With Labor Day just ahead, people on both coasts and across the Great Plains should be celebrating the start of one of North America’s great migrations. The spectacle of monarch butterflies working their way back to their overwintering sites, across hundreds or thousands of miles, is the longest known insect migration on Earth.
It’s such a popular event, and the monarchs are so beautiful—their brilliant orange wings bordered with a black-polka-dot hem—that seven states have named monarch butterflies their state insect.
The monarchs have been decimated—populations are down 90 percent from their 20-year average. That’s “a loss so staggering,” said Tierra Curry, a senior scientist at the Center for Biological Diversity, “that in human-population terms it would be like losing every living person in
the United States except those in Florida and Ohio.”
As it happens, that’s putting it conservatively. From its peak of a billion individuals in the mid-1990s, the monarch butterfly population is down to an estimated 35 million now, a 97 percent decline.
Last winter’s population count at the butterfly’s overwintering site in Mexico was the lowest ever recorded. That’s what pushed the Center for Biological Diversity, the Center for Food Safety, the Xerces Society, and the renowned butterfly biologist Lincoln Brower to file their joint petition this week, according to Curry. That number—35 million—may sound like plenty of butterflies to opponents of the Endangered Species Act. But the fatal tendency in the past, said Curry, has been to withhold protected status for butterflies until they are on the brink of extinction. When FWS listed the Miami blue butterfly as an endangered species in 2012, for instance, the population was down to fewer than 50 individuals.
Sarina Jepsen, endangered species director at the Xerces Society, noted that this is the 100th anniversary of the death of the passenger pigeon Martha, the last of another species once considered too numerous to become extinct. “History demonstrates that we cannot afford to be complacent about saving the monarch,” she said.
The listing petition blames the decimation of monarch butterflies largely on the practices of a single American corporation, Monsanto, which bills itself “a sustainable agriculture company.” Its introduction of genetically modified herbicide-tolerant soybeans in 1996 and corn in 1998 resulted in a 20-fold increase in use of its Roundup weed killer by American farmers, according to the petition. As a result, the milkweed on which monarch butterflies depend vanished from a vast area in the Midwest. The weed killer, together with other developments, has since destroyed 167 million acres of monarch butterfly habitat (an area the size of Texas), according to the petition.
For Monsanto, which is accustomed to being called “the most hated company in America,” this may not be quite as bad as being caught dressing up in Wehrmacht uniforms and killing puppies. But its role in the demise of the monarchs could yet become a public relations nightmare. Earlier this year, Monsanto suggested on its blog that the blame lies more with loss of wintering habitat in Mexico. But the company also said it’s “eager to join efforts to help rebuild monarch habitat” and “to increase milkweed populations on the agricultural landscape.” So far, according to those close to the issue, that has meant attending meetings but without offering specific action or financial investment.
In an interview, Brower noted that Monsanto can afford to make a difference. (It reported $4.25 billion in third-quarter sales, and surging profits on weed killers.) The quickest way to get results, he suggested, would be to plant milkweed on highway margins and power-line rights of way, and to create no-weed-killer buffer zones on the margins of agricultural fields.
“We don’t see farmers as the problem,” said Tierra Curry. “We see farmers as part of the solution.” The Conservation Reserve Program, under which the government pays farmers to leave some land fallow, could become a means for rebuilding milkweed stands, she said, though Congress has recently been cutting back on the amount of eligible acreage. She also suggested reducing or eliminating ethanol subsidies, which have vastly increased the amount of land devoted to corn, and instead subsidizing farmers to plant milkweed.
Individuals concerned about the catastrophic decline in monarch butterflies can help by planting milkweed, she said. But it should be a milkweed species suitable to your area. (Here’s a list of suppliers.) It might also help to write a letter to Monsanto CEO Hugh Grant at the company’s headquarters—800 N. Lindbergh Blvd., St. Louis, MO 63141—and to sign a public petition asking the FWS to protect monarch butterflies.
That agency has three months to decide if there’s evidence for a reasonable person to believe monarch butterflies are in danger of extinction. If it agrees, it then has a year to research the issue. But the process typically drags on for three years and sometimes more than 10.
By then, at the current rate, there may not be any monarch butterflies left to protect.