Saving the Monarch Means Saving the Prairie — and Agriculture

by Laura J. Jackson


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In the winter of 1995-1996 the overwintering colonies of monarch butterflies in the Oyamel fir forests of Michoacan, Mexico, measured almost 20 hectares. On almost 50 acres of forest, each branch of each tree was loaded with layer upon layer of butterflies. Over the next 20 years, the size of the overwintering colonies fluctuated widely around a mean of six hectares. Then in the mid-2000s the colonies began to shrink, hitting an all-time low of 0.67 hectare (1.6 acres, less than the size of a city block) in the winter of 2013-14.

The subsequent summers in the Midwest have been full of watchful anxiety, as people in the prairie states—the monarch’s summer breeding ground—waited for the first sightings of migrants flying north from Oklahoma and Texas in late May to lay eggs on wild milkweed plants. Here generations two and three would quickly grow, mate, lay eggs and die within six to ten weeks, building up population numbers. The fourth generation—dubbed the “supergeneration” for its nine-month lifespan and enormous feats of migration, would delay sex, fatten up on nectar from late summer wildflowers, and fly to Mexico. Then in spring, the survivors of that journey would return to Texas to mate and lay eggs.

There were several hypotheses concerning the causes of monarch decline, including bad weather, habitat loss in the Mexican highlands where they overwinter, exposure to pesticides, natural diseases, and habitat loss in the breeding range of the upper Midwestern U.S. Pleasants and Oberhauser (2013) published a paper regarded as providing “smoking gun” evidence linking the monarch population decline to increased adoption of herbicide-tolerant varieties of corn and soybeans. The data from 1999 showed abundant common milkweed (Asclepias syriaca, the monarch butterfly larva’s obligate food) in the 73 million acres of U.S. corn and soybean fields, and virtually none ten years later. A subsequent paper by Thogmartin et al. (2017a) came to the same conclusion, using different methods. Although a few studies have disputed this conclusion (e.g. Inamine et al. 2016), their methods have been convincingly challenged (Pleasants et al. 2017).

A simple winter storm that year could have wiped out every monarch in eastern North America.

Those 73 million acres of fields had once made an excellent nursery for monarch caterpillars. Widespread concern arose that eliminating milkweed would greatly reduce the monarch population. It’s a concern that has been borne out. At first, declines in monarch numbers were met with a wait-and-see attitude, since in the past the monarch had bounced back as much as 500 percent from years of poor weather to average years. However, in the winter of 2012-13, wildlife biologists finally stopped watching and sounded the alarm when the number of monarchs overwintering in Mexico reached an all-time low, with the entire population fitting into fewer than two acres. A simple winter storm that year could have wiped out every monarch in eastern North America.

Today, broad-scale efforts to protect the iconic monarch are being undertaken by numerous state and federal agencies, agribusiness corporations, private citizen groups ,and nongovernmental organizations. Can these efforts succeed? The stakes are high: the loss of a beautiful and utterly harmless creature whose compelling, near-miraculous migration story is familiar to millions of Americans. Along with this catastrophe would go the loss of uncounted other vulnerable insect species as well.

The fight to ensure the monarch’s future raises fundamental questions about the history and the future of the tallgrass prairie region. Will our agricultural system allow this native species to persist as a wild, self-reproducing population? Or, will monarchs follow the many other species in the prairie region which have fallen under the shadow of extinction or disappeared entirely into it—the passenger pigeon, the prairie chicken, the bobolink and other grassland nesting birds; the black bear, wolf, cougar, elk and bison, the many large migratory wading birds that used to nest in the wetlands amid the cornfields; and perhaps even the commercial honeybee? If monarch butterflies are lost, could other abundant and ubiquitous animals, such as lightning bugs, or the American Robin, face a similar end?

The decline of the monarch butterfly is best understood in the context of agricultural industrialization. The processes which threaten this most resilient of Midwestern creatures have created other seemingly intractable problems in our communities and in our ecosystem—the persistent and growing Dead Zone in the Gulf of Mexico, the nitrogen and phosphorus contamination of rivers and sources of drinking water, the increased frequency and intensity of flooding, the usurpation of local elected government function by agribusiness interests (revelations for which Art Cullen, the editor of the Storm Lake Times, received a 2017 Pulitzer Prize in editorial writing), and the economic and social decay of rural communities. All these problems have been framed as necessary costs in the struggle to feed the world. Midwesterners have learned to live with them, and even to embrace them. Some say these sacrifices are a sacred duty, or dues which must be paid if we are to benefit from our region’s productivity. By sacrificing environmental quality and biodiversity here—the argument runs—we can boost yields and feed a starving child, or spare a rainforest somewhere else. This doctrine, known as “sparing land for nature,” has become a central trope in our region—and indeed in all regions touched by industrial agriculture—used by chemical and seed companies such as Monsanto to frame as intractable problems which are in fact mostly political and, therefore, quite tractable after all.

Regulation and accountability for results are never mentioned in polite company. Blind hope and unrealistic expectations stand in for a plan based on sound science, because our agricultural system has been too politically powerful and poorly understood to question.

It should be no surprise that the emerging strategy to increase habitat for the monarch in its Midwestern breeding range has been running into the sorts of roadblocks that caused the 30-year effort to address the Dead Zone in the Gulf of Mexico and the quality of surface water in the Midwest to fail. Measures on private land are voluntary, reliant on government (taxpayer) funding, and inadequate in the face of the problem they are supposed to address. Regulation and accountability for results are never mentioned in polite company. Blind hope and unrealistic expectations stand in for a plan based on sound science, because our agricultural system has been too politically powerful and poorly understood to question.

Monarch butterfly decline, and the reaction

The decline in the monarch’s population made a splash. In response, in spring 2014, President Obama issued a Memorandum called “Creating a Federal Strategy to Promote the Health of Honey Bees and Other Pollinators” (Obama, 2014). This document called upon U.S. federal agencies involved in any sort of land management to develop a strategy for creating new habitat, by summer 2015, using existing resources. The Bureau of Land Management (BLM), the U.S. Forest Service (USFS), the National Park Service (NPS), the Natural Resource Conservation Service (NRCS), the U.S. Department of Transportation (USDOT), and the U.S. Fish and Wildlife Service (USFWS) all scrambled to come up with plans. For instance, The USFWS announced the creation of a Monarch Highway, a 100-mile-wide band centered on U.S. Interstate I-35, from Minnesota to Texas.

Then in 2015, a group of scientists and conservation organizations, led by the eminent monarch biologist Lincoln Brower, petitioned the USFS to put the Monarch butterfly on the Threatened Species List. After initial review, the petition was deemed reasonable, which put the USFWS and major stakeholders on a timetable. By June 2019, the agency would have to weigh evidence and make a decision. A decision to put monarchs on the threatened species list would have vast repercussions. It would become illegal to harm the species in any way, including through harm to its habitat. Common land management actions, such as mowing or grazing at the wrong time, or converting a conservation area back to row crops, could trigger a fine. In short, endangered species status for the monarch could theoretically paralyze economic activity in the U.S. Corn Belt and force unprecedented regulation on every landowner and tenant/operator.

Another response to the shockingly low number of monarchs overwintering in 2013-14 was a scientific effort to determine, first, an estimate of the target population of monarch butterflies that would be stable, long-term and not likely to go extinct, and, second, the total number of new milkweed plants that would be needed to reach that population target. Scientists with the USFWS arrived at a target of six hectares of monarchs in Mexico, and to achieve this target, various estimates of the amount of new milkweed stems needed range from 1.3 to 1.8 billion (Pleasants 2017).

Also in response, several major efforts are under way to plant more milkweed and nectar plants:

• The Monarch Joint Venture, formed in 2009, coordinates government and private partners “united in an effort to conserve the monarch migration.” Their North American Monarch Conservation Plan has become a blueprint for research, education and habitat restoration, and the partnership has swollen quickly from just a dozen to over 70 groups nationally, as more local, state and federal partners join the group.

• The seed and pesticide company Monsanto, which originally introduced glyphosate/herbicide tolerance technology, established a fund through the National Fish and Wildlife Foundation of $4 million to support recovery efforts. Much of the funding in 2016 went to projects in urban areas and transportation rights-of-way. Monsanto and other major seed and chemical companies such as Dow, DuPont and Syngenta also co-fund other efforts to create habitat such as the Bee and Butterfly Habitat Fund. This group, which includes the companies that provide pollination services to to vegetables and fruit trees, seeks to turn underutilized acreage into productive precision habitat to help save pollinators. Landowners receive free seed, three- to six-year contracts, planting incentives and annual rental payments.

• Every state in the tallgrass prairie region either is developing or has already announced a Monarch Recovery Plan. In Iowa, the Monarch Conservation Consortium—composed of 30 groups in all and organized by Iowa State University. with membership from major farm and agribusiness sectors—is developing a strategy that focuses on adding milkweeds to roadsides, urban areas, and already protected public lands. Separately, the U.S. Fish and Wildlife Service is coordinating a national plan for monarch recovery that relies on the same mix of strategies, plus existing Farm Bill conservation programs (Conservation Reserve Program, etc.)

• The public passionately wants to be involved. There has been an explosion of interest in planting milkweed in home gardens, and on the grounds of schools, churches and corporate campuses. Many organizations such as Wild Ones, and Plant. Grow. Fly have been facilitating these efforts. The organization Monarch Watch, based in Lawrence, Kansas, grows and distributes several hundred thousand milkweed plugs to individuals to create small monarch waystations across the country. Monarchs in Eastern Iowa distributes over 50,000 milkweed seed balls, each one containing four seeds, to riders each year in the Register’s Annual Great Bike Ride Across Iowa. (RAGBRAI) The Monarch Research Project rears caterpillars and releases them, while working with the City of Cedar Rapids, Iowa, to convert 1,000 acres of turfgrass to wildflower plantings.

All rescue efforts propose to do the same things: plant milkweed and nectar-producing plants on public and urban land, and modify existing farmland conservation programs that were designed primarily for severe soil and water conservation problems. More fundamentally, they assume that the market and policy incentives now encouraging our current vast areas of row crops are permanent, and that conservation practices on private land will continue to be completely voluntary.

This may be politically realistic, but is it scientifically realistic? A recent study by Wayne Thogmartin and others (2017a) used geospatial modeling and expert opinion to estimate potential land area, adoption rate and numbers of new milkweeds that could be added to five different sectors of land cover: protected area grasslands, lands enrolled in the U.S. Department of Agriculture’s Conservation Reserve Program, urban/suburban lands, rights of way, and agriculture. The authors calculated low, medium and high estimates of milkweed gain in each sector, and examined every two-, three-, four- and five-sector combination for a total of 218 scenarios. Sixteen scenarios met the minimum target of 1.3 billion milkweed stems thought necessary for a sustainable migratory population. All of the successful scenarios included conversion of at least six million acres of agricultural land in the U.S. now devoted to row crops such as corn and soybeans, to grasslands. To put it another way, even in the most optimistic scenarios with highest levels of participation, the model failed unless it included agriculture.

This disappointing result is primarily because the footprint of non-agricultural areas is relatively small, but additionally because other non-agricultural areas already contain significant amounts of natural milkweed (e.g. along railroad tracks), or adoption rates are expected to be limited (urban/suburban areas), or both.

Urban monarch supporters have challenged this conclusion, and the estimates for contributions of urban/suburban homeowners may in fact be too low. But few urban people drive the gravel roads in the heart of the monarch breeding zone, through the miles of solid corn and soybean fields, for hours on end. It’s a common and natural fallacy to extrapolate from one’s personal experience of abundant milkweed—in backyard gardens, roadsides, parks and schools—to the whole world. An individual’s observations along familiar routes are misleading: they sample only the thin belt of land on either side of a road, but not the large interior spaces beyond. And they do not sample rural America’s vast unpeopled spaces.

Roadsides are a popular target for new habitat, but in order to increase milkweed stems in these areas, state departments of transportation would need new tools, new training for staff, and an entirely different mindset to give up frequent mowing and plant more diverse habitat. Conversion of roadsides to suitable habitat is not simple. Iowa is unique in having a provision in state code declaring it to being in the public interest for roadsides to be managed with ecological goals in mind. After 25 years of state and federal incentives—equipment, coordination, research and free prairie seed—only 44 of Iowa’s 99 counties have chosen to hire a full time roadside manager. Many of the barriers to converting public rights-of way are not appreciated by the general public.

General audiences and scientists alike are powerfully drawn to images of hope: a photo of children releasing hundreds of tagged monarchs from a backyard garden certainly gives one hope. And the vision of children releasing hand-reared butterflies should inspire hope. But, hope for what?

Humans have the capacity to feel affection for, and to lavish care and attention on, a wild animal such as the monarch. We have the ability to learn about and then spread awareness concerning the threat the monarch is under. But the source of hope should not be the number of butterflies the children release; it should be the children themselves—deeply affected by their experience, and moved to become advocates for meaningful public policy. Equally, our hope—indeed, our faith—should lie in the ability of plants and animals, given a chance, to go about their business every day, busily reproducing and multiplying, completely untended. These are the processes, combined with plenty of habitat, that produce billions of milkweed plants year after year, and millions of monarchs.

Public involvement will be an effective tool for monarch recovery when it results in advocacy for policies that support wild populations. It will undermine our efforts if it is entirely focused on the satisfaction of raising a few caterpillars. When NASA was trying to put a man on the moon, it had incredible support from taxpayers. Some of NASA’s budget went to public engagement programs which sustained political support for the program. Some money went to engineers to figure out how to accomplish the agency’s aims. But the public was never asked to do the engineering. Public engagement fueled political and economic support for the program. NASA-pin-wearing children helped build our rockets, not because they were engineers, but because they influenced their taxpaying parents to continue support for the space program. Planting milkweeds and rearing butterflies are great activities, but they should not be seen as an effective substitute for policy change.

A better approach to monarch conservation

If we are truly committed to helping the monarch to recover, there are two approaches we will need to take. First is formulation of a long-term strategy that focuses on changing farm policy. Second is effective habitat monitoring to support our awareness of the root causes of monarch decline. In the short- to medium-term, there are some pragmatic tactics we can use to engage and mobilize large-scale forces rather than diverting time and money to token, symbolic efforts.

Changing farm policy. Monarch conservation groups should approach the national and regional organizations that promote farm policy reform and offer to join forces. In this connection, we can learn something from the Union of Concerned Scientists’. proposal, Subsidizing Waste: How Inefficient U.S. Farm Policy Costs Taxpayers, Businesses, and Farmers Billions (Mulik 2016) The proposal begins with the idea that taxpayers should expect some accountability for their support, and that federal farm policy should not subsidize water pollution only to patch up the problems with a few conservation programs. It favors two main changes in agricultural practices for the upper Midwest. The first is the (modernized) return of integrated crop-livestock systems with grazing by ruminants and long (four or more year) crop rotations that require little or no herbicide or nitrogen inputs and result in more perennial vegetation in the ground at any given time. The second change would be planting 10 percent of fields with 30-foot-wide strips of tallgrass prairie wrapped around the contour of the slope. These prairie strips reduce surface runoff, slow the movement of soil downhill, reduce nitrogen and phosphorus losses, and increase habitat for wildlife. (The Tallgrass Prairie Center at the University of Northern Iowa is helping farmers to do this in the Cedar River watershed.) The Union of Concerned Scientists also urges environmental accountability, proposing that any farmer who wishes to receive federal farm subsidies such as crop insurance should be required to prove he or she is following a tailored conservation plan on their farms. These programs would still involve incentives, but the threat of having subsidies taken away for lack of compliance to conservation plans would create a powerful stick as well.

Along with this would be pursuit of greater accountability in the rest of the value chain for support of conservation. This approach begins with the assumption that the corporations supplying most of the inputs to farming—seeds, pesticides, fertilizers, loans, equipment—should shoulder some of the burden of conservation, along with the primary processors, such as grain processors and livestock feeders. Properly focused, large scale public concern for monarch conservation could eventually compel corporations to do this.

The large numbers of urban and suburban people who have come to love monarch butterflies also have a crucial role to play in promoting better agricultural practices. There’s enormous potential for a powerful political partnership between the “monarch constituency” and the host of sustainable agriculture organizations lobbying for changes to the farm bill.

Effective habitat monitoring. This second part of a changed approach to monarch recovery would involve rigorous monitoring of what we accomplish. Such accountability for measurable results is difficult to pursue and is usually the first thing to be dropped in any restoration program. Most restoration programs are “hit and run,” meaning that after an area is planted and the fanfare is over, everyone declares victory and leaves. Instead we need to measure the effort’s success or failure and adjust our plans and next steps accordingly. We need to hold entities accountable for what they say they have planted, for how much new habitat they have created, and for how long this augmentation of habitat lasts. The stakes are high, and thus it will be tempting to paper over failures and exaggerate successes. With the threat of endangered species status, there is incredible pressure to show that sufficient habitat is being created or protected so as to render listing unnecessary. For the sake of the monarchs, it is important for us to insist that we gather and respond to accurate data.

Short- to medium-term strategies

In addition to these long-term strategies, we need to do something now to increase habitat for monarchs as well as for other pollinators, particularly in the most intensively farmed areas of the Corn Belt. This is the dilemma: how can we make measurable change on a large scale when farmers are tied to existing conditions and barriers?

[T]hey are trapped in a system which incentivizes waste and does not reward conservation.

First, conducting research on natural regeneration of milkweed in the existing landscape would yield relatively large dividends. We need to know how the existing milkweed plants got where they are, and where and how our management practices can encourage them to spread. While it still makes sense to seed other species of prairie milkweeds such as butterfly (Asclepias tuberosa) and swamp (Asclepias incarnata) milkweed and nectar plants in places where they are sparse or absent, it makes little sense to do this with common milkweed. Although it has been banished from corn and soybean fields, we are lucky that common milkweed can still reproduce and spread naturally, on field margins. It is far more important—and would be less expensive—to discover how to “uncover” new populations through favorable management practices.

Second, we should target education and demonstration projects, aiming them at large-scale land managers and their crop consultants. Land management companies increasingly determine agricultural practices on lands owned by investor groups or out-of-state absentee landlords (approximately one-quarter of farmland in Iowa). The professional land manager’s primary goal is to help the landowners achieve their goals. Often, this means they are trapped in a system which incentivizes waste and does not reward conservation. However, soil erosion eventually cuts into income potential and land values. Landowners and land managers may be willing to address soil erosion in a way that also improves farm biodiversity.

For investors interested in conservation as well as income (up to 57 percent of farmers in one recent survey by Hertz Farm Management, a large company in eastern Iowa) there are opportunities to help farm management companies meet investor goals. The Tallgrass Prairie Center’s Prairie on Farms program has collaborated with professional farm managers, their tenants, and their investors, to establish demonstration prairie strips on vulnerable land. We are gathering data concerning these hands-on projects to share with others in the industry. Our prairie strip field days regularly include attendees whose decisions affect thousands of acres of farmland.

Organic farmers and those with alternative practices are important too, and we should reach out to these individuals and groups to find opportunities for collaboration. Many will be growing crops that require pollination services, such as fruits and vegetables. Many are likely to have forage and pasture land. This group is not using harmful insecticides such as neonicotinoids, which compromise the value of planted habitat. However, their footprint is still extremely limited, and they remain surrounded by high intensity, conventional corn and soy production.

Still another focus for these efforts could be land whose production value is marginal due to dry, wet, or damaged soil. It may be a high priority for land managers to find ways to put this land into other uses. Most now have the tools to identify these areas, and calculate a potential profit in taking land out of production (at least until grain prices rise again).

Finally, we should improve the federal conservation programs such as the Conservation Reserve Program (CRP, a program of the USDA Farm Services Agency), to include more diverse and cost-effective seed mixes and practices for a broad array of ecosystem services. There are several specialized programs for pheasants, quail, water erosion, and pollinators. The Thogmartin et al. (2017b) study cited above demonstrated that CRP land could only provide a small fraction of the needed milkweed stems, so it is important to make the most of these lands. If we can shift farm policy to favor more agricultural grasslands on the landscape, today’s CRP fields could form the foundation for rotational grazing and hay production, biomass energy production, and other sustainable farming practices that naturally favor habitat for monarchs. The Tallgrass Prairie Center is investigating seed mixes and systems for assuring appropriate species and sources of seeds that will deliver diverse ecosystem services while controlling costs.


The fate of the monarch butterfly is linked to every other conservation issue associated with industrial agriculture in the Midwest. If we continue to avoid an honest reckoning, the monarch will fare no better than grassland nesting birds, our rivers and drinking water supplies, rural communities, or the Gulf of Mexico. These sacrifices were not inevitable and can be reversed. The widespread popularity of the monarch butterfly presents us with an unprecedented opportunity to welcome a new group of urban advocates for farm and food policy that, in line with Aldo Leopold’s vision, “changes the role of Homo sapiens from conqueror of the land-community to plain member and citizen of it”. (1949) Like any true community, what benefits one member, ultimately benefits us all. Saving the monarch migration will require us to convert large areas of row crops back to diverse perennial grassland, and this will have uncounted benefits for soil, water, biodiversity; that is the ecosystem as a whole. Rootstalk leaf-bug icon marking the end of the article's text.

About Author Laura J. Jackson
Portrait image of author Laura J. Jackson.
Photo courtesy of Laura Jackson
Laura Jackson is Director of the Tallgrass Prairie Center and Professor of Biology at the University of Northern Iowa. She received her bachelor’s degree in Biology from Grinnell College and a Ph.D. in Ecology from Cornell University. Her research has focused on the conservation of biological diversity in agriculture landscapes and processes governing seedling establishment in tallgrass prairie restoration. In 2002, she and coeditor Dana Jackson brought out The Farm as Natural Habitat: Reconnecting Food Systems with Ecosystems, published by Island Press. The Tallgrass Prairie Center restores prairie for the benefit of society and the environment through research, education, and technology transfer.