The population of monarch butterflies is at an "all-time low."
The populations in Vermont have dropped by 90 percent, VPR reported. In Minnesota, monarch larvae have been found on only about five percent of the state's milkweed, according to the Star Tribune.
The rapid decline of these regal butterflies doesn't seem to be a cause for concern for most ecologists.
"If butterflies went extinct tomorrow, we wouldn't notice from an ecological perspective," Karen Oberhauser, a University of Minnesota conservation biologist, told the Star Tribune.
"Citizen science makes a lot of people who might not have a formal ecological education understand what humans are doing to the world," she said. "That makes them want to do something about it."
Oberhauser and her team have been carefully documenting the butterfly's decline, in hopes of calling attention to the problem.
Conservation biologist Kent McFarland a conservation biologist of the Vermont Center for Ecostudies believes there is more than one factor contributing to the monarch's disappearance, VPR reported.
"The weather this year was really the final tipping for them, we think. Last year there was a really horrible drought in the Midwest and Texas where the heart of the monarch population is located. So productivity last year was terrible. We saw very low populations in Mexico overwinter. We expected that." he said.
Monarchs typically migrate from the U.S. to Mexico around October to hibernate, according to monarch-butterfly.com.
McFarland said agricultural practices could also be contributing to the problem, VPR reported.
Milkweed is the monarchs' favorite, and only, food source. The plant declined in population by 58 percent between 1999 and 2010, most likely from pesticide use and a disappearing habitat, the Star Tribune reported.
McFarland has seen a downward trend in monarch populations since 1996. Less than a decade ago the butterflies covered 15 acres of their winter habitat in Mexico, today they cover only three, according to VPR.
"That is a heck of a drop of population," McFarland said.
WATCH:
