AMES, Iowa – Every fall, monarch butterflies fuel up on nectar from Iowa’s fall-blooming wildflowers before embarking on an extraordinary migration from North America to Mexico. But the pathways they take and how their travel is affected by weather and other factors have largely remained a mystery.
Quick look
From campus to Mexico, a group of 100 monarchs tagged and released from Iowa State’s campus can be monitored through the Project Monarch app, available on Google Play and the Apple App Store. New information will be used to help improve conservation efforts for the monarch butterfly.
Now, researchers are using advances in wildlife tracking technology to fill those gaps. A team of conservation scientists and ecology experts at Iowa State is using BlūMorpho tags, the lightest tracking devices available, to monitor 100 monarchs they’ve raised, or reared, over the summer.
Throughout September, the team released the butterflies from campus to join millions of other eastern North American monarchs on their journey south.
“The availability of small radio tags is a game changer,” said John Pleasants, emeritus adjunct associate professor in Iowa State’s department of ecology, evolution and organismal biology. “Previous tagging with small decals attached to the wings could only tell us if a butterfly made it to Mexico; it could not tell us the pathway it took. With these new tags, we can see its entire journey and how weather affects it along the way.”
The new tags take battery-life challenges out of the equation and instead offer near-real-time location data using Bluetooth technology that connects cellphones, tablets and computers in their area.
Katherine Kral-O’Brien and Mykayla Hagaman, who oversee the Iowa Monarch Conservation Consortium based at Iowa State, and Nathan Brockman, director of entomology at Reiman Gardens, teamed up over the summer to collect and raise monarch eggs and caterpillars under three separate conditions: entirely indoors, entirely outdoors and indoors only during the final larval stages.
They’ll compare flight data from 75 reared monarchs with 25 wild-caught monarchs to see whether rearing conditions affect survival or the butterflies’ ability to travel in the correct southwest direction during the roughly eight-week migration.
“There’s been a lot of debate around the best ways to help monarchs thrive. Should you bring them inside and rear them? And does that help or hurt them?” Kral-O’Brien said. “We’re excited to answer those questions.”
The study is part of a larger project with researchers at the University of Guelph in Ontario, Canada, who say collaboration across multiple locations is necessary to better understand and protect the population. The eastern North American monarch population, which ranges east of the Rocky Mountains into Canada and across the eastern United States, has declined by as much as 80%.
Many of the monarchs that reach the overwintering grounds in a small cluster of forests in central Mexico originate in the Midwest, making Iowa an important region for monarch production in North America, according to Pleasants, who connected the Iowa State team with the project in Canada.
“What we do here, as far as modifying landscapes to support monarch conservation, can have a big effect,” he said.
Through the Iowa Monarch Conservation Consortium, more than 690,000 acres of monarch habitat have been established across the state since 2015, benefiting other pollinators and the plants and ecosystems that depend on them. The organization brings together more than 50 groups dedicated to monarch conservation, including agricultural organizations, private companies and state and federal agencies.
Community volunteers from all 99 Iowa counties have also contributed to monarch conservation efforts. Many Iowans are familiar with the butterflies from grade-school science classes, where they watched their transformation from egg to caterpillar to butterfly.
“Because so many people have an emotional connection to monarchs, it’s a really great way to get more people involved,” Hagaman said. “Monarchs can really benefit from any size of conservation efforts – from large prairie plantings to pollinator gardens to a potted milkweed plant on someone’s porch.”
The public can help monitor the Iowa State monarchs’ migration through the Project Monarch app, available on Google Play and the Apple App Store. After enabling Bluetooth on their devices, participants can search for tagged monarchs in their area and submit their observations.
For Brockman, who was part of a team that tested the BlūMorpho transmitter last year in the Christina Reiman Butterfly Wing, the project is another opportunity to extend Reiman Gardens’ conservation work across campus.
“Playing with butterflies and insects is what we do here at Reiman Gardens,” he said. “We love the opportunity to share that experience across campus and work together to advance conservation.”
