A monarch butterfly in a garden in Santa Cruz.
(Courtesy Alasdair Drysdale)

Monarch population continues to plummet, but feds still opt to delay endangered species protection

The number of monarchs observed on the West Coast has plummeted from millions in the 1980s to fewer than 10,000 this year. Only 500 butterflies were observed in Natural Bridges during this year’s Thanksgiving count.

Early numbers from the volunteer-led Western Monarch Thanksgiving count this year estimate the Western migratory population of monarch butterflies to be at an all-time low: possibly fewer than 10,000.

Despite this dramatic decline, federal officials decided Tuesday that the monarch will not be considered for endangered species protection until possibly as late as 2024.

“They need help right now,” said Emma Pelton, a senior conservation biologist at the Xerces Society. Xerces runs the monarch count, which monitors about 200 locations where monarchs spend the winter, spanning the West coast from Ensenada to Mendocino. The delay in protections, she told Lookout, could mean any help from endangered species designation would arrive “potentially much too late.”

Monarch butterflies face a multitude of human-induced threats, including habitat loss, insecticides, wildfires, and climate change, which affects their habitats and migration patterns.

Only 550 butterflies were counted at the eucalyptus grove at Natural Bridges State Beach here in Santa Cruz over Thanksgiving weekend — and this was the highest number found at any single site in the country.

It’s a big drop from the 2,000 counted at Natural Bridges in last year’s count, and merely a rounding error compared to the numbers consistently observed at the site in the 1980s: 120,000-plus, according to numbers shared by the park on social media.

Based on Xerces Society estimates, there were millions of butterflies in the 1980s. In the 1990s, the population “really started to tank,” Pelton said. But from the late ‘90s into the 2000s, the population was relatively stable, in the hundreds of thousands of butterflies. As recently as 2017, they counted around 200,000 butterflies.

“Then 2018 happened and we had 27,000 butterflies. Everybody freaked out because it was a single year drop of an order of magnitude,” said Pelton. This year, they are seeing yet another order of magnitude reduction. “In two years we’ve seen about a 99% drop,” Pelton said.

Despite these staggering numbers, the U.S. Fish and Wildlife Service announced Tuesday that, after concluding a comprehensive four-year assessment, it will not be listing the monarch as an endangered or threatened species — at least not this year.

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Fish and Wildlife Service officials said they found the monarch does warrant being added to the list of threatened and endangered species, but doing so is “precluded by work on higher-priority [species].”

“We conducted an intensive, thorough review using a rigorous, transparent science-based process and found that the monarch meets listing criteria under the Endangered Species Act,” U.S. Fish and Wildlife Service Director Aurelia Skipwith said in a statement. “However, before we can propose listing, we must focus resources on our higher-priority listing actions.”

This decision will be reviewed annually, and emergency action could possibly speed up the process. But according to reports by the Associated Press, federal officials don’t plan to propose listing the species until 2024.

“[We’re] really heartened that the service agrees that monarchs warrant protection,” Pelton said, “but to not have a final listing decision, not have them say threatened or endangered really does not help Western monarchs.”

The designation could have designated sites where monarchs wait out the cold season, (called “overwintering sites”), like Natural Bridges, “critical habitat” eligible for federal protection. This is one of the most important things that could be done to slow the decline of the species, according to the Xerces Society.

“We continue to lose sites every year, because of development, and tree cutting, and ongoing drought, and climate change exacerbated factors,” Peloton said.