"It was devastating to arrive at the sanctuary and see so many butterflies on the ground, many still alive but convulsing and unable to fly."
Natalie Johnston said that after finding roughly 200 monarchs dead or dying on a private lawn about 20 meters from the boundary of Monarch Grove Sanctuary in late January 2024. Johnston runs interpretive programs at the Pacific Grove Museum of Natural History, and she was the one who bagged the specimens and sent them to a US Geological Survey lab in Sacramento. The lab results, published in July 2025 in the journal Environmental Toxicology and Chemistry, found an average of seven different pesticides in every butterfly tested, drawn from a pool of fifteen compounds across the samples. Concentrations of one pyrethroid, cypermethrin, ran as high as 2,645 nanograms per gram of dry tissue, a level the study's authors and the Xerces Society both describe as lethal to insects.
Here is the part that should stop any longtime resident: Pacific Grove has had a law against harming its monarchs since 1952. The fine is $1,000. It has never applied to what actually killed those 200 butterflies.
A Law Built for a Different Century's Threat
City ordinance 11.48.010 makes it unlawful to "molest or interfere with" the butterflies during their stay within city limits, a rule dating to a 1952 city ordinance and still enforced today by the Pacific Grove Police Department. It is the law every docent mentions, the one printed on interpretive signs, the one that gives the town its nickname real civic teeth. It was written to stop people from picking butterflies up, chasing them, or disturbing their clusters. Physical interference, in other words.
The 2024 die-off had nothing to do with a tourist's hands. The dead monarchs were found on a private property adjacent to the sanctuary, and a review by Monterey County could not identify who applied the chemicals or when. What the tissue analysis could confirm is that the butterflies absorbed a mix of insecticides, herbicides, and fungicides at concentrations high enough to cause the convulsions Johnston described. No ordinance written to stop hand-molestation reaches a lawn treatment two properties away. The sanctuary's oldest protection and its newest documented threat simply do not overlap.
The Number Residents Are Actually Watching This Year
Every October, Pacific Grove residents know the butterflies are coming back. What changed is what that return now measures. The Xerces Society's Western Monarch Count released its results for the 2025-26 overwintering season on January 29, 2026: approximately 12,260 monarchs across 249 surveyed sites, the third-lowest tally since the count began in 1997. The two years below it were 2024, at 9,119, and 2020, at 1,901, the all-time low. For comparison, western monarchs regularly numbered in the low millions through the 1980s.
| Season | Monarchs counted | Context |
|---|---|---|
| 1980s (typical) | Low millions | Population considered stable |
| 2020 | 1,901 | All-time recorded low |
| 2024 | 9,119 | Second-lowest on record |
| 2025-26 | 12,260 | Third-lowest on record |
At the Pacific Grove sanctuary specifically, one weekly count last November came to 99 butterflies for the entire two-acre grove, a handful of loners scattered through the canopy and a single cluster of 72. That same reporting noted 2021 as a year when one tree alone held thousands. The gap between those two pictures, one tree with thousands versus a whole grove with 99, is the story residents are living through this season, not an abstraction from a press release.
The Federal Protection That Keeps Slipping
Given numbers like these, a federal Endangered Species Act listing has seemed close for two years. The US Fish and Wildlife Service proposed listing the monarch as threatened on December 12, 2024, with a companion 4(d) rule and a critical habitat designation that named the Pacific Grove sanctuary as one of the protected units. Statute gave the agency until roughly December 2025 to finalize that rule.
It did not happen. In its Fall 2025 Unified Agenda, the Department of the Interior moved the monarch listing into a category called "long-term action," meaning the agency does not expect to act within the next twelve months. Xerces called the delay disappointing and said a final listing was now unlikely before fall 2026 at the earliest. In February 2026, the Center for Biological Diversity and Center for Food Safety sued the Fish and Wildlife Service to force a binding decision date, and as of this writing no final rule has been issued.
So the town's 1952 ordinance is not a backstop while residents wait for federal protection to arrive. For now, it is the only protection in place, and it was never built to cover the mechanism that killed 200 butterflies two winters ago.
How to Time a Visit This Season
None of this makes the sanctuary less worth visiting. It makes the visit more worth understanding. A few things that change what you'll actually see:
- Monarchs typically begin arriving in mid-October and stay through February, with the population usually peaking the week after Thanksgiving.
- Below 55°F, monarchs cluster and stay still to conserve energy. Visit before 11 a.m. on a cool or overcast morning if you want to see clustering, which looks like small pinecones or dead leaves bunched in the branches.
- Above 55°F on a sunny afternoon, the same butterflies take flight, and the grove turns into a slow procession of orange against the eucalyptus and Monterey pine.
- Docents from the Pacific Grove Museum of Natural History are typically on site from 11 a.m. to 3 p.m., and they know which trees the monarchs have chosen that particular day, since clusters shift from one visit to the next.
- Each fall, the museum runs a two-part docent training, a virtual lecture on monarch biology followed by an in-person orientation at the sanctuary, for anyone who wants to spend the season learning the grove rather than just visiting it. Contact the Pacific Grove Museum of Natural History directly for this year's schedule.
What the Sanctuary Actually Tests
The monarch count is sometimes described as a nature story, and it is, but it also functions as an annual referendum on how well a small city can protect something it has legally claimed to protect for 74 years. The 1952 ordinance answered the question the town faced when it was written: can Pacific Grove stop people from touching the butterflies? It still can, and the fine still stands. The question the 2024 die-off raised is different, and the ordinance was never asked to answer it. Whether a $1,000 fine and a strongly worded municipal code can do anything about a lawn treatment applied on a Tuesday afternoon two lots over is not a question this town has solved yet, and neither has the federal government, which keeps moving its own deadline further out.
That is the thing to watch for when the first monarchs settle into the pines this month. Not just whether they come back, but whether the number holds anywhere close to last year's, and whether the town's oldest protection ever gets updated for the threat its own museum staff already documented in a peer-reviewed journal.
If you are weighing a move to Pacific Grove and want a local's read on more than the butterfly count, from what a property near the sanctuary boundary actually requires of an owner to how the town's older housing stock interacts with its conservation rules, Carmel Coast Realty can walk you through it. Schedule a local consultation whenever you're ready to talk specifics.
