Butterflies are disappearing at a ‘catastrophic’ rate

In a sobering revelation, a comprehensive new study has found that butterfly populations across the United States have declined by 22% since 2000, a trend scientists are calling “catastrophic.”

Published on March 6, 2025, in the journal Science, this first-of-its-kind nationwide analysis highlights the alarming loss of these delicate pollinators, attributing the decline to a deadly combination of insecticides, climate change, and habitat loss.

The study, which analyzed 12.6 million butterfly sightings from 76,957 surveys across 35 monitoring programs, paints a grim picture.

According to AP News, butterfly numbers in the Lower 48 states have been dropping at an average rate of 1.3% per year since the turn of the century. Of the 650 butterfly species in the U.S., 114 showed significant declines, while only nine increased.

Notably, 96 species were too scarce to even register in the data, and 212 others lacked sufficient numbers to track trends.

Collin Edwards, the study’s lead author and an ecologist at the Washington Department of Fish and Wildlife, told NPR that this widespread decline across species and regions suggests “really big processes” at work, including habitat destruction, pesticide use, and climate shifts.

The Washington Post emphasized the scale of the collapse, noting that the total butterfly population in the contiguous U.S. shrank by over a fifth in just two decades.

Specific species have been hit hard: the red admiral, known for its calm demeanor, is down 44%, while the American lady butterfly has plummeted by 58%.

Even the invasive white cabbage butterfly, a resilient species, has seen a 50% drop, according to AP News.

The Southwest—encompassing Arizona, New Mexico, Texas, and Oklahoma—experienced the steepest decline, with butterfly numbers falling by more than half, a trend Edwards linked to the region’s intensifying heat and drought.

Butterflies are more than just a symbol of beauty; they play a critical role in ecosystems. As AP News reported, they are vital pollinators, particularly for crops like Texas cotton, though less prominent than bees.

Their decline signals broader trouble for insect populations, which David Wagner, a University of Connecticut entomologist not involved in the study, described as “the tree of life being denuded at unprecedented rates.”

While seemingly modest, Wagner told AP News that a 1.3% annual decline compounds into a “catastrophic and saddening” loss—potentially halving butterfly populations continent-wide in 30 to 40 years.

The Washington Post echoed this sentiment, quoting Wagner as calling butterflies a “yardstick” for measuring insect health broadly.

The ripple effects could destabilize ecosystems and threaten human food systems, a concern amplified by Cornell University butterfly expert Anurag Agrawal.

In an email to AP News, Agrawal warned that the loss of butterflies—and by extension, other insects—is “undoubtedly a bad sign for us, the ecosystems we need, and the nature we enjoy.”

Scientists point to three primary drivers behind this crisis.

NPR highlighted large-scale habitat loss from agriculture and development, which has shrunk the spaces butterflies need to thrive.

Pesticides, especially in the Midwest, are directly harming many species, while climate change is pushing butterflies out of their comfort zones.

Edwards noted in NPR that southern populations are faring worse than northern ones, likely due to rising temperatures and drier conditions.

The Washington Post added that some species, like the Acadian hairstreak, may be retreating north as the climate warms, a shift observed by Jeffrey Glassberg of the North American Butterfly Association.

Nick Haddad, a co-author of the study and Michigan State University entomologist, told AP News that these factors often work in tandem, creating a “perfect storm” for butterflies.

His personal observations of the endangered St. Francis Satyr butterfly—now down to just two sightings at a North Carolina bomb range—underscore the fragility of even specialized species.