They’re considered by many to be one of the most iconic, recognizable insects in North America. Now, monarch butterflies are officially endangered.

The International Union for the Conservation of Nature added the migrating monarch butterfly to its “red list” of threatened species. They’re now categorized as “endangered.” That’s just two steps away from “extinct in the wild.”

Stuart Pimm, an ecologist at Duke University, said, “It’s a devastating decline. This is one of the most recognizable butterflies in the world.”

IUCN estimated the population of monarch butterflies in North America declined somewhere between 22% and 72% over the last decade, depending on the measurement method.

In North America, millions of monarch butterflies embark on the longest migration of any insect species known to science.

Migrating monarchs winter in the mountains of central Mexico, then head north thousands of miles to southern Canada, breeding multiple generations along the way. Loss of habitat, the increased use of herbicides and pesticides, and climate change are all factors into the decline of the migrating monarch.

Nonmigratory monarch butterflies in Central and South America were not designated as endangered. Also, the United States hasn’t listed monarch butterflies under the Endangered Species Act, but several environmental groups are lobbying for the addition.

Conservation groups are also working to protect the monarchs’ overwintering sites. To help the monarch butterfly population rebound, plant some milkweed. Monarchs love it.

The Associated Press contributed to this report.