WASHINGTON, July 5, 2016 - The U.S. Fish and Wildlife Service agreed Tuesday to render a decision by June 30, 2019, on whether or not to protect the monarch butterfly under the Endangered Species Act (ESA).

Claiming that milkweed – the only food source for monarch caterpillars – is being destroyed by farmers who use Monsanto’s Roundup herbicide on their crops, the Center for Biological Diversity and Center for Food Safety filed a petition in August 2014, for federal protection. After an initial review of the petition, the Fish and Wildlife Service concluded four months later that protection under the Endangered Species Act “may be warranted.”

In March, the two non-profit groups filed a lawsuit to compel the government agency to render a decision and on Tuesday it agreed, according to a settlement filed with the U.S. District Court for the District of Columbia. Under the agreement, the agency must propose protection for the monarch, deny protection or assign it to the “candidate” waiting list for protection by the end of June 2019.

The groups assert that the monarch population has declined by 80 percent in the past two decades. “An 80 percent decline points to extinction if we don’t act fast,” George Kimbrell, a senior attorney for the Center for Food Safety said in a statement. “Protecting monarch butterflies under the Endangered Species Act is essential to their survival, and will provide a roadmap for safeguarding their habitat and ensuring their recovery.”

Monsanto agrees that the disappearance of milkweed plants has hurt the monarch population, as have severe winters and drought caused by climate change. But the company, on its website, also stressed that farmers need herbicides to protect their crops. To ameliorate the situation, Monsanto said it is working with groups like the National Fish and Wildlife Foundation, the Iowa Monarch Conservation Consortium and Pheasants Forever to create special new habitats for the butterfly.

Weed management has been a factor in the decline of milkweed habitat,” Monsanto said. “However, those of us in agriculture can be part of the solution to restoring it.”

The Center for Biological Diversity and Center for Food Safety argue that Monsanto’s herbicide and farmers are the main problems, and the only solution is ESA protection for the monarch.

The two groups say that use of Roundup herbicide over the past 20 years has “virtually wiped out milkweed plants in Midwestern corn and soybean fields” and the butterflies have lost more than 165 million acres of habitat.

“The monarch’s future is bleaker today than ever before,” said Tierra Curry, a senior scientist at the Center for Biological Diversity. “Endangered Species Act protection can’t come soon enough for this beautiful but beleaguered butterfly.”