If you’re a butterfly gardener, there’s no doubt you already know about the plight of the Monarch butterfly (Danaus plexippus). The last few years have seen a precipitous decline in the numbers of the major migratory population, with scientists estimating a drop of a whopping 90% in the last 20 years. In a recent press release, Tierra Curry of the Center for Biological Diversity tried to put that statistic into perspective, saying, “The 90 percent drop in the monarch’s population is a loss so staggering that in human-population terms it would be like losing every living person in the United States except those in Florida and Ohio.”
Scientists agree that the biggest threat to these butterflies is loss of habitat. As most folks know by now, Monarchs require milkweed for their caterpillars. While native to most areas of the U.S. and Canada, milkweed is considered a weed to commercial farmers and ranchers. In recent years, herbicide-resistant forms of crops like corn and soybean have been bred and planted extensively, allowing farmers to spray their fields indiscriminately with Roundup, killing milkweed (and other weeds and wildflowers) and leaving huge areas in the middle of the country devoid of the one plant monarchs really need. (Learn more here, including why milkweed in Texas is especially important.)
It’s not all bad news, though. Sometimes it takes something really major to get the public’s attention, and this information could be it. A group of scientists and organizations is now pushing to have the Monarch listed as “Threatened” under the Endangered Species Act, which would provide special protection to this butterfly and its habitat. In Mexico, the government has moved to protect the winter roosting sites. Closer to home, local butterfly gardeners are doing all they can to help, adding milkweed to home and public gardens and spreading the word along the way.
On a recent trip to the Sleeping Bear Sand Dunes National Park in western Michigan, I was thrilled to see large stands of Common Milkweed (Asclepias syriaca) everywhere. Even better was the sight of dozens of monarchs flying around the area. By late August, this generation is the one that will soon begin its migration to Mexico. They’ll need all the help they can get to make their 2,000 mile journey, so if you live in the eastern half of the U.S., now’s the time to fill your butterfly garden with late-blooming flowers to sustain them along the way.
Have you spotted monarch butterflies or caterpillars on your milkweed this year? Drop by our Community forums and share your sightings to help Birds & Blooms track where the monarchs were in 2014.