Iconic Butterfly Has Declined by 80 Percent in Recent Decades
WASHINGTON— The Committee on the Status of Endangered Wildlife in Canada released a report today recommending that the monarch butterfly be protected as an endangered species due to population decline and ongoing threats to the butterfly’s epic migration. Previously, in Canada, the monarch was classified as a species of special concern; now the minister of the Environment and the Canadian Endangered Species Conservation Council have nine months to decide whether to add the butterfly to the endangered species list.
Monarch populations have plummeted by 80 percent since the mid-1990s because of milkweed loss in their summer breeding grounds and ongoing threats to the Mexican forests where the orange-and-black butterflies overwinter. Under Canadian law endangered status is defined as facing imminent extirpation or extinction.
“The 80 percent decline in the monarch population points to extinction if we don’t act fast,” said George Kimbrell, a Center for Food Safety senior attorney. “Protecting monarch butterflies under the Endangered Species Act is essential to their survival, and will provide a road map for safeguarding their habitat and ensuring their recovery.”
In the United States, the U.S. Fish and Wildlife Service is legally bound to decide by 2019 whether the monarch should be listed as a threatened species, following a 2014 petition and a 2016 lawsuit from the Center for Biological Diversity, Center for Food Safety and allies championing the protection of the butterflies.
“It’s still hard to believe that an animal once as common as the monarch could be in such big trouble, but we are now at real risk of losing this magnificent butterfly,” said Tierra Curry, a senior scientist at the Center for Biological Diversity. “The U.S. Fish and Wildlife Service should follow Canada’s lead and protect the monarch under the Endangered Species Act before it’s too late.”
A recent study by the U.S. Geological Survey concluded that there is a substantial probability that eastern monarch butterfly populations could decline to such low levels that they face extinction. Researchers estimate the probability that the monarch migration could collapse within the next 20 years is between 11 percent and 57 percent.
Monarch butterfly migration is now recognized as a “threatened process” by the International Union for the Conservation of Nature. The eastern migratory population of monarchs is now recognized by the natural heritage organization NatureServe as “critically imperiled.” In Mexico monarchs are classified as a species “subject to special protection.”
In the United States, the butterflies’ decline has been attributed to increasing use of Monsanto’s Roundup herbicide, a potent killer of milkweed, which is the monarch caterpillar’s only food source. The dramatic surge in Roundup use and “Roundup Ready” crops has virtually wiped out milkweed plants in midwestern corn and soybean fields. It is estimated that in the past 20 years these once-common butterflies may have lost more than 165 million acres of habitat — an area about the size of Texas — including nearly one-third of their summer breeding grounds.
In addition to loss of summer milkweed, monarchs are also threatened during the fall migration by multiple factors including habitat fragmentation, drought and insecticides. Their overwintering grounds in Mexico are threatened by logging, mining, climate change and increasing acreage of avocado farms.