U.S. Butterfly Populations Decline by 22% Over Two Decades

A comprehensive study reveals alarming trends in butterfly numbers, driven by habitat loss, climate change, and insecticide use.

A new study analyzing 12.6 million butterfly sightings shows a 22% decline in butterfly populations across the continental U.S. from 2000 to 2020.
Researchers found that 33% of studied species experienced significant declines, with 22 species losing over 90% of their populations.
Key drivers of the decline include habitat loss, changes in insecticide use, and the impacts of climate change, particularly in the Southwest.
The Pacific Northwest was the only region with a slight population increase, primarily due to a temporary boom in the California tortoiseshell species.
Experts emphasize the need for conservation efforts, including planting native wildflowers, reducing pesticide use, and supporting policies to protect butterfly habitats.