All About Monarchs: The Royals of the Butterfly World

Famous for their elegant colors and transcontinental feats of migration, these beloved pollinators are also in free fall, as habitat loss and heavy use of herbicides jeopardize their future.

The Migration and Importance of Monarchs

Monarch butterflies, which pollinate many different kinds of wildflowers, are among nature’s great wonders. Their annual migration is one of the most awe-inspiring on earth: Each fall, millions of these striking black-and-orange butterflies take flight on a 3,000-mile journey across the United States and Canada to wintering grounds in Mexico’s Sierra Madre mountains.

The Population Plummet

The monarch population, which is determined by measuring the number of hectares the butterflies occupy in their Mexico habitat, has declined to 2.48 hectares—almost 30 percent less than last year’s population. The population has been in steady decline for the past 20 years—reaching a high of more than 20 hectares in 1997 and plunging to 0.67 hectares in 2014. Two decades ago, nearly one billion wintering monarchs blanketed the mountain forests of Mexico. Today, that number has dropped by more than 80 percent.

Herbicides and Milkweed

Heavy use of an herbicide called glyphosate (marketed by Monsanto as Roundup) has greatly diminished milkweed, a native wildflower that is the sole food source for monarch caterpillars and the only plant on which adult monarchs lay their eggs. As milkweed disappears, monarch populations have also plummeted, and the annual migration of monarchs to Mexico is in danger of collapse. And yet the U.S. Environmental Protection Agency recently reapproved the registration for Dow’s Enlist Duo, a combination herbicide designed to kill milkweed.

Tell the EPA to protect monarchs from toxic herbicides

Solutions?

Much effort has gone into planting milkweed throughout the continental United States in the past several years in an attempt to make up for the milkweed that has been lost through agricultural practices. Planting milkweed is a great way to help other pollinators, too, as it provides nectar to a diverse suite of bees and butterflies.

But this year’s monarch butterfly population demonstrates that we need to do much, much more if we are going to be successful at building its population back up again to secure numbers. We also need to curb the use of pesticides that are eliminating milkweed in the first place and come up with sustainable solutions—not just for butterflies, but for farmers and our public health.

How NRDC Is Helping Secure a Healthy Future for Monarchs

NRDC envisions a future where monarch populations across North America are healthy and resilient. To achieve this, we’re working at the federal, state, and international levels to secure limits on the use of toxic herbicides and create new milkweed habitat.

We’re taking legal action against the EPA to win restrictions on toxic herbicides, such as glyphosate, that are killing off native milkweed. And we’re calling on agribusiness companies to withdraw their toxic products. At the state level, we’re working with officials to plant new milkweed habitat along the monarchs’ migration route. Internationally, we’re leveraging pressure by petitioning UNESCO’s World Heritage Committee to upgrade its protection of monarch wintering habitat in Mexico.

Recent NRDC Milestones in the Fight to Save Monarchs

We mobilized more than 113,000 of our members and activists to sign a petition demanding Dow AgroSciences remove Enlist Duo from the market. Not only that, we generated an outcry against Enlist Duo in Congress that included signatures from 32 lawmakers calling on the EPA to take a closer look at the devastating health and environmental impacts of this herbicide.

On the global arena, we ramped up international pressure, including 50,000 petitions from NRDC members and activists, on the UNESCO World Heritage Committee to declare the Monarch Butterfly Biosphere Reserve in Mexico in danger due to the destruction of monarch habitat in the United States and Canada by glyphosate. In response, UNESCO launched a formal evaluation of the request.

NRDC and Monarch Watch Planting Milkweed

Monarch Watch is a nonprofit educational outreach program based at the University of Kansas that focuses on the monarch butterfly, its habitat, and its spectacular fall migration. NRDC partners with Monarch Watch to plant milkweed at schools, churches, and garden clubs to help save North American monarch butterflies.

Since 2016, Monarch Watch has been distributing milkweed plants, featured in this Monarchs for Moms campaign, for planting on tribal lands and other locations along the monarchs’ migration route.

NRDC in Action

NRDC joins with Monarch Watch to distribute free milkweed plants to schools across the country and turn students into butterfly gardeners.

Bill Heban, USFWSmidwest/Flickr
onEarth Story

Projects across the Midwest are trying to bring milkweed and nectar-filled flowers back to the landscape.

Southwest Dispatch

Situated along the monarch’s migration corridor, the Sooner State is coming up with creative ways to save the imperiled pollinators.

Sam Droege/USGS Bee Inventory and Monitoring Lab
onEarth Story

Beekeepers are busy as, well, bees, devising new ways to keep pollinators healthy (and ensure you get your almonds)

Midwest Dispatch

This conservation law has been saving our flora and fauna since the 1970s. The Trump administration should stop fiddling with it.

Personal Action

Be a good neighbor to struggling pollinators by turning your backyard into a welcome pit stop.

bark
onEarth Story

New research shows a certain type of milkweed can harm monarchs—but we still need to give these butterflies something to snack on.

Explainer

You may have never heard of them, but there are hundreds around the world. Find out what makes this specific type of reserve so special.

TexasEagle
onEarth Story

Common insecticides are killing monarch butterfly larvae, says a USDA study.

onEarth Story

Rufa red knots rely on Delaware’s horseshoe crab–covered beaches, but climate change and development threaten both species’ survival.

onEarth Story

The Moth Migration Project gathers ink-and-paper insects from all over the world in an immersive crowd-sourced installation.

Mike Mozart
onEarth Story

A new report says the most widely used weed killer probably causes cancer.

onEarth Story

Rising CO2 levels could upset the delicate relationship between the butterflies and their parasites.

onEarth Story

Plus, Trump’s wildfire hot air and the job-killing effects of fuel efficiency rollbacks.

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