Despite concern over the monarch butterfly’s population decline, the U.S. Department of the Interior has delayed—indefinitely—the decision to list the species as threatened under the Endangered Species Act (“ESA”). The listing was expected to be finalized in mid-December 2025, following a proposal issued by the U.S. Department of Fish and Wildlife in December 2024. Instead, the Department of the Interior placed the decision on its Spring 2025 Agency Rule List as a “long-term action”—a designation that carries no deadline and effectively places the decision on hold for an undetermined period of time. The change not only delays action on the monarch butterfly but also signals broader slowdowns for many other species awaiting listing decisions.
The U.S. Fish and Wildlife Service’s December 2024 Special Status Assessment Report identified habitat loss and degradation as primary drivers of the monarch’s health decline. Chief among these threats are the conversion of grasslands to agricultural uses, the widespread application of herbicides and insecticides, continued urban development, and the compounding effects of climate change. The report concluded that these largely human-driven stressors have contributed to the ongoing loss and degradation of breeding, migratory, and overwintering habitat throughout the monarch’s North American range
If finalized, the proposed listing of the monarch butterfly as threatened under the ESA would authorize the U.S. Fish and Wildlife Service to adopt species-specific protections tailored to preventing further population decline and designate approximately 4,395 acres of critical habitat. The U.S. Department of the Interior’s decision to classify the listing as a “long-term action,” however, signals that these protections are not expected to move forward in the near term.