. “You can’t protect a species without protecting its home,” Curry said, “Wild animals have to have places to live, and most species are endangered because of harm to their habitat.”

Trump’s staffing and funding cuts also raise concerns about agencies’ ability to maintain endangered species protections.

This year, the unit of the Fish and Wildlife Service that administers the Endangered Species Act is projected to lose 10% of its staff compared to last year. While it is very likely that the proposed listing of monarchs will eventually be finalized, Curry said, given the cuts to scientific staff, she is not confident that the agency would do so by the December 2025 deadline.

In a statement Tuesday, a Fish and Wildlife Service spokesperson said that it’s “implementing necessary reforms to ensure fiscal responsibility, operational efficiency, and government accountability” and that the agency “remains committed to upholding our mission under the Endangered Species Act...”

Scientists say individuals can play a role in saving monarchs from extinction. In 2024, a study based in Chicago found that even small-scale individual efforts to plant milkweed in residential areas could create effective urban breeding habitats for monarchs.

Planting a diversity of milkweed and nectar plants is essential to the survival of monarchs, because it gives them the fuel they need during their long fall migration to Mexico, Krischik said.

Local environmentalists have been encouraging people to create monarch habitats in their backyards for years, creating an expansive network of residential pollinator-friendly spaces.

Save Our Monarchs, a nonprofit that distributes milkweed seeds and raises public awareness on monarch conservation, has launched over 40,000 school gardens and sends out 100,000 seed packets monthly. They offer not only common milkweed seeds, but other nectar plants, like the partridge pea which blooms until October.