JUANA SUMMERS, HOST:
Today, the U.S. Fish and Wildlife Service proposed listing the monarch butterfly as a threatened species under the Endangered Species Act. If approved next year, the monarch would become one of the most widespread species to receive such federal protections. Here with more is NPR science correspondent Jonathan Lambert. Hey, there.
JONATHAN LAMBERT, BYLINE: Hi, Juana.
SUMMERS: So Jonathan, just start by telling us what this decision means.
LAMBERT: Yeah. So under the Endangered Species Act, a species gets listed as either threatened or endangered. Endangered species are close to extinction and so get all sorts of automatic federal protections. Like, you can't kill an endangered species, and you can't do certain harmful activities on habitat that they might need to survive. Today, the government is proposing to list the monarch as threatened, which means it's at risk of becoming endangered, but not quite there yet. That gives the government a little more wiggle room to tailor the protections that a species gets. In this case, monarchs got a lot of wiggle room and some pretty broad exceptions, especially for agriculture.
SUMMERS: Got it. OK. Can you remind us why some people say the monarchs need these sorts of protections?
LAMBERT: Yeah. So Monarchs have this really remarkable lifestyle, where they take these long-distance migrations over the course of several generations, some traveling thousands of miles between breeding sites and overwintering sites. That means they're found in almost every state, so they're not super rare. But over the past few decades, their numbers have dropped by about 80- to 95%, and the Fish and Wildlife Service says that puts some populations at a high risk of extinction by 2080.
SUMMERS: OK, that sounds like a really big drop. Why are they in so much trouble?
LAMBERT: Yeah. There are three big factors - habitat loss, pesticide use and climate change. Monarchs need milkweed to fuel their long-distance migrations, and there's just a lot less milkweed than there used to be, mostly because of agricultural expansion. Pesticides can harm monarchs, too, and deforestation has shrunk many overwintering habitats. On top of all that, climate change is now a major threat and is disrupting ecosystems all along their migratory path.
SUMMERS: You mentioned that they're proposed as threatened, not endangered, and that this decision has a bit of wiggle room. How would listing them as threatened help?
LAMBERT: Yeah. So this proposed listing protects some key habitats along California's coast, and it would require people to get permits to develop native grasslands or forests if that development would kill monarchs. But across a lot of the butterfly's range, many things wouldn't change all that much. If you're driving down the highway and happen to hit a monarch, don't worry - you won't be committing a crime.
SUMMERS: OK. Got it.
LAMBERT: And agriculture got big exemptions, too, so a farmer doesn't have to worry about clearing milkweed on their fields. That said, the government might take more action on limiting certain pesticides in the final decision.
SUMMERS: What kind of reactions have you been hearing to this?
LAMBERT: Yeah. The biologists I've spoken with are really excited. They're still poring over the details, but they largely think the proposed listing will help monarchs without being overly restrictive on a species that's so widespread. And they also hope this energizes efforts to protect monarchs - everything from state conservation plans to just growing milkweed in your backyard, which can actually make a difference.
SUMMERS: OK, Jonathan, what comes next?
LAMBERT: So the public has until mid-March to comment on the proposed listing, and then the Fish and Wildlife Service will work on drafting a final rule, which could take about a year. But some conservation advocates worry that the incoming administration could weaken the power and scope of the Endangered Species Act, as they did the last time around, and that could ultimately throw the monarch's status into limbo.
SUMMERS: NPR's Jonathan Lambert, thank you so much.
LAMBERT: Thank you.
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