Monarchs, milkweed and migration
In December 2024, the U.S. Fish and Wildlife Service proposed that the monarch be protected under the Endangered Species Act.
By Mary Hightower
U of Arkansas System Division of Agriculture
Aug. 18, 2025
Fast facts:
- Milkweed necessary to monarch butterfly life cycle
- Native milkweed easy to grow
(1,251 words)
(Newsrooms: with album of art, art of Powers, monarch on milkweed, vertical of monarch on milkweed
With sidebar on ‘Methuselah monarchs’)
LITTLE ROCK — A pollinator admired for its beauty and migratory endurance, monarch butterflies are being proposed for addition as an endangered species. Some in Arkansas are supporting these highly recognizable insects as they migrate and breed.
In December, the U.S. Fish and Wildlife Service proposed that the monarch be protected under the Endangered Species Act. The public comment period for that proposal ended in May, said Brigit Rollins, staff attorney for the National Agricultural Law Center.
“We are waiting on final action,” she said. And with more than 81,200 public comments submitted, “it will take some time for FWS to get through them.”
The fragile-winged butterflies can endure migrations of thousands of miles each year, with eastern monarchs flying as far northward as Canada from their winter grounds in central Mexico. Western monarchs have a shorter trip, migrating from Utah and Arizona to coastal California for the winter.
“The monarch butterfly is a species that has declined significantly over the last 20 years,” said Jon Zawislak, assistant professor-apiculture and urban entomology for the University of Arkansas System Division of Agriculture.
“Arkansas lies within the migratory and spring and fall breeding area of their annual migration route,” he said. “A critical factor in their successful migration is the availability of food plants. While adults feed on energy-rich nectar, their caterpillars consume only leaves of milkweed, and therefore these are the only plant onto which adult monarchs will deposit eggs.”
According to the Xerces Society, monarch populations based in central Mexico have declined more than 80 percent since the 1990s while western monarchs, have declined more than 95 percent since the 1980s.
“Major factors include loss of overwintering habitat in Mexico due to illegal logging, climate change, and loss of suitable food plants — milkweed in particular for reproduction — but also general loss of wildflowers for adult food across their migratory route, due to changes in land use and pesticide use,” Zawislak said.
“Despite their reputation for sequestering distasteful compounds, there are several predators that do eat monarch larvae and adults. So, they serve as food for other critters,” he said.
The monarchs have another role in the environment.
“As pollinators, butterflies have no specific home like bees,” Zawislak said. “As they migrate across the landscape, they can genetically connect patches of flowers that are geographically distant. Their impact as pollinators is a little different than bees, which stay within a specific radius of their nests.”
Leslie Cooper, the Arkansas monarch and pollinator coordinator for Quail Forever, said that “the most important thing that every Arkansan can do to help monarchs and pollinators is by planting Arkansas native plants.
“Arkansas has 21 native milkweed species that tolerate a variety of conditions from full-sun to part-shade and dry to moist soils,” she said. Those who enjoy citizen science projects.
“can also join the Arkansas Monarch Mapping Project on iNaturalist and report their monarch sightings. They can also check out the Monarch Joint Venture website and learn about additional community science opportunities.”
Zawislak said some people capture and tag monarchs with tiny stickers printed with unique ID numbers.
In Mexico, locals find the tagged butterflies and log them, to give researchers “an idea of how many make the full journey, and from where they started,” he said. “But if you find one anywhere you can go online to report where it was.”
Details about tagging and reporting tagged butterflies can be found online.
Milkweed
Monarchs depend on milkweed: It’s the only host plant for monarch caterpillars. Monarchs are uniquely adapted to milkweed which contains compounds toxic to other animals. Female monarchs lay their eggs on milkweed and once hatched, the caterpillars eat the milkweed and store the toxins, which make them uninviting to predators.
Growing milkweed is a focus for Marty Powers, a Master Gardener who just retired from his work at the Shiloh Museum of Ozark History in Springdale.
“I really got into it pretty heavy in 2016 when we had planted a tray of milkweed from Monarch Watch at the Shiloh Museum,” Powers said. “I planted that tray of milkweed and the first year — instantly — we had caterpillars. It just kind of dawned on me: ‘Wow. This is pretty easy to get caterpillars. Why don't we plant more milkweed?”
He’s never looked back. Since 2016 the Shiloh Museum has given away more than 25,000 milkweed plants, including more than 4,500 this year alone.
“It's an incredible day to see all the energy. There's a lot of people really wanting
to help” the monarchs and other pollinators, he said. “And that kind of feeds us —
makes us want to do more.”
At his home, Powers has also planted several patches of milkweed to collect seeds
from mature and viable native varieties such as swamp, common, tuberosa or butterfly
weed and spider milkweed.
Growing milkweed
Milkweed is fairly easy to grow. Gardeners collecting their own seeds need to be sure the seeds are mature.
“They need to be brown and the seed pod is ready to pop open,” Powers said.
Milkweed seeds need a little moisture and cold to be ready to emerge in spring, through a process called stratification. Powers said the cooling process can be done in the wild, with seeds left on the ground starting in fall. However, to prevent critters from vacuuming them up, Powers puts his in the fridge.
He places seeds on top of paper towels that he soaks with water. Once the seeds are nice and damp, he bundles them into a zip-top bag and puts it in the refrigerator for 30 to 45 days.
Once spring arrives, they’re ready to plant, simply by scattering them on the surface of the ground.
Powers keeps his milkweed in a separate plot in his garden, but the rest of the garden is also planted for pollinators.
“I have all the native nectar plants — Joe Pye weed and purple cone flower” among others, he said.
For fall nectar, when the monarchs are on their southbound migration, Powers said he does “stray from the natives a little bit. The Mexican sunflower is a really, really great nectar plant for fall.”
Other fall bloomers that monarchs love include native goldenrods, blue mistflower and Arkansas ironweed.
Swamp milkweed tends to be a late-bloomer and good for southbound monarchs.
Since his retirement from the Shiloh Museum, Powers now grows milkweed at the Elkins High School green house.
Raising butterflies
Kathy Peek takes another approach to supporting monarch populations: she raises them. Peek said she’d always loved butterflies, but her appreciation for them deepened during photography club discussions.
“I realized they were endangered and so I asked, ‘what could I do?’” she said.
She decided to raise them, using restaurant takeaway boxes to house eggs she finds in her garden until they hatch, and about a half-dozen pop-up fabric cages for when the caterpillars are ready to metamorphose into butterflies — all with the help of a lot of milkweed.
Peek recalled seeing a monarch in Minnesota in October, clinging fast despite hard, cold fall winds. She was amazed that as “fragile as they are, how resilient they can be.”
Peek will be releasing monarchs during the Monarch Flight Festival in Springdale. This year’s event is set for Sept. 20 at Luther George Park in Springdale from 11 a.m. to 4 p.m.
She documents her efforts with monarchs on YouTube.
Flagship species
“A majority of people recognize monarch butterflies much more than they can identify other butterfly species,” Cooper said. “This is valuable because monarchs can be considered a ‘flagship species’ and may be used to raise awareness and efforts toward native plant and pollinator conservation.”
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About the Division of Agriculture
The University of Arkansas System Division of Agriculture’s mission is to strengthen agriculture, communities, and families by connecting trusted research to the adoption of best practices. Through the Agricultural Experiment Station and the Cooperative Extension Service, the Division of Agriculture conducts research and extension work within the nation’s historic land grant education system.
The Division of Agriculture is one of 20 entities within the University of Arkansas System. It has offices in all 75 counties in Arkansas and faculty on three campuses.
Pursuant to 7 CFR § 15.3, the University of Arkansas System Division of Agriculture offers all its Extension and Research programs and services (including employment) without regard to race, color, sex, national origin, religion, age, disability, marital or veteran status, genetic information, sexual preference, pregnancy or any other legally protected status, and is an equal opportunity institution.
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Media contact: Mary Hightower
mhightower@uada.edu