SACRAMENTO, Calif. – The monarch butterfly will not be listed as “threatened” under the Endangered Species Act for at least a few more years, the federal government announced Tuesday December 15, even though its populations have plummeted.
The U.S. Fish and Wildlife Service said the monarch meets the criteria for listing, but limited resources mean other species will be listed first. Preliminary data from the annual Thanksgiving count of monarchs that overwinter on the California coast showed only 2,000 to 3,000 individuals. Dr. Arthur Shapiro, a professor of evolution and ecology at the University of California at Davis, said that number should be orders of magnitude higher.
“The entire California population has not exceeded 30,000 for the last two winters,” he said, “and it looks like this year will be even worse. They should be more like 20 million or 30 million.”
The reasons for the decline of this iconic orange-and-black butterfly still are being studied, but the culprits include losing habitat to development, pesticides, and climate change. In addition, proliferation of parasite-prone non-native milkweeds in coastal areas may be leading the butterflies to breed early in the winter instead of the spring.
Dr. Cheryl Schultz, a biology professor at Washington State University at Vancouver, was part of a team predicting three years ago that if the monarch population dropped below 30,000, the species could spiral past the extinction threshold – the point at which there are too few individuals to keep it going. However, Schultz said she remains hopeful the species can be saved.
“With people working together and using the science,” she said, “I think there’s incredible promise, and resiliency of the monarch populations, to turn them around.”
For now, the monarch will remain a “candidate species” to be listed in the future as threatened. The Endangered Species Coalition is asking butterfly enthusiasts to take a stand and call for protections for the monarch and other pollinators.