Demand for crops such as soybeans and corn is such that more and more open grassland where plants like milkweed flourish is being plowed under and put into agricultural service. These crops, which are genetically-modified to be resistant to herbicides, are then sprayed with weed-killers that prevent milkweed from growing back, even in unplanted areas such as along roads or ditches. The result is that the Midwest, which is a critical monarch hatching ground, is increasingly devoid of the only plant monarch larvae can eat.Nationwide, organizations are working to increase the monarchs’ flagging numbers. At the University of Minnesota, a coalition of nonprofits and government agencies called Monarch Joint Venture is funding research and conservation efforts. At the University of Kansas, Monarch Watch has enlisted supporters to create nearly 7,450 so-called way stations, milkweed-rich backyards and other feeding and breeding spots along migration routes on the East and West Coasts and the Midwest.But it remains an uphill struggle. The number of monarchs that completed the largest and most arduous migration this fall, from the northern United States and Canada to a mountainside forest in Mexico, dropped precipitously, apparently to the lowest level yet recorded. In 2010 at the University of Northern Iowa, a summertime count in some 100 acres of prairie grasses and flowers turned up 176 monarchs; this year, there were 11.The decline has no single cause. Drought and bad weather have decimated the monarch during some recent migrations. Illegal logging of its winter home in Mexico has been a constant threat. Some studies conclude that pesticides and fungicides contribute not just to the monarchs’ woes, but to population declines among bees, other butterflies and pollinators in general.But the greatest threat to the butterfly, most experts agree, is its dwindling habitat in the Midwest and the Great Plains, the vast expanse over which monarchs fly, breed new generations and die during migrations every spring and autumn. Simply put, they say, the flyway’s milkweed may no longer be abundant enough to support the clouds of monarchs of years past.
The monarch has been under increasing pressure for awhile now - I wrote about a drop in their population back in March of 2010 - but it's gotten to the point that the monarch is now listed as a "near threatened" species by the International Union for the Conservation of Nature.
Efforts to replenish milkweed sources are underway, as the article notes, and even some major corporations are participating. But the big problem the monarchs face right now is awareness; or, more specifically, the lack of it in regards to the threat they face.
Dr. Taylor, of Monarch Watch, said he was convinced that the annual migration to Mexico can be revived; butterfly populations, he said, can fluctuate wildly from year to year as weather and habitat change. The insect’s troubles probably were as deep, or deeper, during the Dust Bowl of the 1930s, he said. But so far, he said, monarch backers are mostly preaching to the choir, “and the choir’s of limited size.”Northern Iowa’s Dr. Jackson said it would take a much larger — and speedier — effort to undo the impact of thousands of square miles of habitat loss.“Monarchs are just like other iconic species,” she said. “Once people stop being accustomed to seeing them, they stop caring and they forget. Support drops like a ratchet.”
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