In late December of 2014 scientists reported that more monarch butterflies appeared to have made the arduous journey from the U.S. and Canada to their warm winter nesting grounds in the oyamel fir trees of western Mexico’s Michoacán state,which raised hopes worldwide after the number of monarchs in Mexico dropped to record lows in 2013. Still,concerns are high as unusually cold temperatures could continue to threaten the delicate yet tenacious insects through May of this year.
Each fall,tens of millions of these whimsical creatures clump together in their ancestral breeding grounds,forming what appears to be “clouds” of butterflies as they form elaborate chandelier shapes in the trees. They came to Mexico two weeks later than normal last fall,arriving in mid-November instead of late October,when they usually come just in time for Day of the Dead celebrations.
“Cold weather is the biggest threat to the monarchs between now and March,when they take flight back north,” shared Gloria Talavera,director of the official Monarch Butterfly Biosphere Reserve,which is a UNESCO World Heritage Site. “They are seeking out canyons,seeking out more protected areas. We are seeing unusual things,all of them related to the climate.”
As we reported last spring,world leaders have vowed to protect the natural habitat of Mexico’s monarch butterflies after scientists have noted a sharp decline in the number of butterflies making the amazing 3,000-mile journey in recent years. The migration is an inherited trait,which means that not one butterfly survives to make the entire round trip. This makes it an ongoing mystery how the beautiful orange and black insects know where to go. What we do know is factors such as logging in Mexico and the decline of milkweed in the U.S. due to the use of pesticides are playing a huge role in their decline.
“The butterflies are at their most vulnerable moment because of pesticide use in the United States,climate change along their migratory route and degradation of the forests where they winter,” shared respected writer and environmentalist Homero Aridjis on Fox News.
Observers count monarchs in Mexico by estimating how many acres they cover,not individually,and 2013 saw the lowest levels since recordkeeping began 20 years earlier. At their peak,the insects covered more than 44 acres (18 hectares) but last year they only covered 1.65 acres (.67 hectares). Fortunately,Fox News reports that the area occupied by monarchs following their migration this year has grown by 69 percent compared to last season,reaching 2.8 acres (1.13 hectares) although it’s still among the lowest numbers in recent decades.
“The monarchs face particular risks because of the loss of feeding grounds across the U.S. corn belt,where widespread use of herbicides is wiping out the milkweed species that are the staple food for butterfly larvae,” shared Omar Vidal,president of WWF Mexico,in a recent interview with Fox News. “Conservation groups in the United States have asked authorities to list the monarch butterfly as a species in risk of extinction.”
Click here to read more about the negative effects chemical pesticides,herbicides and genetically modified organisms can have on insects and what Mexico is doing to protect its natural resources.