Citing habitat destruction and climate change, the International Union for the Conservation of Nature (IUCN), an organization composed of government agencies and NGOs from around the world, labeled the monarch butterfly as “endangered” and added it to its Red List of Threatened Species this week.
Established in 1964 and based in Geneva, the IUCN is considered one of the most comprehensive sources on the conservation status of animals, plants and fungi.
“The term ‘endangered’ captures people’s attention, but it doesn’t mean what people think it does,” said Ross Winton, an invertebrate biologist for Texas Parks and Wildlife.
Winton recalled the decision in 2020 by U.S. Fish and Wildlife to reject a petition to list monarch butterflies as “threatened” under the Endangered Species Act. The federal agency determined the listing was “warranted but precluded” and moved the migratory butterfly into the queue behind 161 other species. The issue is expected to be revisited in 2024.
The iconic orange-and-black butterflies are widely known for their unique, multi-generation migration that takes them each spring from their overwintering habitat in the mountains of Mexico through Texas to Canada and back.
San Antonio sits in the so-called Texas Funnel, a migratory pathway that sees large numbers of the insects each year.
San Antonio, named the first Monarch Champion City in the country by the National Wildlife Federation in 2015, is home to a fairly stable monarch butterfly population, according to Winton. Texas Parks and Wildlife recently conducted its own statewide monarch butterfly assessment.
“It came back that it’s secure, but that’s using different data sets than IUCN,” Winton said.
Grant Ellis, San Antonio’s Parks and Recreation Departmental liaison for the Mayor’s Monarch Pledge, said the IUCN news was “concerning” and that the city will continue to monitor the monarch’s status.
Monarch Joint Venture, a monarch butterfly conservation organization, clarified in a statement that IUCN designation does not provide any protections or regulatory authority like an Endangered Species Act listing in the U.S. would.
“This is another loud call to action that we need all hands on deck for monarch and pollinator conservation,” said Wendy Caldwell, the organization’s executive director.
The IUCN listing came as a surprise to some local monarch butterfly advocates, who just months ago were cheering the news that the eastern migratory population was up 35% this year over last, while California’s distinct monarch population, which moves up and down the Pacific Coast, had vaulted more than 12,000% in 2021.
“It’s hard to sort it out,” said Cathy Downs, who propagates milkweed, the monarch butterfly’s host plant, in her yard in Comfort in the Texas Hill Country. Downs works as a monarch conservation specialist for Monarch Watch, a citizen science initiative based at the University of Kansas at Lawrence that tracks the monarchs’ migration each fall by tagging the creatures.
“I’m glad they issued the statement and brought monarch conservation back to the forefront,” she said.
When the Endangered Species Act listing was being debated, those who tag monarch butterflies raised concerns that they would no longer be able to participate in the initiative to track the migrating insects via tiny stickers placed strategically on their wings, as the listing would likely prohibit such interactions with a protected species.
But that’s not a worry here, said Chip Taylor, founder of Monarch Watch.
“The IUCN has absolutely no jurisdiction in the United States,” said Taylor. “It’s a wake-up call.”