What America’s monarch butterflies need to thrive

Compared to just a couple of decades ago, only a tiny fraction remains of the monarch butterflies that migrate across the United States every year.

If these iconic pollinators are to avoid extinction — if we’re to preserve the sight of their magnificent annual migrations for future generations — one thing is clear: We’ll need to preserve their food.

Monarch caterpillars rely on one plant, milkweed, for their food. But pesticide use has devastated milkweed across the country. We need to boost native milkweed numbers to save the monarchs, starting by getting state governors to direct the planting of milkweed on public lands.

A dire situation

In late July this year, the International Union for Conservation of Nature listed North America’s monarch butterfly as endangered.

This decision is a reflection of the dangers facing the monarchs today.

A variety of factors is driving their shrinking numbers: a decrease in the forested habitats where adults hibernate for the winter, disruptions to migration and reproduction from climate change, and — clearest of all — the disappearance of milkweed, the food monarch caterpillars need to survive.

As these dangers have compounded, monarch numbers have dropped precipitously. Between the 1980s and 2021, the numbers of the western monarch butterflies that migrate between the Pacific Coast and various states in the West dropped by more than 95%. Meanwhile, their eastern brethren also have suffered through a steep drop in their numbers — approximately 80%.

Despite this stark decline, the U.S. government has not taken action. In 2020, wildlife officials noted that monarchs were threatened with extinction. Yet the Fish and Wildlife Service still declined to offer them protections under the Endangered Species Act.

Without the government’s protection, the monarchs need our help. And there’s one clear and simple thing we can do to ensure these beautiful pollinators keep brightening our skies for decades to come: Give them more food. Our state decision-makers should take action to plant more milkweed on public lands, so our country’s struggling monarch butterflies have a better chance at survival.

We know this strategy works

Think of how much unused space we see every day. Highway medians, small green spaces interspersed between buildings, small plots of trees — they’re all around us.

We can make better use of unused public space and offer a helping hand to a struggling iconic species at the same time.

We’ve raised this call before over the past few years, and we’ve begun to see monarch numbers beginning to stabilize in some areas.

But whether that’s a statistical anomaly or truly good news, we don’t yet know. Either way, there’s more work to be done. We need to do more to offer our help to these majestic pollinators before it’s too late.