Village News, a publication of the community of Cabin John, MD. For many of us, perhaps the first butterfly we were able to identify was the Monarch. They were our companions of summer with their bright orange and black wings floating over flower-strewn gardens, as if this Earth was indeed their dominion. In recent summers, though, the children of Cabin John and much of the eastern U.S. would have been lucky to see more than a handful. The Monarch (Danaus plexippus), once one of the most abundant butterflies of North America, has suffered a tremendous population crash over the past twenty years. On their wintering grounds in the highland conifer forests in the state of Michoacan, Mexico, as recently as 1996 they once numbered as high as 1 billion individuals. Since then they have plummeted to only 33 million counted in 2013. That may still seem like a lot of butterflies. But to put in perspective, imagine if the human population had declined by 92% over the same period!
Monarchs are known for their impressive migration. Photo by Tarnya Hall, used under Creative Commons licensing.For decades, ecologists north of Mexico pointed fingers at Mexican officials as responsible for the precipitous decline in monarch populations. They turned a blind eye, we said, to illegal clearing of the oyamel fir forests where the monarchs cluster in winter in great numbers and where poor villagers eked out a leaving through timber harvesting or rustling. But now, with these areas better protected, Mexicans have a right to point the finger back at the gringos. At a conference last February in Washington, DC, I was lauding ex-President Salinas for his country’s unparalleled biodiversity and the steps they had taken to protect it. Then I brought up the monarchs. Before I could say more he replied, “But it is American farming practices that are to blame for reducing the number of Monarchs.” And he is right. Conservationists, Mexican and American, attribute the disappearance of mikweed host plants to new agricultural practices in the Midwest—and along the Monarch’s main route to and from Mexico—where genetically modified seeds are bred to resist herbicides that eliminate milkweed nearby. Once established, the farmers can spray Roundup with abandon and kill any wild milkweed that lives between the regimented crop rows. Increased use of these genetically modified crop strains and herbicides in fields of the two most planted crops, corn and soy beans, are correlated with the steep decline in Monarch populations between 1999 and 2010. The leading expert on monarch populations, Dr. Chip Taylor, estimates the loss at 120-150 million acres of the monarch’s milkweed habitat across much of the cornbelt in the Midwest. The solution is to restore milkweed on a grand scale, to provide stepping stones, or way stations of “milkweed habitat” where returning generations can stop and breed as they make their way back north to us. There are several groups working nationally to spearhead this noble effort. What can we in our little hamlet of Cabin John do to restore monarchs to their rightful place? The first step is to be honest with ourselves. It’s not fair to blame just corn and soy bean farmers in the Midwest—we are a nation of Roundup users. So the first step is to stop using this dangerous chemical and other pesticides (including herbicides and insecticides) that kill a wide range of plants and beneficial insects and endanger our own health. (Pulling weeds is a chore; we have had great success with mixing a gallon of vinegar with a pinch of salt and a few drops of dishwashing detergent. If you drip the mixture on the offending weed’s root area it will be dead in a few hours, especially on sunny days. Try it!).