A combination of climate change, pesticide use, habitat loss — land is converted for agriculture or development — could be responsible for their declining populations, the New York Times reports.
What they did: Researchers analyzed 12.6 million individual butterflies across 35 monitoring programs from 2000 to 2020.
State of play: The study found that 102 of the 140 butterfly species found in the San Antonio area are decreasing nationally.
22 species are increasing in population, and 16 have had little change.
Threat level: The U.S. has lost 22% of its butterflies in the last 20 years.
"The loss that we're seeing over such a short time is really alarming. Unless we change things, we're in for trouble," Elise Zipkin, a quantitative ecologist and one of the study's authors, told the New York Times.
