There hasn’t been an overwhelming amount of good news for monarch butterflies in recent years. Maybe, just maybe, we’re witnessing the early stages of a metamorphosis.
The regal black and and orange insect, a common subject of elementary classroom study, captivates children and adults alike with its remarkable, well-known migration each year between the United States and Mexico.
With a beautiful and still not completely understood precision, these winged navigators travel thousands of miles across North America, with the eastern portion of the species returning each winter largely to the same mountainous areas in Mexico, protected as the Monarch Butterfly Biosphere Reserve. Each journey encompasses several generations of butterflies, with some generations living for only a few weeks.
And while there is something magical about the butterfly’s generational sojourn, the story of the monarch population in recent decades has been anything but a fairytale.
The monarch population has seen a steep decline in the past 20 years, decreasing more than 80 percent. Likely culprits include loss of habitat, pesticide use, pollution and climate change.
The monarch caterpillar depends on milkweed as its host plant and food source, and once the caterpillars transform into butterflies, they need access to nectar plants. The toxins contained in milkweed are harnessed by the monarchs to protect them from predators, but have led to the plant being classified as a “noxious weed” in some areas. That can complicate habitat preservation efforts.
According to the U.S Forest Service, there are more than 100 species of milkweed, but only about a fourth of those species are known to play an important role as host plants for monarchs.
“A lot of it is due to a loss of habitat,” Ba Rae, a conservation specialist for Monarch Watch, said about the monarch population decline in an interview with the BDN. “When they started putting Roundup on fields in the Midwest, the habitat just plummeted, which is a real problem. There was also some logging in the reserves [where they winter in Mexico], which is somewhat of a problem as well.”
The dire population trend reached the point that several organizations petitioned the federal government in 2014 to place monarchs on the endangered species list. The U.S. Fish and Wildlife Service has initially found that federal protection “may be warranted,” but announced in May that its final determination is being delayed until December 2020 in order to gather more scientific information and data.
“Regardless of the decision, we are committed to conserving the monarch butterfly. Monarchs, bees and other pollinators perform a crucial function that sustains ecosystems and put food on our tables,” Wooley said in a May press release.
Despite the ongoing concerns about the monarch population, there may be some good news here in Maine and elsewhere along the monarch’s migration route. A Texas researcher estimated in March that the number of migrating butterflies could be up 144 percent this year.
And a recent story in the BDN outlined the remarkable transformation at a farm in the town of Washington, where the owner estimates there are now thousands of monarchs this year — after only observing a handful in the previous several years that she has owned the property.
The population boost at Slater Farm may be anecdotal, but it’s nevertheless encouraging, and could demonstrate the importance of providing access to milkweed.
“I don’t know if it took several years of not mowing [the large field milkweed at the farm]? I think that probably has helped,” owner Heather Halsey told the BDN.
A year of encouraging estimates and exciting sightings at one Maine farm do not amount to a population rebound, however. After reports of some increased sightings last year, University of Maine at Farmington professor Ron Butler, who also leads the Maine Butterfly Survey, cautioned in an email to the Portland Press Herald last summer that the situation for monarchs “is still very much dire.”
Welcome efforts from conservation groups, researchers and educators already aim to bolster monarch habitat, particularly by promoting and planting native milkweed species.
While many insects are viewed as pests, the monarch butterfly is a bit of an outlier in that it inspires awe when many other species tend to draw ire. Monarchs, and butterflies in general, provide a wonderful, hopeful metaphor for change and adaptation. Ensuring that this insect can continue to inspire — and play its valuable role as a pollinator — will require some action and adaptation from people as well.