Monarch Butterflies Could Go Extinct If We Don't Take These 3 Steps, Experts Say

Monarch butterfly, endangered 0:42

(CNN) --

One of the most popular and recognizable insects is in danger of extinction, according to a global organization focused on conservation and sustainability.

It is the monarch butterflies.

The International Union for Conservation of Nature (IUCN) has added the migratory monarch butterfly to its Red List of Threatened Species under the category "endangered", the group said in a statement on Thursday.

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"It's hard to see monarch butterflies and their extraordinary migration teetering on the brink of collapse, but there are signs of hope," said Anna Walker, species survival officer for invertebrate pollinators at the New Mexico BioPark Society, who works in partnership with the IUCN Species Survival Commission.

The monarch is the only butterfly known to make a two-way migration like birds, according to the US Forest Service.

Every winter, monarchs living in the eastern part of North America migrate to the Sierra Madre mountains in Mexico, and those from the west migrate to coastal regions of California, according to the federal agency.

Those migrations have been a bystander event in the past.

The IUCN Red List shows what actions need to be taken to save nature from extinction and is an often-cited resource in peer-reviewed scientific research, according to its website.

The listing is not related to the US Endangered Species Act, and currently the US Fish and Wildlife Service has not listed the monarch butterfly as an endangered species.

CNN has reached out to the Fish and Wildlife Service.

The IUCN estimates that the native population of Monarch butterflies has declined by between 22% and 72% over the last decade, and the western population has declined by 99.9% between the 1980s and 2021, putting it in higher risk of extinction.

Habitat loss and the climate crisis

Monarch butterfly population increased in Mexico 0:59

Habitat destruction and rising temperatures brought on by the climate crisis are increasingly threatening the species, the IUCN said.

When they are caterpillars, monarchs feed exclusively on milkweed leaves, according to the National Wildlife Federation.

But droughts have limited milkweed growth and rising temperatures have prompted earlier migrations, the IUCN said.

There has also been an increase in the use of the herbicide glyphosate—particularly on corn and soybean crops—which has caused a severe decline in milkweed in the US.

Scientists had hoped that the monarch could withstand the human-induced climate crisis, given its exceptionally wide geographic range, but the species has been found to rely heavily on environmental cues for critical life cycle events, according to the World Wildlife Fund.

The reproduction, migration and hibernation of the butterfly are intertwined with seasonal changes, which global warming is disrupting.

hope for butterflies

But it's not too late to protect monarch butterflies, experts say.

"Fortunately, there is still time to act," conservationist Scott Hoffman Black told CNN.

Black is executive director of the Xerces Society for Invertebrate Conservation, a science-based conservation organization that "protects the natural world through the conservation of invertebrates and their habitats," according to its website.

"They (scientists) recommend promoting milkweed growth, maintaining dense forests and reducing pesticide use in the monarch's range," the World Wildlife Fund said.

And monarch butterflies have popular allure on their side.

“We are encouraged by the thousands of people who have taken it upon themselves to help monarchs by planting milkweed and nectar flowers and protecting these animals from pesticides,” Black said.

Wendy Caldwell, who has been working with monarchs since around 2007, told CNN that she quickly learned the power of this beloved insect to captivate people and bring them outdoors and into conservation.

Caldwell is the executive director of the Monarch Joint Venture, a nonprofit organization that coordinates a network of more than 110 organizations across the United States to conserve migrating monarchs, according to its website.

"I think this IUCN listing will continue to help us add to that momentum by simply raising awareness that monarchs are in trouble," he said.

"They need our help, and everyone has a role to play."

endangered animals Monarch Butterflies