Monarch butterfly added to endangered species list

The monarch butterfly, an unmistakable sign of spring, is now considered an endangered species at risk of extinction.

The International Union for Conservation added the monarch butterfly to its Red List Thursday, officially classifying it as endangered due to climate change and threats to its habitat.

The group says its native population – which is known for its migrations from Mexico and California in the winter to summer breeding grounds throughout the rest of North America – has shrunk as much as 72% over the past decade.

Logging activity and deforestation were blamed for destroying the butterfly's habitat, while use of pesticides and herbicides in agriculture have killed both the butterflies and milkweed, the plant that larvae of the monarch butterfly feed on. Climate change has sped up the species' demise by fueling wildfires and severe weather, and worsening droughts like the one California is currently mired in.

The IUCN says the Monarch butterfly's western population is at greatest risk of extinction. It's population has shrunk from as many as 10 million to 1,914 butterflies between the 1980s and 2021, the group said, and there's remains concern as to whether enough of the species remains to maintain its population and prevent extinction.

Southern Californians, however, can do something to help local monarch butterflies thrive despite the challenges.

"Part of the biggest problems we have here in Southern California is people were planting the wrong kind of milkweed," Horticulturist Sarah Smith at Roger's Gardens in Corona del Mar. She said much of the milkweed being used in Southern California landscaping was using a tropical species of milkweed with bright red or yellow flowers.

"This one has a light-colored flower so that's how you know that's the right one, but more importantly, it dies back in winter time," she said, holding a pot of Monarch butterfly-preferred milkweed.