DEBBIE ELLIOTT, HOST:
One of the world's great migrations has begun. Eastern monarch butterflies are flying more than 2,000 miles south through the central U.S. to overwinter in Mexico. As Harvest Public Media's Rachel Cramer reports, they're getting some help from states planting rest stops along the way.
RACHEL CRAMER, BYLINE: In 2013, the number of eastern monarch butterflies sank to their lowest level on record. A census at the time showed that the number of monarchs that had once covered 50 square acres of forest in central Mexico, where they overwinter, had dropped to covering fewer than three square acres. Scientists warned monarchs would become extinct unless their numbers increased. The Obama administration formed a task force to figure out how to reverse the decline. A monarch butterfly expert came to speak with highway managers.
CHIP TAYLOR: In that talk, I presented an idea that we could improve monarch habitat by creating strips of milkweed and native plant habitat along the banks of the interstate highways.
CRAMER: That's Chip Taylor, the founding director of Monarch Watch at the University of Kansas. And he says there was one interstate in mind.
TAYLOR: I-35 runs from the northern part of the U.S., round Duluth, all the way down to the border in Texas.
CRAMER: The idea was called the Monarch Highway. The goal was to plant milkweed and other native wildflowers in areas along the interstate to offset habitat loss. The Federal Highway Administration signed an agreement with several state Departments of Transportation that manage I-35. However, the Monarch Highway project stalled, due in part to a lack of funding and changing priorities at the state and federal level. Still, some states have embraced adding milkweed and other wildflowers along roads. In Illinois, where the official state insect is the monarch butterfly, local governments, conservation groups and state agencies are working along a famous route. Susan Helm is co-president of the project.
SUSAN HELM: We realized that monarchs in Illinois travel up and down - basically along Route 66.
CRAMER: Helm offers lots of advice to groups that want to start native pollinator gardens, from seed mixes to maintenance.
HELM: There's a lot of interest. There's a lot of enthusiasm, whether it's a library, a park, even businesses, historic sites or Lincoln's home - Oak Ridge Cemetery, where Lincoln's buried. I mean, it's just snowballed in a good way.
CRAMER: The Route 66 Monarch Flyway runs between Chicago and St. Louis. There's a similar concept in Missouri with the nearly 300-mile-long Highway 13 Butterfly Trail. Iowa has been reintroducing native plants along roadsides for decades. Rachel Harris is the chief landscape architect in roadside development for the Iowa Department of Transportation. She's excited to point out all the different wildflowers growing next to an I-35 exit.
RACHEL HARRIS: There's obviously the compass plant. But there's also the false indigo, baptisia, rattlesnake master.
CRAMER: Back in the 1970s, Harris says Iowa spent a lot of money mowing nonnative grass and spraying weeds alongside highways. The current approach is less costly, both for the state's budget and the environment. And Harris says those prairie plants, of course, provide habitat for monarch butterflies.
HARRIS: I love coming out here and seeing all the butterflies and the bees. Every time we see monarchs, like, our team will be like, monarch (laughter) 'cause we always get really excited.
CRAMER: A monarch butterfly flies by, as if on cue. Experts like Chip Taylor with Monarch Watch say these butterflies face a lot of threats, especially with climate change. But having areas where they can eat, rest and lay their eggs gives monarch butterflies a greater chance of completing their migration.
For NPR News, I'm Rachel Cramer in Des Moines, Iowa.
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