Butterflies across the U.S. are disappearing at an alarming rate, according to a new study co-authored by UCLA ecologist Travis Longcore. Published in the journal Science, it reveals that butterfly populations have declined by 22% in just two decades, with over 100 species losing more than half their populations, and 22 species losing more than 90%.
The study is the largest, most in-depth butterfly population assessment ever conducted, analyzing more than 76,000 surveys and 12.6 million butterfly records. Previous research points to habitat loss, pesticide use and climate change as key drivers of these declines.
Butterflies play a vital role in ecosystems as pollinators and as a food source for birds and other wildlife. With 13 times as many butterfly species declining as increasing, scientists stress the urgency of habitat protection and reduced pesticide use to prevent further losses.
The study was conducted by the Status of Butterflies in the U.S. working group, including scientists at Washington State University, Washington Department of Fish and Wildlife and Xerces Society for Invertebrate Conservation.
Read the full study in Science: https://www.science.org/content/article/butterfly-populations-are-plummeting-across-united-states