More monarch butterflies have flown into SLO County. Here’s how many are in Pismo Beach
Western monarch butterflies continue to migrate into San Luis Obispo County to stay the winter in groves of trees before venturing out to breed in the spring and summer.
Thousands of the orange-and-black winged insects now weigh down the branches of the eucalyptus trees in the Pismo State Beach monarch butterfly grove along Highway 1, according to California State Parks.
About 10,431 were counted at the grove Nov. 17 — up from 8,114 counted on Nov. 2, according to State Parks interpreter Danielle Bronson.
Bronson suspects more butterflies may flutter into the grove over the next few weeks. The butterflies fly into the grove to overwinter, meaning they stay put to save energy during the winter months before dispersing to breed.
During the weeks surrounding the Thanksgiving holiday, the Xerces Society for Invertebrate Conservation organizes an annual count of monarch butterflies in overwintering groves throughout California.
The Thanksgiving count, conducted mostly by volunteers, helps scientists keep tabs on the population size of the important pollinator, which is considered to be teetering on the edge of extinction.
Around the state, roughly 50,000 overwintering monarch butterflies have been counted, according to Emma Pelton, a senior conservation biologist with the Xerces Society.
However, that number only represents about a third of the data from all of the overwintering sites across the state — so it’s likely more monarch butterflies will be counted before the count ends Dec. 3, Pelton said.
“This is definitely not our best year,” Pelton said. “But it’s not the worst.”
The roughly 10,000 counted at the Pismo Beach grove is much lower than the 24,000 counted in the grove last year, according to the Xerces Society.
But this year’s numbers so far are still higher than the devastatingly low counts in 2018, 2019 and 2020, when fewer than 7,000 were counted.
That’s a trend that appears to be echoed across the other overwintering sites in San Luis Obispo County, according to Jessica Griffiths, a wildlife biologist with the Center for Environmental Management of Military Lands and volunteer coordinator for the Xerces Society’s Thanksgiving count.
Griffiths said she’s working with more than 30 volunteers to count the monarch butterflies at 57 sites in San Luis Obispo County.
Many of the volunteers were able to conduct counts before the Nov. 18 storm hit and will likely do a second count before the Xerces Society’s count ends on Dec. 3, Griffiths said.
“We’re definitely seeing numbers lower than last year, but higher than those scary-low years,” she said. “But I’m expecting the numbers to go up a bit when we count the sites for a second time after the holiday.”
Pelton said she’s excited to see a few new overwintering sites being identified in California this year.
These are sites that perhaps historically volunteers hadn’t had access to for counting monarchs or have only recently been discovered to be hosting overwintering butterflies, she added.
The Pismo Beach grove typically has one of the highest counts of overwintering butterflies compared to other groves in California.
Other sites popular among the overwintering butterflies include the Jack and Laura Dangermond Preserve in Santa Barbara County, Pacific Grove Monarch Butterfly Sanctuary in Monterey County, Hazard Cove in Montaña de Oro State Park, the Morro Bay Golf Course and Fiscalini Ranch Preserve.
