What the monarchs are telling us

Friends of the Earth
Friends of the Earth Newsmagazine
5 min readJun 20, 2014


By Dana Perls, food and technology campaigner, and Tiffany Finck-Haynes, food futures campaigner

Each autumn, millions of gold and black Monarch butterflies begin their ancient 2,500-mile migration from Canada to Mexico—stopping in the vast Great Plains to lay eggs, and again in California’s central coast to rest—before spending winter in Mexico.

Normally, several generations of monarchs lay eggs on milkweed plants, on which the larvae will feed, grow and undergo metamorphosis. As adult butterflies, the monarchs migrate south to wait out winter; returning to their milkweed breeding grounds the following spring to continue the cycle.

Unfortunately, North America’s magnificent mass migrations may soon cease to exist. On the heels of recent global bee declines, the monarch butterfly is in serious trouble. In January, news outlets across the globe reported the number of monarchs arriving at their ancient overwintering grounds in Mexico reached the lowest level on record: a 44 percent decline, half the lowest number from the prior year.

Monarch caterpillars feeding on milkweed.
Photo credit: Vicki’s Nature, Flickr, Creative Commons

What are these small but important creatures telling us about the state of the planet? What we can do to save them, and in the process, ourselves?

More than 50 years after Rachael Carson’s Silent Spring, the seemingly trivial choice of how we manage our farm fields impacts not only butterflies and bees, but our health and that of broader ecosystems.

GMOs, Roundup and the vanishing prairie

The monarch’s sharp decline has been linked to a steep increase in the planting of GMO herbicide-tolerant “Roundup Ready” corn and soy crops and the accompanying increase in Monsanto’s Roundup (glyphosate) herbicide, which decimated milkweed, the only food young monarchs eat.

Over the last decade, more than a million acres of native grassland in the upper Midwest, which formerly provided habitat for milkweed, monarchs, and a host of other important species, have been destroyed. Surprisingly, this is done to make room for corn and soybeans, to meet a growing demand for biofuels and to supply feed for expanding factory farm livestock production.

Rates of native prairie destruction, and accompanying habitat and biodiversity loss, over the last decade have paralleled or exceeded rates of deforestation in Brazil, Malaysia and Indonesia. This is the fastest loss of these grasslands since tractors began “busting” Great Plains sod in the 1920s. These areas of native grasslands are critically important habitat to a large variety of important species, hold vast stores of carbon and are at extreme risk of erosion and drought.

In the last decade, the amount of U.S. crops genetically engineered to withstand massive applications of Monsanto’s patented Roundup herbicide grew to comprise 83 percent of all corn and 93 percent of soybeans. As a result, the use of Roundup skyrocketed. And this, combined with farmers plowing up former habitats and planting fence row to fence row, has virtually wiped out the milkweed that once grew between our farm fields.

Photo credit: Austin Valley, Flickr, Creative Commons

To facilitate greater pesticide use, Monsanto successfully petitioned the EPA in 2013 to raise the legally accepted tolerance levels of glyphosate residue on animal feed to a level five times higher than Europe’s. Tolerance levels for various fruits and vegetables were also raised and removed entirely in some cases. Milkweed cannot survive this onset of glyphosate. Researchers estimate that milkweed in Midwest farm fields plummeted by more than 58 percent over the last decade, while monarch egg production across the region sank by 81 percent.

The pesticide- GMO treadmill

Unfortunately, as farmers have planted more GMO herbicide-tolerant crops and doused their fields with Roundup, glyphosate-resistant “superweeds” have evolved. More than half of U.S. farmers have reported such weeds on their farms.

Instead of breaking this vicious cycle, agrochemical companies, including Monsanto and Dow, are doubling down in their chemical war on weeds and are preparing to introduce the next generation of GMO crops engineered to resist massive applications of even more toxic herbicides: 2,4-D and closely related dicamba.

Photo credit: tjmartins, Flickr, Creative Commons

The herbicide 2,4-D is one of the primary active ingredients in the banned Vietnam War-era defoliant Agent Orange, and it not only poses further threats to already compromised ecosystems and broad-leafed plants like milkweed, it also is a reproductive toxicant, a suspected endocrine disruptor and a probable carcinogen. Even more concerning, widespread planting of 2,4-D corn could result in as much as a 30-fold increase in 2,4-D use on corn by the end of the decade. No doubt weeds will soon evolve resistance to these herbicides, and no doubt agrochemical companies like Monsanto will have even more hazardous “solutions” at the ready.

Canaries in the coal mine

Bees, butterflies and other pollinators are responsible for producing more than two-thirds of global food crops. In the U.S., pollinators contribute to $20 billion in annual agricultural production. In addition, pollinators play vital roles maintaining healthy plant communities, which keep waterways clean, prevent erosion and help create food and cover for wildlife. Already there are almost 40 threatened or endangered species. We must keep monarch butterflies off of that list.

Monarchs are another “canary in the coal mine,” telling us that we need a rapid transition to sustainable, just, healthy ecological agriculture. Unfortunately, they are only the tip of the iceberg, and many scientists are concerned that we may be experiencing a second Silent Spring. A wide variety of pollinators and other insects, including many that benefit farmers, are also rapidly disappearing across America’s heartland, along with the birds, mammals and other predators that feed on them, due largely to the ravages of chemical-intensive industrial agriculture. Friends of the Earth and allies are working hard to get us off the dangerous treadmill that is harming these majestic pollinators, destroying essential ecosystems and threatening our health.

This article was featured Friends of the Earth’s spring 2014 newsmagazine. Read the full issue online here.



Friends of the Earth
Friends of the Earth Newsmagazine

Friends of the Earth U.S. defends the environment and champions a healthy and just world. www.foe.org