1st Natl Analysis: America’s Butterflies Disappearing at ‘Catastrophic’ Rate

The Associated Press

13:09 JST, March 12, 2025

WASHINGTON (AP) — America’s butterflies are disappearing because of insecticides, climate change and habitat loss, with the number of the winged beauties down 22% since 2000, a new study finds.

The first countrywide systematic analysis of butterfly abundance found that the number of butterflies in the Lower 48 states has been falling on average 1.3% a year since the turn of the century, with 114 species showing significant declines and only nine increasing, according to a study in March 6’s journal Science.

“Butterflies have been declining the last 20 years,” said study coauthor Nick Haddad, an entomologist at Michigan State University. “And we don’t see any sign that that’s going to end.”

A team of scientists combined 76,957 surveys from 35 monitoring programs and blended them for an apples-to-apples comparison and ended up counting 12.6 million butterflies over the decades. Last month, an annual survey that looked just at monarch butterflies, which federal officials plan to put on the threatened species list, counted a nearly all-time low of fewer than 10,000, down from 1.2 million in 1997.

Many of the species in decline fell by 40% or more.