Press Release: Monarch butterflies didn’t get the endangered listing they deserve. That might not be a bad thing.

December 17, 2020 Science

This morning, the US Fish & Wildlife Service issued a press release announcing that while Monarch butterflies meet the criteria for being listed as an endangered species, they’re being left off the list for the time being, due to a lack of resources. On the surface, that sounds… bad, right? Or at least confusing. Field Museum scientists who specialize in Monarch conservation are here to break it down and explain why it could actually help the butterflies in the long run.

“It can be hard to think of Monarchs as threatened or endangered, since they’re some of the more recognizable butterflies in the country, and it’s not hard to find them,” says Erika Hasle, a Field Museum conservation scientist whose work focuses on Monarchs. “But they’ve been in a slow decline for the last twenty years. There used to be so many that they’d darken the sky when they migrated, like passenger pigeons, but now there’s only a small fraction left.”

Monarchs are in trouble due to habitat destruction, pesticide use, and climate change. And the aspects of their lifestyle that put them at risk also make saving them a complicated task. “Monarch butterflies are really hard to protect—they migrate across the continent, their caterpillars can only eat milkweed, which is often considered a weed, and their habitat area potentially includes every acre in the country that has greenery on it. If they were to be listed as endangered, it would radically change the way that people use land, and our laws and infrastructure might not be ready to handle it,” says Field Museum ecologist Doug Stotz.

He notes that prematurely listing Monarchs as endangered could wind up turning politicians and their constituents against the Endangered Species Act, which is critical for conservation scientists: “I was concerned about the possibility of Monarchs getting listed because that could be the end of the Endangered Species Act.”

For the time being, Monarchs are in a state of limbo, not listed as threatened or endangered, but still in the running for future years, which Hasle notes is a good thing—that means that scientists won’t need to start over and re-apply for the butterflies to be considered for protection. “Listing a species as endangered is a commitment of resources from the government, and this gives us a wake-up call to work for the legislature and infrastructure we’d need to make that commitment of resources possible,” they add. “This middle ground decision doesn't give us any reason to slow our conservation work. For those of us in its migration path, protecting the Monarch remains a top priority. If we wait until it's an emergency, we may not be able to help this incredible species."

Reporters covering Monarch butterfly conservation are encouraged to reach out to press@fieldmuseum.org to interview Field Museum scientists who specialize in Monarchs and talk about the nuances of listing a species as endangered. Researchers are available for interviews in English, Spanish, and Polish.