Butterfly Highways: Conserving Roadside Habitats for Monarchs and Pollinators

The National Wildlife Federation’s Mayors’ Monarch Pledge program came together with the Texas Department of Transportation–Pharr District, Maramec Spring Park, Conservation Federation of Missouri, the James Foundation and the Missouri Department of Conservation to support the expansion of roadside habitat for monarchs and other pollinators. Learn from those in the Lower Rio Grande Valley and Missouri who implemented successful roadside habitat projects through our new video:

Supported by the New York Community Trust and in collaboration with diverse partners, this work resulted in the restoration of 78 acres across roadsides in the Ozark Highlands of Missouri and the Lower Rio Grande Valley of Texas.

Roadside Vegetation Can Address Monarch Butterfly and Pollinator Decline

One of the best strategies to support monarchs and other pollinators is to create ecological corridors along roadsides that will provide monarchs with food sources as they make their way along  the Central Monarch Flyway. This migratory corridor  stretches from the Monarch Butterfly Biosphere Reserve in Michoacán, Mexico, north through Texas, to the key breeding habitat in the Midwest and Great Lakes.

The monarch butterfly is an awe-inspiring North American species that has captured the imagination of millions of Americans. The eastern population of this impressive tiny and colorful insect makes a multi-generational 3,000-mile migration, traveling south to Mexico each fall and back up as far north as Canada in the spring. West of the Rocky Mountains, the western population migrates and overwinters primarily in coastal California each fall.

monarch butterflies
Credit: Kim Leahy

Both the western and eastern monarch populations have experienced significant declines. Less than five percent of the western monarch population remains, while the eastern population has fallen by as much as ninety percent. Monarch scientists attribute the population decline to degradation and loss of summer breeding habitat in the U.S., and loss of overwintering habitat in south-central Mexico and coastal California.

Habitat connectivity is essential to sustain the monarch butterfly population’s migration and survival. Vegetated roadsides with native plants provide host and nectar plants for monarch butterflies and many other pollinator species. Studies have shown that well-managed, high quality roadside vegetation increased butterfly species-richness and reduced the incidence of road crossing to seek sources of nectar—thus lowering road mortality.

Locally Driven Monarch Conservation

This work takes the dedication and support of diverse stakeholders like local municipalities, parks departments, planning departments, transportation departments, public works departments, land trusts, businesses, and numerous individual homeowners.

birds eye view of Highway 8 in St. James Missouri.
Highway 8 in St. James Missouri. Credit: Wesley Swee

The James Foundation owns and operates Maramec Spring Park, which is around 1,800 acres in size and home to the 5th largest spring in the state of Missouri. The James Foundation started its pollinator initiative in 2019 and has successfully planted 34 acres of monarch habitat along highway 8 and at Maramec Spring Park. Through their initiatives, they’re working to encourage and inspire local residents, homeowners, and students to plant wildlife habitats in their community that can support the monarch butterfly.

“As a conservationist, I knew that we had a lot of potential to convert local roadsides into habitat that could provide more benefit to the local ecosystem, especially monarchs and other pollinators,” said Wesley Swee, Director of the James Foundation. 

Pale-banded Crescent
Species like the Pale-banded Crescent (ruellia) are native to south Texas and would benefit from increased ecological corridors along roadsides. Credit: John Brush, Quinta Mazatlan Birding Center

Grassroots efforts and local leadership is integral for monarch and pollinator conservation and roadside habitat restoration projects. Through our work we have restored a total of 44 acres of roadsides in Texas.

“The Texas Department of Transportation is excited to continue investing in monarch conservation. We have signed the federal nationwide Monarch Butterfly Candidate Conservation Agreement with Assurances and have committed to supporting monarch habitat across approximately 410,000 acres of roadside. This agreement supports a variety of pollinator species, especially the monarch butterfly, by supporting and enhancing nectar resources along roadsides,” said Juan Sustaita, Pharr District, Director of Maintenance, Texas Department of Transportation. 

City and local leaders can reach local biodiversity, climate resilience, or other wildlife conservation goals by creating quality native habitats along roadsides. These actions have a proven ability to reverse monarch decline in North America.

If you are interested in roadside habitat restoration work, please read our newest publication, “Roadside and Pollinator Habitat: A Guide for Communities” for more detailed information and case studies that highlight how partners can implement a successful project.

If you want to support monarchs and other pollinators at home, consider joining the Community Wildlife Habitat program and join a network of dedicated volunteers. Check out Garden for Wildlife for more resources on how to create wildlife habitats at home or in your community. For more information on monarch conservation and to get involved locally, please visit our Mayors’ Monarch Pledge site and encourage your mayor to protect monarchs. Watch and share our newest video highlighting this grassroots effort, here.