Mass Die-Off of Western Monarch Butterflies Linked to Pesticides, Study Finds

Mass Die-Off of Western Monarch Butterflies Linked to Pesticides, Study Finds

A new peer-reviewed study has linked pesticides as a likely cause to a mass die-off of Western monarch butterflies that occurred in 2024. In January 2024, researchers found hundreds of dead or dying monarch butterflies near the Pacific Grove Monarch Sanctuary in California, where Western monarch butterflies typically overwinter. As The Guardian reported, researchers found the butterflies showing signs of neurotoxic pesticide poisoning, leading t…

Lab Tests Point to Culprit in Monarch Butterfly Die-Off

Hundreds of monarch butterflies mysteriously died in southern California last year, and new research points to a likely culprit lurking in the landscape: common pesticides. Scientists say these peer-reviewed findings published in Environmental Toxicology and Chemistry offer rare, direct evidence linking chemical exposure to the monarchs' dramatic decline, reports the...

Monarch butterflies’ mass die-off in 2024 caused by pesticide exposure – study

The Guardian reported A 2024 mass monarch butterfly die-off in California was probably caused by pesticide exposure, new peer-reviewed research finds, adding difficult-to-obtain evidence to the theory that pesticides are partly behind dramatic declines in monarchs’ numbers in recent decades. Researchers discovered hundreds of butterflies that had died or were dying in January 2024 near an overwintering site, where insects spend winter months. Th…