U.S. Geological Survey scientists and a graduate student at the Missouri Cooperative Fish and Wildlife Research Unit at the University of Missouri partnered with the Missouri Department of Conservation to conduct a literature review of the direct effects of grassland management practices and pesticide exposure on monarchs in North America. This story is featured in WMI's Outdoors News Bulletin.
U.S. Geological Survey scientists and a graduate student at the Missouri Cooperative Fish and Wildlife Research Unit at the University of Missouri partnered with the Missouri Department of Conservation to conduct a literature review of the direct effects of grassland management practices and pesticide exposure on monarchs in North America. Their findings reveal knowledge gaps in understanding direct effects of grassland management activities such as mowing, burning, grazing, and haying on monarch butterfly survival, reproduction, and development.
Monarch butterfly declines mirror a broader trend of insect losses globally. Insects provide essential ecosystem services—including pollination, pest control, and nutrient cycling—and form the base of many food webs. In economic terms, insect pollination services in the U.S. alone were valued at \$34 billion in 2021, and global animal pollination service estimates were between \$235-\$577 billion. Yet roughly 20% of North American pollinator species are at risk of extinction, and butterfly abundance in the U.S. dropped 22% between 2000 and 2020.