Genetically Modified Crops Fueling Decline of Monarch Butterflies: Report

http://www.commondreams.org/headline/2014/06/05-5



New study links loss of milkweed habitat as a result of herbicide resistant crops to monarchs' falling numbers

Genetically Modified Crops Fueling Decline of Monarch Butterflies: Report
- Andrea Germanos, staff writer
Published on Thursday, June 5, 2014 by Common Dreams

The monarch butterflies' numbers have been plummeting in recent years, and a new study has pointed to the likely main culprit: loss of its summer habitat as a result of genetically modified crops.

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A report issued earlier this year from the World Wildlife Fund and Mexico’s National Commission for Protected Areas pointed to three main factors threatening the pollinators: deforestation and forest degradation in monarch reserves that serve as their winter habitat in Mexico, habitat loss due to land use changes and the loss of its larval food plant—milkweed—as a result of the widespread use of the herbicide glyphosate, and weather extremes.

The new study, however, puts the main cause of the crisis squarely on its summer habitat loss in the United States.

The researchers' projection model showed that disturbances in their breeding grounds affected the butterflies' number to a greater degree than disturbances to their wintering grounds. Those breeding grounds need to have milkweed, the only host plant for the monarch caterpillars.