Written by Ceci Kimball | June 2026
Monarchs are one of the most recognizable butterfly species in North America, and it isn’t difficult to understand the fascination. The common name for the monarch derives from American entomologist Samuel Hubbard Scudder who coined the designation in 1874, given the species is a larger butterfly and “rules a vast domain,” stretching across the North American continent.1 However, monarchs have also risen in notoriety because of their recent, and substantial, decline. Since the 1990s, populations of eastern monarchs beginning their migratory journey in Mexico have declined by 80%, and in California the western monarch population has fallen by 95% since the 1980s. 2
Monarchs are an indicator species, meaning their decline serves as an ecological warning sign for environmental degradation. As monarchs disappear, other essential pollinators like bees and hummingbirds, face the risk of decreasing as well. Monarch caterpillars feed exclusively on milkweed plants while journeying nearly 3,000 miles from Mexico to Canada, but with rising pesticide usage, deforestation, and growing land development, the already impressive journey becomes more difficult. Experts often cite habitat and biodiversity loss as the primary reasons for the species’ near-extinction: without native plants to support the butterfly, the population will decline.
Yet, there is a glimmer of hope for the bright orange and black pollinator. This year’s overwintering data from Mexico, provided by the World Wildlife Fund, shows a 64% increase in the population of eastern monarchs compared to last year. The butterflies utilized 7.24 acres of forested habitat during their semi-hibernating state of diapause this year, a sharp rise from the previous 4.42 acres utilized in the winter of 2024-25. This season of monarch migration appears promising, considering the decrease in forest degradation within butterfly’s critical winter habitat, with recorded forest loss primarily attributed to illegal logging (4.58 acres), forest fires (1.43 acres) and drought (0.28 acres). 3
In December of 2024 the United States Fish and Wildlife Service formally proposed to designate the monarch as a “threatened” species under the Endangered Species Act. After a months-long review period, the decision was delayed and is not expected to be finalized within the fiscal year, however, is in the decision-making pipeline for future action. 4
Monarch butterfly sipping the nectar of a milkweed plant | U.S. Fish & Wildlife Service
Ways You Can Help:
Organized community efforts are vital for saving species with plummeting populations. Efforts range from assisting in habitat restoration to providing local monitoring data to tracking species season to season.
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- Plant native milkweed (Grow Milkweed Plant’s Milkweed Map)
- Access regional milkweed guides and find the best nectar sources for your local ecosystem
- Register your yard or garden as a Monarch Way Station
- Join community science campaigns to track the presence of monarchs throughout their seasonal life cycles
- Find opportunities with conservation organizations:
- Participate in state/regional efforts:
If you’re interested in local action, Nature At The Confluence hosts prairie monitoring every Tuesday at 4:00 pm over the summer to record the presence of monarchs. Data is shared through the Monarch Larva Monitoring Project.
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1. Cambridge Entomological Club. Psyche. no. 3, Cambridge Entomological Club, 1874, p. 10, https://www.biodiversitylibrary.org/page/12551620.
2. Xerces Society. “Monarchs In Decline.” Xerces Society, xerces.org/monarchs/conservation-efforts. https://xerces.org/monarchs/conservation-efforts#:~:text=Now%2C%20researchers%20and%20citizen%20scientists,the%201980s%20in%20coastal%20California.
3. Rendón-Salinas, E., et al. “Area of Forest Occupied by the Colonies of Monarch Butterflies in Mexico, During the Overwintering Period 2025-2026.” https://www.worldwildlife.org/publications/area-of-forest-occupied-by-the-colonies-of-monarch-butterflies-in-mexico-during-the-overwintering-period-2025-2026/.
4. Monarch Watch. “Monarch Listing Decision.” Monarch Watch, https://monarchwatch.org/listing/.
