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Monarchs returned in higher numbers for Thanksgiving count, but were then battered by winter storms.

For immediate release January 31, 2023


Emma Pelton, Senior Endangered Species Conservation Biologist and Western Monarch Lead, the Xerces Society; 503-212-0706; [email protected]

Isis Howard, Endangered Species Conservation Biologist, Western Monarch Community Science, the Xerces Society; 503-212-0546; [email protected]


Portland, Ore.; Tuesday, January 31, 2023---In the weeks before heavy rains battered the California coast, volunteers grabbed their binoculars and headed out in an annual pilgrimage for a beloved animal. This year, their efforts for the 26th Western Monarch Count paid off with good news: a final tally of 335,479 butterflies during the study’s Thanksgiving counting period.

“We can all celebrate this tally,” says Emma Pelton, a conservation biologist at the Xerces Society and western monarch lead. “A second year in a row of relatively good numbers gives us hope that there is still time to act to save the western migration. That said, we know we still have a long way to go to reach population recovery, and the storms that hit right afterwards mean we’ll start the spring with far, far less than this total.”

The results are a welcome reprieve from a total of less than 2,000 individuals counted in 2020 and nearly 250,000 in 2021. Yet the butterflies remain far from the low millions seen in the 1980s, and their recovery remains vulnerable to pressures like habitat loss, pesticide use and climate change.

Central Coast hosts majority of western monarchs

More than 250 people participated in this year’s Western Monarch Count, surveying a total of 272 sites across coastal California and a few sites in interior California and Arizona between November 12 and December 4, 2022. Volunteers count clusters of monarchs as they huddle together to overwinter in groves of trees, often non-native eucalyptus.

California’s Central Coast continued to host a majority of the largest sites and overwintering western monarchs, with over 130,000 butterflies reported in both Santa Barbara and San Luis Obispo counties. The Bay Area witnessed a comeback from low numbers last year, with more than 8,000 butterflies reported in surrounding counties such as Alameda, Marin and Solano. 

The largest count was 34,180 butterflies at an overwintering site in Santa Barbara County owned by The Nature Conservancy, followed by 25,710 butterflies at a private residential site in Santa Barbara County. Pismo State Beach Monarch Butterfly Grove had the third largest monarch count and is open for public viewing, with 24,128 butterflies reported at their peak. 

Small population is vulnerable to extreme weather

Shortly after the Thanksgiving count period ended, back-to-back atmospheric rivers drenched most of the California coast, battering overwintering sites. Observers reported flooding, downed tree limbs and even entire trees uprooted. While some sites fared well, volunteers at others reported more monarchs on the ground, blown from their clusters and vulnerable to the cold, wet conditions and predation.

“Small populations are particularly vulnerable to being snuffed out by extreme weather, so we are lucky these storms occurred in a relatively good year,” said Pelton. “We don’t want to count on luck alone to ensure the survival of the western monarch migration.”

That calls for not only restoring more monarch butterfly habitat throughout their range, but doubling down on making sure overwintering sites are protected and resilient to climate change. Site managers and landowners can take steps to replace dead and dying trees, landscape sites to prevent or mitigate flooding, and plant native nectar sources.

Monarch butterflies still lack legal protections

“Unfortunately, there continues to be very little meaningful protection for the species or its habitat. Overwintering sites in particular continue to be destroyed and damaged each year," says Isis Howard, a conservation biologist with The Xerces Society and coordinator of the count.  

While migratory monarch butterflies were declared endangered on the IUCN Red List of Threatened SpeciesTM last summer, they are not yet listed under U.S. or state Endangered Species Acts, which would afford the species legal protections. A federal listing by the U.S. Fish and Wildlife Service is anticipated in fiscal year 2024.

“The plain fact is that if we lose overwintering sites in California, we could lose migratory western monarchs. Development, eucalyptus removal, and tree trimming all need to be managed thoughtfully if we are to leave space for these animals to survive," says Howard.

How you can help

Once western monarchs depart from their overwintering sites, they rely on finding high-quality habitat and safe breeding grounds across several western states. Everyday gardeners, park managers, schools, and others can make simple but meaningful changes to help the western monarch population recover:

  1. Plant native milkweed.
  2. Plant a diversity of nectar plants, ideally native to your area. 
  3. Stop using pesticides, or minimize risk associated with pesticide use.
  4. Call on legislators to support policies such as Recovering America’s Wildlife Act and the Monarch Action, Recovery, and Conservation of Habitat Act.
  5. Contribute to community science projects that track monarchs, such as the Western Monarch Milkweed Mapper, Western Monarch Mystery Challenge, and nationwide Integrated Monarch Monitoring Program.

The Xerces Society has been active in monarch and pollinator conservation in California for decades. Xerces' work helps restore monarch overwintering sites, expand pollinator habitat on farms, and has distributed more than 130,000 pollinator plants through Xerces’ Habitat Kit Program.



About the Western Monarch Count

The Western Monarch Count is a volunteer-powered community science effort run by the Xerces Society and count co-founder, Mia Monroe. It runs for a three-week period around the Thanksgiving holiday, and is designed to collect data on the status of the migratory western monarch population by using a standard protocol to estimate the number of butterflies clustered at overwintering sites. A second count period occurs around the New Year’s holiday and lasts for two weeks, which estimates the monarchs’ seasonal decline over winter.


This effort is powered by more than 250 dedicated volunteers who collect data at overwintering sites. The Xerces Society also thanks our western monarch conservation funders who make this work possible: Bureau of Land Management, California Department of Fish and Wildlife, California State Parks Foundation, California Wildlife Conservation Board,, Forest Service International Programs, The Marion R. Weber Family Fund, Monarch Joint Venture, National Fish and Wildlife Foundation, Natural Resources Conservation Service, San Diego Zoo Wildlife Alliance, The Taggart Saxon Schubert Fund, US Fish and Wildlife Service, and Xerces Society members.


The following images are released for media use.

To download, right-click on image and select "save."


Description: Total monarchs reported and number of overwintering sites monitored for the Western Monarch Thanksgiving Count from 1997 to 2022.

Image credit: Xerces Society

File name: Xerces_WMC_Thanksgiving_1.27.2023


Description: Monarch butterflies cluster together in treetops for protection over winter, pictured here at Pacific Grove, California.

Photo credit: Isis Howard, Xerces Society

File name: MonarchCluster_11.5.22_c.IsisHoward.XercesSociety


Description: Christina Garcia, a naturalist with East Bay Regional Park District and regional coordinator for the Western Monarch Count, leads a monarch viewing tour at Ardenwood Historic Farm last November. Downed limbs became a common sight at monarch overwintering grounds following intense rainfall from mid-December into January.

Photo credit: Isis Howard, Xerces Society

File name: ChristinaGarciaEBRPD_Ardenwood_c.IsisHoward.XercesSociety


Description: Map depicting migratory routes of both western and eastern monarch butterfly populations.

Image credit: Xerces Society

File name: XercesSociety_MonarchMigrationMap_27jan2023