In the last five decades, the number of monarch butterflies migrating to the Midwest from Mexico has declined by nearly 80 percent. More than 40 organizations are working to build back the population of these important polliantors.
While monarchs are not direct pollinators of corn and soybeans, the rebuilding of habitat for the monarch butterfly also provides habitat for pollinators who are very important to farming, such as bees, wasps and moths. Monarchs prefer to pollinate wild flowers, according to Steve Bradbury, Iowa State University professor of natural resource ecology and entomology. The Iowa Monarch Conservation Consortium began with conversations in 2014 before the first organized meeting in February 2015. The group has grown from the 20 original groups to over 40 organizations involved in the consortium.
“We have moved from the planning part to implementation of the plan,” Bradbury said. “Farmers have the ability to help monarchs because they have the land available.”
The Iowa Monarch Conservation Consortium is a community-led group whose goal is to increase reproduction and survival of the monarch butterfly through efforts of farmers, private citizens and organizations.
“The decline in monarch numbers over the years has come because of a loss in prairie and grassland, the loss of over-wintering habitat in Mexico, and intensive weed management killing milkweed, which is the only place monarchs lay eggs,” Bradbury said. “Monarch populations are getting so low that a severe weather event in Mexico, where they winter, could lead to monarchs not migrating back to the U.S.”
Numbers are analyzed in areas of Mexico where monarchs winter. Loss of the over-wintering habitat has been noticed by the Mexican government and Bradbury said efforts in that country are aimed at protecting those habitats.
“In Iowa, we have to build back the summer breeding habitat for monarchs,” he added.
The U.S. Fish and Wildlife Service is considering listing the monarch as a threatened species under the Endangered Species Act, indicating the urgency of implementing viable, voluntary monarch conservation programs to avoid a potential listing.
Ways to help
The consortium has identified five ways to help build back the habitat for monarchs in Iowa with hopes the surrounding states will follow suit.
The first is for farmers to take advantage of farm bill programs to establish monarch breeding habitat. Boosting milkweeds and nectar-producing plants in waterways and Conservation Reserve Program acres will help build a better ecosystem for monarchs and other pollinators like honeybees, plus wildlife including pheasants, according to Bradbury.
The second is to establish a monarch habitat on lands as part of a demonstration project.
“This can be done by farmers, citizens or communities. It can be a how-to area for others to learn from,” he said. As a part of this the Iowa Natural Heritage Foundation and partners, through the Monarch Butterfly Flyway Project, are restoring monarch habitat in three places along the migration corridors of Iowa.
The third is to follow federal pesticide labels and state regulations when applying pesticides. Bradbury said reducing pesticide drift will help prevent losses of monarchs.
The fourth is to consider monarch-friendly weed management recommendations for roadsides and right-of-ways. Milkweed and nectar plants are common in these areas and avoiding spraying or mowing will help maintain native plants.
Finally, the establishment of monarch way stations, or gardens with both nectar plants and milkweeds, can help monarch butterflies find nectar and reproduce.
“Monarchs lay eggs on milkweeds and milkweeds are the only plant monarch caterpillars eat,” Bradbury said. “It’s important to have these plants in small patches for monarchs to thrive.”
Habitat establishment and research
The establishment or reestablishment of habitat for monarchs doesn’t happen over night. Bradbury said it can take three to five years to establish a good habitat.
“Depending on what kind of place the habitat will be established, current vegetation may have to be killed first because it will cause too much competition with the native prairie grasses and milkweed,” he said.
Fall dormant seeding is recommended. Bradbury said the area will need to be mowed two or three times and then management becomes much easier, with mowing or burn-down practices every three to five years.
The updated Iowa Monarch Conservation Strategy seeks to establish 480,000 to 830,000 acres of monarch habitat by 2038.
“Iowa falls entirely within the monarch’s northern breeding core. This means that every patch of milkweed habitat added in Iowa counts, and Iowa is perfectly situated to lead the way in conservation efforts for the monarch butterfly,” said Chuck Gipp, director of the Iowa Department of Natural Resources. “The recovery cannot succeed without Iowa.”
Gipp said female monarchs lay eggs exclusively on milkweed plants so national efforts focus on establishment of new milkweed stems for conservation goals. However, habitat plantings are expected to include a diverse array of nectar species to provide forage for adult monarchs throughout their life cycle and seasonal migrations.
Continual research is being conducted at Iowa State University to advance the understanding of monarch butterfly ecology. Bradbury is leading the study, which has been funded through a $1 million grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture Pollinator Health Program.
“This project’s goal is to support development of practical, science-based strategies for increasing habitat of the monarch butterfly in combination with crop and livestock production in Iowa and the upper Midwest,” he said.
The ISU team of researchers will use indoor and field studies to develop a landscape-scale model of monarch movement and population responses. Researchers plan to use female butterflies tethered to instruments in a large facility used by Iowa State sports teams, and radio telemetry in the field, to measure the ability of monarchs to perceive and move to milkweed and flowering plants.
“Our current model results indicate we need to better understand the perceptual range of the monarch to improve our ability to predict how different arrangements of habitat patches in the landscape influence population responses,” Bradbury said.
Perceptual range is the distance at which monarchs detect milkweed or nectar plants in the landscape. It can be estimated from observations on how a monarch orients its flight towards a resource, like milkweeds.
The ISU team is working with researchers from the U.S. Geological Survey, who are developing a conservation model for the entire country. The Iowa State model will be applicable to the north central U.S.
Without the action of Iowa landowners to help the monarch habitats, it could become required. “If it becomes mitigation, The Endangered Species Act has tremendous impact on private land ownership. We don’t want to get at a point where there is no choice but to do this then it becomes mandated under the endangered species act. We’d rather have voluntary participation,” Gipp said.
It is a lot to ask a farmer to plant milkweed, which is a weed, so Gipp said poor quality land that wouldn’t grow crops well or a grass waterway to help prevent erosion would be good choices.
“With the implementation of more monarch habitats I think we will see a turn-around in populations very soon,” Bradbury said.
For more information about the reestablishment of monarchs, visit www.monarch.ent.iastate.edu or www.monarchwatch.org.
Jennifer Carrico can be reached at 515-833-2120 or [email protected].
