Monarch Butterflies

Iconic Status Can Obscure Science and Philosophy

No wonder we admire Monarchs. Their unique migration from Mexico to Canada (and back) rightly inspires our awe. But Monarchs also serve as icons for the “environmentally worried elite” who rarely think through all the scientific, historical, and philosophical implications of their concerns. They especially seem oblivious to the many ironies that accompany contemporary concern for Monarchs.

In the 2015 film, “Butterfly Town, USA,” ecologist Lincoln Brower cited a number of factors that he perceived as threatening Monarchs: GMO agriculture and its related herbicides, global warming, and habitat loss — including illegal logging in Mexico pertaining to one of the Monarchs’ overwintering homes. If people are illegally logging in Mexico, in some ways they’re merely mimicking the habitat destruction in California that began during the 1850s. New herbicides may indeed have dire consequences for the Monarchs’ milkweed plant, but probably only within the farming fields themselves (over a million acres of California savanna remain free from agricultural interference). And sadly, all sorts of unrelated problems hitchhike on the environmental bogeyman of our times, global warming. Establishing actual causation between various environmental changes and climate change is actually far more difficult than media stories would have us believe.

When 19th century loggers stripped millions of acres of eastern woodlands in the United States, the Monarch population exploded, since open lands (including meadows and savannas) favor these butterflies as much as forests repulse them. During the 20th century, landowners and government forestry agencies began fostering a limited return of eastern forests, but that geography still favors Monarchs now far more than it did before all that logging. Yet those concerned about Monarchs never mention this.

A monarch butterfly on a milkweed plant in Michigan (photo from WikiCommons).

Also during the 19th century, farmers in California began converting the Central Valley and other locations into agricultural land that now produces around a fourth of America’s food supply. Unfortunately, some of this acreage once hosted the milkweed habitat that Monarchs so highly favor. But, at the same time, Californians were also introducing the eucalyptus from Australia — and Monarchs are strongly attracted to this tree, often gathering on their branches by the thousands during the overwintering season. Beginning in the 1960s, some Californians began opposing the eucalyptus with the usual objections about non-native species. The city of Santa Cruz even proposed eradicating them, but lost a 2015 court case to eucalyptus defenders.

A dual row of eucalyptus trees transplanted in California, ca. 1900. Photo from the California Historical Society, via WikiCommons.

Monarch butterflies are an iconic species, and thus receive a disproportionate amount of human attention and concern. Organizations like the World Wildlife Fund or WildEarth Guardians use poster child species to appeal to humans for their causes, and thus we see pandas, elephants, tigers, or other iconic species in their advertisements — but poster child campaigns tend to bypass more complex scientific facts or the philosophical values that people sometimes confuse with science. We see all of this reflected in debates over the Monarch and eucalyptus habitats in California.

Alarm over an apparent recent drop in western Monarch populations is similar to alarmism regarding coral reefs. Monarch populations and coral reef health have highly incomplete assessments during very short historical periods of data gathering. In other words, we have not been paying attention to these topics long enough to appreciate any “natural” cycles that may exist. What was the situation of the oceans’ coral reefs in any era before the advent of underwater technology? No one knows. How have the Monarch populations in California fluctuated since the 1850s? No one knows. Monarch populations may oscillate wildly for reasons we do not yet understand, and possibly due to factors unrelated in whole or part to human activities. But if we experience the coming insect apocalypse that some entomologists fear (sometimes primarily blaming climate change), should we expect Monarchs to be exempt from the general die-off?

In the meantime, among all of earth’s species, humanity has a unique role and responsibility as environmental stewards, and our stewardship does not take place in an environmental paradise where human activity is, ipso facto, defiling. We need as much science as possible to inform our stewardship, but we also need to distinguish between the general realms of scientific facts and philosophical values, lest the quality of both suffer. This worldview extends far beyond considerations for a single iconic species.

Copyright © 2026 Will Sarvis. All rights reserved.

REFERENCES

Anon., “Wildlife Dilemma: Kill Birds to Save Fish? Cormorants Near the Mouth of the Columbia are Threatening Fish Runs,” Associated Press (Aug. 2, 2014).

Achva Benzinberg Stein and Jacqueline Claire Moxley, “In Defense of the Nonnative: The Case of the Eucalyptus,” Landscape Journal 11:1 (Spring 1992), pages 35–50.

Matthew Daly and Jeff Barnard, “U.S. Moves Ahead with Plan to Shoot Spotted Owl’s Rival,” Associated Press (Feb. 29, 2012).

Christopher Joyce, “Saving One Species at the Expense of Another,” NPR’s Morning Edition (July 11, 2013).

Bjørn Lomborg, The Skeptical Environmentalist (Cambridge University Pr., 2001), page 330 (coining the phrase, “environmentally worried elite”).

Stephen B. Malcolm and Myron P. Zalucki, eds., Biology and Conservation of the Monarch Butterfly (Natural History Museum of Los Angeles County, 1993) — especially see John Lane, “Overwintering Monarch Butterflies in California: Past and Present,” pages 335–44; Richard I. Vane-Wright, “The Columbus Hypothesis: An Explanation for the Dramatic 19th Century Range Expansion of the Monarch Butterfly,” pages 179–87.

Emma Marris, “The Great Eucalyptus Debate,” The Atlantic (Nov. 30, 2016).

Save Our Big Trees v. City of Santa Cruz, et al, Court of Appeal, Sixth District, California (filed Oct. 23, 2015), 241 Cal.App.4th 694.

Alana Wise, “Insect Populations Drop Even Without Direct Human Interference, a New Study Finds,” NPR’s All Things Considered (Sept. 12, 2025).