In the tiny seaside village of Pacific Grove. CaliforniaThere is no escaping the monarch butterfly.
Butterfly murals abound here: one scatters across the wall of the hotel, another decorates the school. As for local businesses, there's the Monarch Pub, the Butterfly Grove Inn, and even Monarch Knitting (a local yarn store). Every fall, the small town hosts a butterfly parade where local elementary school children dress up in butterfly costumes. The city's municipal code even makes it illegal to “molest or interfere with the monarchs in any manner” with a possible fine of $1,000.
After all, Pacific Grove is better known by another self-imposed nickname: “Butterfly City, USA.”
But Butterfly Town, like the rest of California, has a problem. The species behind this pump are disappearing at an alarming rate amid rampant pesticide use, habitat loss, extreme weather and the climate crisis. The stakes are dire; Monarch numbers in the western United States have plummeted over 99% since 1980s.
If nothing changes, experts fear Western monarchs almost 100% chance of extinction by 2080.
“It’s important to recognize that Butterfly City is a living thing that needs our help, not just orange and black merchandise,” said Natalie Johnston, education manager at the Pacific Grove Museum of Natural History, who also directs the museum’s monarch programs.
Pacific Grove has long been the official “overwintering” site for monarch butterflies, which flock from the Pacific Northwest to the California coast. every late fall and winter on their annual migration route. In past years, tens of thousands The monarchs took refuge in the city's designated Monarch Sanctuary, gathering around tree branches in huge clumps and bursting into giant orange clouds.
In one week in December 2022, volunteers counted nearly 16,000 butterflies sheltering at Pacific Grove Sanctuary. But this year, in the same December week, the number of butterflies was 107.
For many biologists, monarchs serve as a canary in the coal mine for future environmental impacts, especially on other pollinators.
“These are some of the most studied butterflies,” said Emma Pelton, senior biologist at the nonprofit Xerces Invertebrate Conservation Society. “So the more we know about them and the more we understand all the threats that they face, it's a direct correlation to the threats that these other butterflies and other insects face.”
Although the U.S. Fish and Wildlife Service has proposed that all monarch species, including populations in the east and west, be officially listed as endangered under the Endangered Species Act, the Department of the Interior delay in decision making on this list.
However, all hope is not lost for the Butterfly City. The Natural History Museum's Johnston and a group of other staff and volunteers are fighting for their namesake invertebrates, diligently tracking their numbers and calling for their protection.
On a recent clear December morning, Johnston and four volunteer “citizen scientists” gathered outside the city's small monarch shrine, bundled in hats and gloves for their weekly butterfly count. Across the state, researchers rely on citizen scientists to collect data in real time, helping them get a true picture of where the monarch population is located.
One of the butterfly counters and history museum assistant professor, Kat Morgan, described herself as a “data freak.” Part of the appeal of counting butterflies, she says, is the ability to contextualize current numbers within broader patterns and trends.
“My job is to help people fall in love with butterflies or fall deeper in love so they take action,” she said.
Equipped with binoculars, clipboard and carrying small green laser pointers (to help count), a group of volunteers headed into the roughly three-acre forest preserve.
Inside the sanctuary, butterflies hung from the branches of eucalyptus trees in the shadows like a darkened chandelier, occasionally bursting into the sunlight in sudden bursts of color. The volunteers were mostly silent, looking up, squinting through binoculars. In the distance the Pacific Ocean roared dully.
When monarchs gather in large groups, volunteers can count them by assessing the overall density of butterflies and how many of them typically are in one group. region. But when they're more scattered, like this December morning, volunteers count every flattened pair of wings they see.
The presence of monarchs here from year to year is somewhat mysterious; Because the lifespan of migrating monarchs is only nine months or less, each wave of butterflies arriving in Pacific Grove has never been there before. Scientists still don't understand howMore precisely, they know which tiny piece of land and specific tree to fly to, hundreds of miles south of where they began their journey.
At the top of one of the eucalyptus trees, a group of volunteers spotted a sizable pile of monarch chicks. One person counted 27 butterflies, another counted 28. Johnston checked the number of butterflies on her clipboard.
“If we do have 28, that would be our highest total for the year,” she said.
After another count, another volunteer agreed with the higher number: “28!”
“Hooray!” Johnston greeted them, encouraging them.
The final volunteer count for the morning was 226 butterflies: a far cry from the huge totals of previous years, but better than every other week of the 2025 season in Pacific Grove. According to volunteers, one can only guess why this particular weekly count could be different. Numbers fluctuate, and there may always be butterflies that volunteers don't notice.
On a larger scale, the reasons for the decline in monarch numbers over the past 50 years are more obvious.
Since the 1980s, Pelton said, rampant coastal development across the state has likely contributed to some of the big downturns. Even the Pacific Grove Preserve today, she noted, is “a green space among a sea of houses.”
“The same thing is happening with many of these major wintering grounds,” she said. “We lose sites every year. We continue to lose sites, and we continue to lack meaningful legal protection for the vast majority of them.”
The climate crisis is also responsible for some of the decline. This winter may be second or third largest account recorded western monarchs, the Xerces Society reported in early December, due in part to warmer summers and drought. through the west.
“Climate change may now be the straw that breaks the camel’s back,” Pelton said. “But there are other root causes that, fortunately, we are likely to be able to address more easily in the near future than climate change, such as reducing pesticide use.”
Pesticides have been a particularly pressing problem in Pacific Grove. At the beginning of 2024, Butterfly City was the center of the monarch. “mass mortality event” after hundreds of butterflies were exposed to pesticides and died.
Johnston and other volunteers still remember stumbling upon the dying butterflies. on private property near the sanctuary grounds: I saw them convulsing for days on end, huddled together on the ground. Some volunteers still cannot look at photographs and videos of those days or read about any scientific discoveries. Watching the effects of pesticides in real time – “convulsions, convulsions” – was terrifying, Johnston said.
According to a new study conducted this year, a total of 15 different pesticides were found in butterflies. County officials and study authors, including Pelton, were unable to pinpoint a specific source but determined the toxins may have resulted from unreported or untraceable residential or commercial use in Pacific Grove. Beyond the pesticides used in large-scale farming operations, simply using household products for household purposes can pose a huge threat to monarchs—and homeowners. no need to report their use.
For many, the entire saga of 2024 turned into an investigation into an unsolved murder.
“There were bodies,” Pelton said, “but no weapons, no criminal.”
However, the mass die-off has sparked a broader conversation in Pacific Grove about pesticides, including seemingly harmless pesticides labeled “organic” that homeowners may not realize are harmful to monarchs as they fly through town before landing at the sanctuary. Johnston began knocking on neighbors' doors and handing out pamphlets on how to maintain their properties in a butterfly-conscious manner, such as planting native plants that bloom and avoiding pesticides.
“Monarch butterflies depend on you!” – the brochures implored.
Luckily, for now, Butterfly City is still full of monarch enthusiasts. People are willing to assign their own personal meaning to butterflies, Johnston said. Visitors to the sanctuary often tell her they love the species because of its strength (they weigh less than a paper clip but can fly more than 100 miles a day) or because of its transformation from a humble caterpillar to a winged beauty.
Whatever the reason, butterflies are a big deal in Pacific Grove.
“They are harmless and beautiful,” Johnston said. “There’s something about monarch butterflies that seems to resonate with everyone.”
