Where Have All the Monarch Butterflies Gone ?

For the beloved monarch butterflies, these are dire times. 

In 1980s, as many as 170,000 monarchs would descend each fall and spring upon Natural Bridges State Beach in Santa Cruz, California, to spend the winter in a seaside eucalyptus grove.

This year, however, just 3,800 monarch's showed up in what has been a steady and precipitous drop-off in population.

"Across the country, we're looking at the lowest returning monarch population we've seen," said Chip Taylor, professor of entomology at the university of Kansas and director of Monarch Watch. "Its a bit curious as to the reason we're seeing such precipitous declines, but we do have theories."

Taylor told AOL News that a combination of factors is likely responsible for the swift decline in the number of monarchs gracing American skies.

First, Taylor said, is the degradation of the wintering grounds around Michoacan, Mexico, because of deforestation of areas where the butterflies typically congregate.

Second is the loss of habitat in the United States. Monarch caterpillars exclusively feed on milkweed, which grows wild in much of the country, but is often removed or killed off with pesticides when wild lands are adapted for other uses.

Third is the climate change. "California and much of West has gotten warmer in recent years," Taylor said, "drying up sources of water that the butterflies rely upon. In the East, we've had a few colder-than-usual summers. I tell people we have a goldilocks situation with the butterflies. They don't like it too warm and they don't like it too cold."

Another factor that seems to be stacked against the monarch is that the females of the species has dropped over the past few decades. Andy Davis, a researcher at the University of Georgia, conducted a study in which he discovered that while 54 percent of all monarch were female in the middle 1970s. only 43 percent are today.

While the ultimate prognosis for the monarch remain uncertain, Taylor, Davis and others concur that the loss of one of the continent's most iconic insects would be a tragedy. 

Source: AOL News.