The rampant planting of genetically modified seeds is threatening the survival of monarch butterflies, the orange and black speckled species common—and critical—to Midwest farmers, according to a new study published in the journal Insect Conservation and Diversity.
The exact cause for the monarch population declines is debated among scientists, but the latest research cites the destruction of milkweed—the plant where the butterfly lays her eggs—as the main cause for the rapidly declining populations. Between 1999 and 2009, milkweed on Iowa farms declined by 90 percent.
Monarchs are migratory pollinators, playing an important role in the propagation of a number of plants throughout the country.
Milkweed is a common target for Roundup, the glyphosate based pesticide manufactured by the biotech corporation Monsanto, and used to kill weeds that threaten its GM Roundup Ready corn and soybeans, which are genetically designed to be resistant to the chemical.
The number of genetically modified crops being grown in the U.S. are staggering: Just this year, almost 95 percent of soybeans and more than 70 percent of corn will be adulterated seeds by biotech giants like Monsanto. The more GM crops are planted, the more Roundup and other glyphosate pesticides are used. According to the EPA, since the Roundup Ready crops were introduced in 1993, use of the pesticide has increased at least ten-fold.
But, milkweed may be declining for other reasons, too. Some scientists have pointed to urban sprawl, logging and other environmentally destructive practices besides the increase in genetically modified crops. And, there are other scientists who maintain that butterfly populations are not facing as significant a loss as speculated in the latest study.
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