The U.S. Fish and Wildlife Service announced that it will review whether the monarch butterfly should be included on the endangered species list.
The agency said habitat loss had resulted in substantial declines in the insect's population.
In a notice published Wednesday in the Federal Register, the agency said it will conduct a "status review" at the request of the nonprofit groups the Center for Biological Diversity, the Center for Food Safety and the Xerces Society for Invertebrate Conservation. There will be a 60-day window for the public to comment on the proposal.
The colorful insects are found throughout North America, and some populations migrate thousands of miles across multiple generations each year.