For centuries, monarch butterflies have migrated from across North America to the mountains of central Mexico, arriving like clockwork on November 1. However, this year the monarchs showed up late and in sobering numbers. Last year's migration was the all-time recorded low with 60 million butterflies arriving in Mexico, this year only 3 million have appeared, according to The New York Times.
Mexicans have celebrated the migration of the butterflies for years on the Day of the Dead, believing that the monarchs are the returning souls of those who have passed. Sadly enough, the monarchs are dying off before they even begin their arduous journey. Although pesticides are certainly a major factor, scientists attribute much of the decline to the disappearance of native vegetation across the U.S., reports The Times.
Much of the vegetation loss can be attributed to our farming practices. As prices of crops such as corn have grown, farmers have expanded their operations and are using pesticides like roundup. The combination of these practices not only wipes out habitat, but often makes surviving vegetation toxic to insects.
Some studies show that Iowa has lost up to 90 percent of its milkweed—a vital source of nectar for many species—greatly affecting a variety of insect populations, according to reports from The Times. Studies like these coupled with never-ending development and construction leave the butterflies and other insects nowhere to live.
Most of these issues are also plaguing the bee population, and in many cases are having a larger impact. “If the bees were to truly disappear, we would lose 80 percent of the plants,” Dr. Tallamy told The Times. “That is not an option. That’s a huge problem for mankind.”