The precipitous decline of species around the world continues to make headlines. One million species worldwide are at risk of extinction; North America has lost three billion birds in the past 50 years, and 30 percent of known invertebrate species are poised to vanish.
One of those insects slated for evanescence is the ochre-winged, enigmatic, magnificent monarch butterfly that has so captured the imagination of Americans. This iconic pollinator species has the most highly-evolved migration pattern of any known butterfly or moth. Weighing in at less than a gram, monarchs migrate thousands of miles on a slow and sailing wing.
Western monarchs, which overwinter on the coast of California from Mendocino to Northern Baja, (eastern populations overwinter in central Mexico), have suffered a catastrophic decline in recent years. Volunteer community scientists collect data on these butterflies annually – an effort that began in 1980 – in what is known as the “Western Monarch Thanksgiving Count.” This long-term dataset reveals a harrowing record of decline: 99 percent in the western U.S. over the past four decades.
In the fall of 2020, volunteers recorded 1,914 butterflies overwintering on California’s coast, where millions of butterflies used to drape coastal boughs in a fluttering orange blanket. The monarch’s decline was startlingly apparent at Pismo State Beach Monarch Grove, located just north of Los Angeles: 6,700 monarchs were sighted here in 2019; last fall, just 200.
Scientists continue to deliberate the causes of monarch decline. Butterfly disappearance is commonly attributed to the use of insecticides on the monarch’s host plant, milkweed. In light of recent population collapses, however, other anthropogenic pressures may be in play. California’s record-breaking wildfires burned extensive tracts of monarch habitat and emitted historic quantities of carbon dioxide into the atmosphere. Researchers stipulate that this atmospheric pollution may induce milkweed plants to ramp up the production of toxic steroids in their tissues. Known as cardenolides, these toxins provide the monarch with its signature chemical defense against predators, but higher toxin concentrations may actually reduce the butterfly’s ability to fight off a deadly parasite, Ophryocystis elektroscirrha.
Just after monarch population data were released last December, the U.S. Fish and Wildlife Service decided, dismissively, that it would not recommend protection for the monarch butterfly. The agency cited “higher-priority listing actions” as reasoning to delay consideration for the monarch butterfly until 2024. To add insult to injury, courts recently ruled that monarchs weren’t protected under the California Endangered Species Act, a law that the state alleged doesn’t apply to insects. State and federal officials continue to waffle, but the monarch butterfly likely won’t be able to wait much longer.
The western monarch’s near-collapse has warranted concern from other areas of government. Rep. Salud Carbajal (D-Calif.), whose district encompasses Pismo State Beach Monarch Grove, said he and other public officials were trying to “yell at the top of our lungs,” describing the butterfly’s situation as nothing less than a crisis. Carabajal, alongside a group of fellow representatives and senators, has worked to introduce the Monarch Action, Recovery, and Conservation of Habitat Act (MONARCH Act). The bill would appropriate funds for on-the-ground conservation projects to resuscitate western monarch butterfly populations. Where federal agencies have failed, Congress has a responsibility to intervene.
This legislation comes among a list of pro-biodiversity legislation introduced in the 117th Congress, from the “30 by 30” resolution to the National Biodiversity Strategy. The work doesn’t stop there, though, as the globe witnesses an insect apocalypse and our nation seriously risks losing one of its most quintessentially American insects in its entirety.
Plant milkweed in your garden and ask your elected officials to act. Importantly, come mid-May, monarchs will begin to arrive in Colorado. Do pause to take a long gaze when one of those ethereal, tawny lepidopterans sails past.
Soleil Gaylord is a junior at Dartmouth College studying government and environmental studies. She is from Telluride.
