Every May and June, Monarch butterflies can be spotted fluttering throughout Kentucky as they take a much needed rest stop along their annual migration south. But biologists are worried that dwindling food supplies and other environmental factors at play in the Bluegrass State could cause problems for the colorful insects in the long run.
Monarch butterflies take a generational migration path north every year – meaning that they reproduce multiple times along their trip – before eventually returning south for the winter. These multiple generations are vital to the journey since the butterflies who originally started the migration are not able to make the entire trip themselves and, if the insects don’t make it south for the winter, they have a hard time surviving cold temperatures.
Courtney Hayes is a wildlife biologist with the Kentucky Department of Fish & Wildlife Resources. She said the commonwealth is a significant stop for the iconic species because they use it as a place to reproduce and store energy, which is becoming harder to do as the adequate habitats and food supply for the butterflies shrinks.
“Flying is very energetically expensive, as you can imagine … they need constant access to food to keep that energy going. So food along the way to wherever they're going is important,” Hayes said. “But the reduction of available food sources has really impacted the species while they're in Kentucky.”
The most important plant for monarch reproduction is milkweed. It is the only plant the species lays their eggs on, and that monarch caterpillars can eat. According to the Xerces Society, a pollinator conservation group, the loss of milkweed plants across the United States is a major factor in the gradual reduction of monarch presence, contributing to a roughly 85% decrease in the population since 1990.
Hayes said milkweed is becoming less prevalent partially because of industrial interferences, as well as more generally a change in people’s preferences.
“A lot of people don't like milkweed. They consider it a noxious weed, but milkweed species are the only plants that monarch butterflies will lay their eggs on, and that their caterpillars can eat. So, it's really important that we provide that for them,” Hayes said.
Chloe Mensch of Murray Monarchs is a conservationist cultivating monarch caterpillars in her Calloway County backyard. In the space, she has planted a combination of milkweed plants for caterpillars to thrive on, which she will then aid throughout their process towards adulthood.
In addition to benefiting the population, Mensch said she uses her garden and knowledge of the species to educate others on the importance of the native plants that monarchs rely on.
“We're just trying to educate people to plant native [and] plant milkweed. You don't have to even do what we do, where we kind of help them out and help them along their way … every little bit counts,” Mensch said.
A lack of food supply is not the only factor impeding on monarch survival.
Mensch, who began monarch-focused planting roughly six years ago, said a changing environment has caused an increase of extreme weather, which has created even more difficulties for the butterflies, noticeably altering their typical migration timeline.
“One year … the monarchs came so early because of the extreme weather on the Gulf … and it was very strange for all of us, especially people that have been doing it longer than me,” Mensch said.
Hayes said the continuation of timeline disruptions in combination with changes in spring blooming could eventually have a drastic effect on the species’ population.
“Sometimes if the blooming and the migration aren't in sync, then the butterflies won't have any food left to eat … or if they're triggered to move up and then it gets … [cold] and the plants die, then the butterflies also die,” Hayes said.
Despite the bleak factors working against the species, Hayes said people can make a significant contribution towards preserving the species by simply planting native in their own backyards, but this includes more than just milkweed.
“A backyard garden is really helpful for monarchs along the way … especially if you live in the city,” said Hayes. “Milkweed is very important because the caterpillars need it, but [but they also need] different blooms throughout the season … so the [adult monarchs] can nectar on any nectaring plant.”
Statewide, the Kentucky Department of Fish & Wildlife Resources, in collaboration with other state departments and stakeholders, has been concerned about the obstacles facing the insects for a decade now, creating the Monarch Conservation Plan in 2016. The initiative focuses on increasing awareness of the problems monarch butterflies face, while also working to increase the presence of optimal habitats to insure the beloved species returns year after year.
