While the monarch butterfly population made a comeback this year, the past two decades have been a major struggle for the vanishing species, and GMO crops in the United States along the migration route are one of the main culprits threatening the survival of this species.
Genetically modified soy and corn crops, covering huge swathes of the U.S. midwest where monarch butterflies travel every year on route from Canada to Mexico, are to blame for declining food sources for caterpillars, Mexico’s La Jornada reported Thursday.
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Herbicide resistant crops, like Monsanto’s notorious “Roundup Ready” corn and soybeans, are highly correlated with the decline in milkweed, which monarch butterflies rely on to lay their eggs and as the main food source for caterpillars.
Over 90 percent of corn and soy grown in the United States is genetically engineered, according to the U.S. Department of Agriculture.
Scientific studies suggest that the monarch butterflies could be doomed as the long-term population decline continues.
Other threats to the butterfly population include other forms of habitat loss such as illegal logging, severe storms, and climate change, which makes a long migration journey even more difficult.
Environmental groups have petitioned to see the monarch butterfly added to the U.S. list of endangered species that requires special protection. The requests are still being reviewed.
Meanwhile, the U.S. Fish and Wildlife Service is working with other conservation groups to try to save monarch butterflies by planting milkweed in hopes of restoring essential habitat and food sources.
Most monarchs butterflies only live a few weeks.
WATCH: Herbicides Cause 90% Drop in Monarch Butterfly Population